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Default What size wiring for Central A/C compressor?

I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.
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Default What size wiring for Central A/C compressor?

On Mar 3, 8:22*pm, Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


normally a new install like a replacement AC will get all new wring
and service disvconnect. a new 8 gauge copper line with new disconnect
by the compressor will see less voltage drop, a good thing.

but new compressors will likely be more efficent and run with less
current.

if everything is open then this is the best time to upgrade, and if
breaker space is available run a couple 20 amp lines to work boxes for
future use if needed. I did that once and a few years later was glad I
did when we decided to install a new kitchen
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Default What size wiring for Central A/C compressor?

On 3/3/2013 7:22 PM, Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


In The U.S., standard gauge copper wire for a 20 amp circuit is 12 gauge
and 10 gauge for a 30 amp circuit. Below is a link to a chart
for standard current ratings for home wiring. There are all sorts
of different ratings for different insulation types, wire in free air,
in conduit or buried but the chart shows what any electrician would
go by if wiring a home. Aluminum wiring is usually one gauge size larger
for the same current carrying capacity as copper. ^_^

http://www.cerrowire.com/ampacity-charts

TDD

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Default What size wiring for Central A/C compressor?

On Mar 3, 8:55*pm, wrote:
On Sun, 3 Mar 2013 17:22:54 -0800 (PST), Mikepier

wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


OK hold on to your hat.

That label says max fuse or breaker 40a ... that is what you have

It also says minimum circuit ampacity 24.4a so the wire can be 12 ga.

You are larger than you have to be with 10ga.

That is what happens in article 440. They know you need a big breaker
to get the compressor going but the actually running current is much
lower. If you look at 310.15 you will see #12 is actually rated at
25a,.
The common axiom that 14ga = 15a, 12ga = 20a comes from 240(4)(D)
where they build the 80% safety factor in. (it is actually the max
breaker size) It does not apply on dedicated motor circuits
Homeowners will keep plugging things in until the breaker trips, then
unplug the clock.

That label has it built in *already by the engineer. You will see that
compressor actually runs more like 16-18a on a hot day.


I understand what the article is saying, but at the very least,
shouldn't the 10 guage wire be on a 30A breaker and not 40A?

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Default What size wiring for Central A/C compressor?

On 3/3/13 8:46 PM, Mikepier wrote:

I understand what the article is saying, but at the very least,
shouldn't the 10 guage wire be on a 30A breaker and not 40A?

The rules are different for motors than on other things for what
it's worth. Wire is supposed to be sized at 125% of the full load
amperage shown on the appropriate chart. Overcurrent protection can be
175% of the value shown in the chart. One can go to the next larger
size if the 175% calculation puts one in between standard fuse or
breaker sizes.
This might not apply directly to air conditioners but I think the
code writer's reasoning is the same.


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Default What size wiring for Central A/C compressor?

Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.

Greg
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Default What size wiring for Central A/C compressor?

On 3/3/2013 9:46 PM, gregz wrote:
Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.

Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o

TDD
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Default What size wiring for Central A/C compressor?

On Mar 3, 11:16*pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:





Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o

TDD- Hide quoted text -

- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.
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Default What size wiring for Central A/C compressor?

On Mar 3, 8:57*pm, bob haller wrote:
On Mar 3, 8:22*pm, Mikepier wrote:

I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


normally a new install like a replacement AC will get all new wring
and service disvconnect.


Not around these parts. Unless the wiring is too small,
deteriorated, etc. If not, then typically just the disconnect
box on the exterior is changed.




a new 8 gauge copper line with new disconnect
by the compressor will see less voltage drop, a good thing.

but new compressors will likely be more efficent and run with less
current.

if everything is open then this is the best time to upgrade, and if
breaker space is available run a couple 20 amp lines to work boxes for
future use if needed. I did that once and a few years later was glad I
did when we decided to install a new kitchen


Why can't you just add those later, when and if needed?
It's easier to just connect new wires to new breakers rather
than install boxes, deal with splices, etc.
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Default What size wiring for Central A/C compressor?

On 3/4/2013 6:13 AM, wrote:
On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:





Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o

TDD- Hide quoted text -

- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker. A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable. An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC. This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring. I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly. There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^

TDD


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Default What size wiring for Central A/C compressor?

On Mar 4, 7:50*am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:





On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.




A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.





An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.



This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.




I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.






There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^

TDD- Hide quoted text -

- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.
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Default What size wiring for Central A/C compressor?

On 3/4/2013 7:56 AM, wrote:
On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:





On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.




A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.





An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.



This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.




I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.






There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^

TDD- Hide quoted text -

- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area. I don't argue with inspectors either because
they can call people who carry guns and handcuffs. ^_^

TDD
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Default What size wiring for Central A/C compressor?

On Mar 4, 10:50*am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:





On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. *As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. *That translates
into 10 guage wire being fine. *Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. * Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. *But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. *Itfully *meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. And it would pass inspection here,
in NJ. Or do your inspectors just make stuff up as they
go along?



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Default What size wiring for Central A/C compressor?

On 3/4/2013 10:27 AM, wrote:
On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:





On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. And it would pass inspection here,
in NJ. Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.
All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.
Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^

TDD

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Default What size wiring for Central A/C compressor?

On Monday, March 4, 2013 11:50:42 AM UTC-5, The Daring Dufas wrote:
Everywhere I've worked followed the NEC even on U.S. installations

overseas where The Army Corps of Engineers took care of inspections.


Except where they conflict with the DIN. Usually you can go with what is most stringent, but sometimes the NEC and DIN conflict and can't both be met.


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Default What size wiring for Central A/C compressor?

On Mar 4, 11:50*am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:





On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable..


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. *As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. *That translates
into 10 guage wire being fine. *Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. * Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. *But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. *Itfully *meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. *And it would pass inspection here,
in NJ. *Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.




All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. And gfretw has weighed in on
the issue. I believe he's an electrician. And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.




Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^

TDD- Hide quoted text -

- Show quoted text -


We follow the NEC here. So show us where the NEC says
we're wrong..... And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.
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Default What size wiring for Central A/C compressor?

On Mon, 4 Mar 2013 03:46:05 +0000 (UTC), gregz
wrote:

Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.

If you figure a SEER of 12, 3.5T (42,000BTU/HR) is 3.5kW or 14.5A. To
get to 6.5A you'd have to have a SEER of 27! Something's not adding
up here.
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Default What size wiring for Central A/C compressor?


"The Daring Dufas" wrote in message
...

I'm not going to argue with you over it except to tell you it would not
pass inspection in my area. I don't argue with inspectors either because
they can call people who carry guns and handcuffs. ^_^

TDD


Some areas fo the counrty do not exectally follow the NEC. Unless you have
a very good reason and can show the inspector where he is mistaken, it is
best to just do as they say. If you ever get on their bad side, they will
really look over your work and try to find a reason to make you redo
something.

It doesn't mater about the gun and cuffs, but they can have the power cut
off or not turned on in the first place.



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Default What size wiring for Central A/C compressor?

On 3/4/2013 11:15 AM, TimR wrote:
On Monday, March 4, 2013 11:50:42 AM UTC-5, The Daring Dufas wrote:
Everywhere I've worked followed the NEC even on U.S. installations

overseas where The Army Corps of Engineers took care of inspections.


Except where they conflict with the DIN. Usually you can go with what is most stringent, but sometimes the NEC and DIN conflict and can't both be met.


My experience is with American protectorates where the facilities are
the same as back home. ^_^

TDD
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Default What size wiring for Central A/C compressor?

On 3/4/2013 11:47 AM, wrote:
On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:





On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. And it would pass inspection here,
in NJ. Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.




All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. And gfretw has weighed in on
the issue. I believe he's an electrician. And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.




Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^

TDD- Hide quoted text -

- Show quoted text -


We follow the NEC here. So show us where the NEC says
we're wrong..... And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?

TDD


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Default What size wiring for Central A/C compressor?

On 3/4/2013 12:09 PM, Ralph Mowery wrote:
"The Daring Dufas" wrote in message
...

I'm not going to argue with you over it except to tell you it would not
pass inspection in my area. I don't argue with inspectors either because
they can call people who carry guns and handcuffs. ^_^

TDD


Some areas fo the counrty do not exectally follow the NEC. Unless you have
a very good reason and can show the inspector where he is mistaken, it is
best to just do as they say. If you ever get on their bad side, they will
really look over your work and try to find a reason to make you redo
something.

It doesn't mater about the gun and cuffs, but they can have the power cut
off or not turned on in the first place.


I get along with the inspectors and since I know them and they know the
quality of my work, they don't usually dig to deeply into it unless I
insist in order to satisfy a customer who may have doubts. That is
something they understand since they themselves worked in the field. In
some places they actually have to use a stamp with their name and number
for the department which can be seen inside breaker panel doors. ^_^

TDD
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Default What size wiring for Central A/C compressor?

On 3/4/2013 12:50 PM, The Daring Dufas wrote:
....

base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?


....

Far more likely they apply the correct section of Code for the purpose
at hand.

It would be far better to reference the specific Code in question or
even the controlling jurisdiction which would likely lead to being able
to find the relevant Codes in play. I strongly suspect if that were
done it would be found that the installation under discussion is
compliant there as well.

--
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Default What size wiring for Central A/C compressor?

On 3/4/2013 2:15 PM, wrote:
On Mon, 04 Mar 2013 12:50:54 -0600, The Daring Dufas
wrote:


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?

TDD


I have been a certified, state licensed electrical inspector for about
20 years.

Florida and we follow the NEC state wide, unaltered, except for
requiring bonding of steel studs.

I said before, this is a common question on the inspector tests and if
you say 8ga on a 40a breaker for a motor circuit like this, you got
that one wrong.
Maybe your inspectors are not certified and it is just the mayor's
nephew who learned his trade from the Time Life electrical wiring for
dummies book.


That's what they want around here with a disconnect at the condensing
unit. I've always gone by the breaker size required by the label on the
unit and sized the wiring for the breaker and that's what the inspectors
want. If you were the inspector at the site, I would do what you
demanded. It can't be simpler than that. Of course, different insulation
types handle different currents. I don't argue with the inspector and do
what their department requires. The inspectors around here would reject
a 40 amp breaker on #10 copper 60°C NM/UF cable. Higher temp rated wire
insulation would be different. NEC Table 310-16. I would put a 40amp
breaker on #10 copper if it has 90°C rated THHN/THWN/XHHW insulation. O_o

TDD
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Default What size wiring for Central A/C compressor?

On Mar 4, 3:15*pm, wrote:
On Mon, 04 Mar 2013 12:50:54 -0600, The Daring Dufas

wrote:
How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?


TDD


I have been a certified, state licensed electrical inspector for about
20 years.

Florida and we follow the NEC state wide, unaltered, except for
requiring bonding of steel studs.

I said before, this is a common question on the inspector tests and if
you say 8ga on a 40a breaker for a motor circuit like this, you got
that one wrong.
Maybe your inspectors are not certified and it is just the mayor's
nephew who learned his trade from the Time Life electrical wiring for
dummies book.


It's also possible that he's basing his experience on what's required
by what he's used and had passed. Of course if you use
8 gauge where a minimum of 12 gauge or 10 gauge is required, it
passes because it meets code. And the inspector isn't likely to
say,
BTW did you know that 12 was sufficient? So, he goes on
thinking that 8 gauge is what is required for it to pass.

Obviously there hasn't been any discussion with an inspector
about the issue, otherwise he'd be able to give us the code
section that the position is based on. He refuses to recognize
that the code treats breaker requirements for general purpose
branch circuits differently than it does for motors, AC eqpt, etc.

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Default What size wiring for Central A/C compressor?

On Mar 4, 1:50*pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 11:47 AM, wrote:





On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:


On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements..


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. *As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. *That translates
into 10 guage wire being fine. *Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. * Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. *But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. *Itfully *meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. *And it would pass inspection here,
in NJ. *Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.


All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. *And gfretw has weighed in on
the issue. *I believe he's an electrician. *And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.


Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^


TDD- Hide quoted text -


- Show quoted text -


We follow the NEC here. *So show us where the NEC says
we're wrong..... * And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. * This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. *Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?

TDD- Hide quoted text -

- Show quoted text -


When you can give us the section of the NEC where you can
conclude that there is something wrong with Mikepier's
installation, under ANY interpretation, then we can discuss differing
interpretations. If an inspector is going to fail it, then he should
be
able to tell you that per NEC section X.Y, it's not allowed.

This isn't the first time this issue has come up. And the result is
usually the same. You have some people thinking that the same
rules for lights and receptacles under the NEC also apply to
motors and AC equipment. They don't. I would hope that
someone who installs that eqpt would understand the distinction.





  #26   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 4,463
Default What size wiring for Central A/C compressor?

On 3/4/2013 3:27 PM, wrote:
On Mar 4, 1:50 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 11:47 AM, wrote:





On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:


On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. And it would pass inspection here,
in NJ. Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.


All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. And gfretw has weighed in on
the issue. I believe he's an electrician. And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.


Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^


TDD- Hide quoted text -


- Show quoted text -


We follow the NEC here. So show us where the NEC says
we're wrong..... And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?

TDD- Hide quoted text -

- Show quoted text -


When you can give us the section of the NEC where you can
conclude that there is something wrong with Mikepier's
installation, under ANY interpretation, then we can discuss differing
interpretations. If an inspector is going to fail it, then he should
be
able to tell you that per NEC section X.Y, it's not allowed.

This isn't the first time this issue has come up. And the result is
usually the same. You have some people thinking that the same
rules for lights and receptacles under the NEC also apply to
motors and AC equipment. They don't. I would hope that
someone who installs that eqpt would understand the distinction.


If you'll look at NEC Table 310-16 you will see the amp rating for wire
size. It changes depending on the insulation on the wire. Every 40 amp
circuit I've ever installed in a home using 60°C NM/UF cable has been #8
copper. If I install a 40 amp circuit in conduit using 90°C THHN/THWN
insulated wire I'll use #10 copper. I don't usually run conduit in a
home. The last 4 ton AC condensing unit I installed used #14 THHN/THWN
copper in conduit. It was a 3ø unit that called for a 15 amp breaker. I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o

TDD

  #27   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,399
Default What size wiring for Central A/C compressor?

On Mar 4, 5:55*pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 3:27 PM, wrote:





On Mar 4, 1:50 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 11:47 AM, wrote:


On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:


On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. *As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. *That translates
into 10 guage wire being fine. *Actually, 12 would also meet it..
It further states that a 40 amp breaker is the max allowed, which
is what he has. * Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. *But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring.. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. *Itfully *meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. *And it would pass inspection here,
in NJ. *Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.


All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. *And gfretw has weighed in on
the issue. *I believe he's an electrician. *And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.


Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^


TDD- Hide quoted text -


- Show quoted text -


We follow the NEC here. *So show us where the NEC says
we're wrong..... * And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. * This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. *Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?


TDD- Hide quoted text -


- Show quoted text -


When you can give us the section of the NEC where you can
conclude that there is something wrong with Mikepier's
installation, *under ANY interpretation, then we can discuss differing
interpretations. *If an inspector is going to fail it, then he should
be
able to tell you that per NEC section X.Y, it's not allowed.


This isn't the first time this issue has come up. *And the result is
usually the same. *You have some people thinking that the same
rules for lights and receptacles under the NEC also apply to
motors and AC equipment. * They don't. *I would hope that
someone who installs that eqpt would understand the distinction.


If you'll look at NEC Table 310-16 you will see the amp rating for wire
size. It changes depending on the insulation on the wire.

Every 40 amp
circuit I've ever installed in a home using 60°C NM/UF cable has been #8
copper. If I install a 40 amp circuit in conduit using 90°C THHN/THWN
insulated wire I'll use #10 copper.


And if you look at that table, it shows that 12 gauge is OK for
up to 25 amps. The nameplate on the AC eqpt Mike has says
the minimum circuit ampacity is 24.4 amps. Therefore, 12 gauge
meets the minimum requirement and is permitted.

The problem comes when you then try to tie the breaker to be
installed for that AC eqpt with the wire size and treat it like it
was a water heater, or a receptacle circuit. It is not. The eqpt
manufacturer's rating governs and it says that a breaker of
40A max is permitted.



I don't usually run conduit in a
home. The last 4 ton AC condensing unit I installed used #14 THHN/THWN
copper in conduit. It was a 3ø unit that called for a 15 amp breaker.


15 amp breaker for a 4 ton AC? That ain't right.



I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o

TDD- Hide quoted text -

- Show quoted text -


It's not an issue of arguing with the inspectors. It's what the
NEC says disagrees with what you say. And if an inspector fails
something, he should be willing to tell you what part of the code
it failed and why, without getting into an argument. Any inspector
should know that motors are treated differently than resistive
loads.

Just do some googling. This whole issue has come up many
times. Some homeowner or inspector raises the issue of the
breaker for an AC being larger than would normally be permitted
for a light circuit, etc. that uses a given wire gauge. Or some home
inspector flags it. Then a lot of discussion follows and the folks
most knowledgable about the actual issues and code say
it's perfectly normal. In this case, you have gfretw, an actual
electrical inspector, telling you how it works and that what Mike
has is code compliant.
  #28   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 1,199
Default What size wiring for Central A/C compressor?

On Mar 4, 5:55*pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 3:27 PM, wrote:





On Mar 4, 1:50 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 11:47 AM, wrote:


On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:


On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. *So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the *existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide *open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. *As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. *As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. *That translates
into 10 guage wire being fine. *Actually, 12 would also meet it..
It further states that a 40 amp breaker is the max allowed, which
is what he has. * Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. *But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring.. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. *Itfully *meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. *And it would pass inspection here,
in NJ. *Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.


All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. *And gfretw has weighed in on
the issue. *I believe he's an electrician. *And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.


Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^


TDD- Hide quoted text -


- Show quoted text -


We follow the NEC here. *So show us where the NEC says
we're wrong..... * And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. * This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. *Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?


TDD- Hide quoted text -


- Show quoted text -


When you can give us the section of the NEC where you can
conclude that there is something wrong with Mikepier's
installation, *under ANY interpretation, then we can discuss differing
interpretations. *If an inspector is going to fail it, then he should
be
able to tell you that per NEC section X.Y, it's not allowed.


This isn't the first time this issue has come up. *And the result is
usually the same. *You have some people thinking that the same
rules for lights and receptacles under the NEC also apply to
motors and AC equipment. * They don't. *I would hope that
someone who installs that eqpt would understand the distinction.


If you'll look at NEC Table 310-16 you will see the amp rating for wire
size. It changes depending on the insulation on the wire. Every 40 amp
circuit I've ever installed in a home using 60°C NM/UF cable has been #8
copper. If I install a 40 amp circuit in conduit using 90°C THHN/THWN
insulated wire I'll use #10 copper. I don't usually run conduit in a
home. The last 4 ton AC condensing unit I installed used #14 THHN/THWN
copper in conduit. It was a 3ø unit that called for a 15 amp breaker. I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o

TDD- Hide quoted text -

- Show quoted text -


This is interesting stuff guys. I never knew there were a different
set of codes for motors and A/C's.
I'll leave the existing wiring for now. What I'll do is run a drag
line in the ceiling joists so if i ever had to run another line, I can
do it easily by pulling the new wire attached to the drag line.

I have another question regarding central Vac systems wiring
requirements. Please see upcoming seperate post.
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Default What size wiring for Central A/C compressor?

wrote:
On Mon, 4 Mar 2013 03:46:05 +0000 (UTC), gregz
wrote:

Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.

If you figure a SEER of 12, 3.5T (42,000BTU/HR) is 3.5kW or 14.5A. To
get to 6.5A you'd have to have a SEER of 27! Something's not adding
up here.


Right.

It's pretty cold outside ! A couple of things. My memory is bad. The unit
is in fact 2.5 tons. The installer quoted price for 3 ton unit !

Gsc130301a goodman.
13.7 minimum amp
Max fuse amps 20
Compressor 9.7 amp
1.5 hp fan.

The reading have been stable last 2-3 summers. 6.5 amp draw.
Could low r22 cause reduced reading ?

Im happy with the performance, low bills. I even drop the temp down to 68
degrees in summer nights.

Greg
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Default What size wiring for Central A/C compressor?

On 3/4/2013 6:12 PM, wrote:
On Mar 4, 5:55 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 3:27 PM, wrote:





On Mar 4, 1:50 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 11:47 AM, wrote:


On Mar 4, 11:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 10:27 AM, wrote:


On Mar 4, 10:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 7:56 AM, wrote:


On Mar 4, 7:50 am, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/4/2013 6:13 AM, wrote:


On Mar 3, 11:16 pm, The Daring Dufas the-daring-du...@stinky-
finger.net wrote:
On 3/3/2013 9:46 PM, gregz wrote:


Mikepier wrote:
I'm running new electric in a friends basement and so far uncovered a
lot of bad wiring jobs, buried splice boxes, you name it. So now I
noticed that the central A/C compressor is wired with 10 guage wire.
I'm pretty sure its suppose to be 8 guage. And also the existing 10
guage wire is hooked up to a 40 A breaker, which of course is not
right, its suppose to be a 30A breaker.
So since everything is wide open now, I was wondering should I run
new 8 guage wire to the A/C? The unit is a Lennox, I beleive a 3 ton
unit, and the plate says "Min circuit ampacity 24.4 amps" and it also
says " Max fuse or ckt bkr 40A".
Even if the unit has been running fine all these years, I'm wondering
what happens down the road if it needs to be replaced with a new unit
that needs more amperage. the existing 10 guage wire will not be
sufficient I'm thinking.


I had a 3.5 ton installed. They used 10 gauge and 30 amp breaker. After
reading data plate and measuring operating current I switched to 20 amp
breaker.
It's only drawing 6.5 Amps and no problems. Never hurts to use thicker
wire.


Greg


The circuit breaker is meant to protect the wiring not necessarily the
equipment which will normally have its own secondary protective devices.
The 20 amp breaker won't harm anything but if there is a surge current
greater than 20 amps from the AC unit starting on a hot day, you may get
nuisance tripping of the breaker. O_o


TDD- Hide quoted text -


- Show quoted text -


A 20 amp breaker is less than the rated 24 amp min
circuit capacity on the eqpt label. As others have stated, the
existing 12 gauge wiring and 40 amp breaker are
correct, meet code and no change is required.


Not around here. Every electrical inspector I know would reject a 12
gauge wired circuit with a 40 amp circuit breaker.


Then they are not following the NEC and either they don't know
what they are doing or that particualr AHJ has unusual requirements.


A 40 amp circuit
uses #8 copper NM/UF 60°C cable or #8 aluminum SE/USE 75°C cable.


You're trying to apply the NEC rules for general purpose branch
circuits to motor eqpt that is on a dedicated circuit with
it's own over-current protection. As the Mike stated, the eqpt
label says the minimum circuit ampacity is 24 Amps. That translates
into 10 guage wire being fine. Actually, 12 would also meet it.
It further states that a 40 amp breaker is the max allowed, which
is what he has. Presumably any competent electrical inspector
would read the eqpt label and follow it.


An
electrical inspector may require #6 aluminum be used depending on the
jurisdiction's requirements which may be stricter than The NEC.


Theoretically any AHJ could make up anything they want. But #6
for this 3 ton AC is nuts.


This
applies to "homes" not necessarily industry which will normally use
different wiring methods and higher temperature insulated wiring. I've
wired homes, businesses and industry for a living so I know a little
about electrical wiring.


Then you should know that what Mike has is perfectly fine.
It exceeds the eqpt label, which is what governs here and it
meets NEC.


I've also worked in commercial sales of
electrical products. The circuit breaker is meant to protect the wiring
and should always be sized accordingly.


You're ignoring the fact that the eqpt has it's own over-current
protection.


There are places that have no
electrical inspection department and I suppose you can do whatever you
want. I've worked in those areas too and seen extremely dangerous wiring
that was quite scary. ^_^


TDD- Hide quoted text -


- Show quoted text -


What Mike has is not dangerous. Itfully meets or exceeds NEC in
every regard.


I'm not going to argue with you over it except to tell you it would not
pass inspection in my area.


Then maybe you can tell us what rules the inspectors
are following and where your area is, because it's entirely
consistent with NEC. And it would pass inspection here,
in NJ. Or do your inspectors just make stuff up as they
go along?


Everywhere I've worked followed the NEC even on U.S. installations
overseas where The Army Corps of Engineers took care of inspections.


Then you should be able to cite for us the section of NEC
that says the installation that Mikepier has is in violation.
Reference please.


All I know is from my own experience working on various jobs over
four decades. Perhaps you have much more experience in the field of
electrical work than I do but I can only refer to my own experience.


I'm an electrical engineer. And gfretw has weighed in on
the issue. I believe he's an electrician. And he said the
same things I did, in particular that what Mike has is code
compliant and does not need to be changed.


Perhaps you are an experienced electrician in your city/state and know
how things are done in your kingdom but from your post, it appears you
follow different standards. I must contact my relatives in New Jersey
and implore them to run, run like the wind! ^_^


TDD- Hide quoted text -


- Show quoted text -


We follow the NEC here. So show us where the NEC says
we're wrong..... And until them, stop spreading FUD.
There is absolutely nothing unsafe, dangerous or in violation of NEC
in
what Mike has. This is a common confusion. Your mistake
is applying the rules for branch circuits for lights, receptacles, etc
to HVAC eqpt. Different rules apply for obvious reasons and if you'd
just take the time to read the NEC, you'll see that.


How often do you deal with electrical and mechanical inspection
services? I've done electrical and HVAC work for a living and I
base my assertions on practical experience where I've worked. It
may be different where you did your electrical and HVAC work for
a living. Perhaps the authorities interpret the NEC differently
where you have done your professional electrical and HVAC work?


TDD- Hide quoted text -


- Show quoted text -


When you can give us the section of the NEC where you can
conclude that there is something wrong with Mikepier's
installation, under ANY interpretation, then we can discuss differing
interpretations. If an inspector is going to fail it, then he should
be
able to tell you that per NEC section X.Y, it's not allowed.


This isn't the first time this issue has come up. And the result is
usually the same. You have some people thinking that the same
rules for lights and receptacles under the NEC also apply to
motors and AC equipment. They don't. I would hope that
someone who installs that eqpt would understand the distinction.


If you'll look at NEC Table 310-16 you will see the amp rating for wire
size. It changes depending on the insulation on the wire.

Every 40 amp
circuit I've ever installed in a home using 60°C NM/UF cable has been #8
copper. If I install a 40 amp circuit in conduit using 90°C THHN/THWN
insulated wire I'll use #10 copper.


And if you look at that table, it shows that 12 gauge is OK for
up to 25 amps. The nameplate on the AC eqpt Mike has says
the minimum circuit ampacity is 24.4 amps. Therefore, 12 gauge
meets the minimum requirement and is permitted.


Did you look at the notes from the table? They are at the bottom of the
table and will show what I use and what the inspectors go by. You will
see a little note reference next to the 25 amp figure. ^_^

TDD


The problem comes when you then try to tie the breaker to be
installed for that AC eqpt with the wire size and treat it like it
was a water heater, or a receptacle circuit. It is not. The eqpt
manufacturer's rating governs and it says that a breaker of
40A max is permitted.



I don't usually run conduit in a
home. The last 4 ton AC condensing unit I installed used #14 THHN/THWN
copper in conduit. It was a 3ø unit that called for a 15 amp breaker.


15 amp breaker for a 4 ton AC? That ain't right.


It is a 240 volt three phase unit and 15 amps 3ø power is what it calls
for. It has run without a problem for 10 years in three different
locations. I installed it at a pizza place which has moved twice after
I installed at their first location. I also use test equipment to check
the current draw and phase rotation on all three phase equipment. ^_^

TDD



I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o

TDD- Hide quoted text -

- Show quoted text -


It's not an issue of arguing with the inspectors. It's what the
NEC says disagrees with what you say. And if an inspector fails
something, he should be willing to tell you what part of the code
it failed and why, without getting into an argument. Any inspector
should know that motors are treated differently than resistive
loads.

Just do some googling. This whole issue has come up many
times. Some homeowner or inspector raises the issue of the
breaker for an AC being larger than would normally be permitted
for a light circuit, etc. that uses a given wire gauge. Or some home
inspector flags it. Then a lot of discussion follows and the folks
most knowledgable about the actual issues and code say
it's perfectly normal. In this case, you have gfretw, an actual
electrical inspector, telling you how it works and that what Mike
has is code compliant.


If gfretw was the inspector in charge I would do what he said but I have
to go by what the inspectors here and now require. I also go by
the manufacturers requirements unless they clash with the inspector
who has final say. The city here actually has stricter guidelines in
some areas than the NEC. Here, they want the circuit and wire gauge
to match no matter what the load is with the only difference being that
HACR rated breakers be used on AC and refrigeration units. Understand
that the temperature rating of the insulation also determines the amp
carrying specification of the wiring for both copper and aluminum. ^_^

TDD




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On 3/4/2013 8:46 PM, wrote:
On Mon, 04 Mar 2013 16:55:43 -0600, The Daring Dufas
wrote:

If you'll look at NEC Table 310-16 you will see the amp rating for wire
size. It changes depending on the insulation on the wire. Every 40 amp
circuit I've ever installed in a home using 60°C NM/UF cable has been #8
copper. If I install a 40 amp circuit in conduit using 90°C THHN/THWN
insulated wire I'll use #10 copper. I don't usually run conduit in a
home. The last 4 ton AC condensing unit I installed used #14 THHN/THWN
copper in conduit. It was a 3ø unit that called for a 15 amp breaker. I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o


You have to look at the whole code, in context, you can't just cherry
pick one article and believe that is the way it works in every
situation.
When you are looking at an AC unit you start in 440 if you are sizing
the breaker, not using the label.

440.22 Application and Selection.
(A) Rating or Setting for Individual Motor-Compressor. The
motor-compressor branch-circuit short-circuit and ground-fault
protective device shall be capable of carrying the starting current of
the motor. A protective device having a rating or setting not
exceeding 175 percent of the motor-compressor rated-load current or
branch-circuit selection current, whichever is greater, shall be
permitted, provided that, where the protection specified is not
sufficient for the starting current of the motor, the rating or
setting shall be permitted to be increased but shall not exceed 225
percent of the motor rated-load current or branch-circuit selection
current, whichever is greater.

12 ga wire has an ampacity of 25a in the 60c column so you can start
with a 45a breaker and you might end up with a 60 if you use the round
up rule at 225%.
The label is actually rounding down to get to 40a.

The label is very unambiguous. It tells you can use 12ga wire and a
40a breaker. If an inspector is confused about that, he is
incompetent. I am not saying there are not incompetent inspectors out
there but at a certain point they need to be educated. That probably
does not happen on an active job but you can send a letter to the
state licensing authority asking for a ruling. Fix it for everyone,
not just that job.

What is your jurisdiction? I may actually know someone there.


It's Birmingham in Jefferson County Alabamastan. I noted the 25 amp
rating in the 60°C column too but I also read the notes at the bottom
of the chart and those jive with what has always been told to me. The
city code does differ a bit from NEC and that's what I've been told by
the inspectors I've dealt with. Now in your experience are you also
considering LRA of the compressor? Is that part of the 225% overload? O_o

TDD
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Default What size wiring for Central A/C compressor?

On 3/5/2013 12:12 AM, wrote:
On Mon, 04 Mar 2013 22:21:55 -0600, The Daring Dufas
wrote:

On 3/4/2013 10:06 PM,
wrote:
On Mon, 04 Mar 2013 20:36:50 -0600, The Daring Dufas
wrote:

And if you look at that table, it shows that 12 gauge is OK for
up to 25 amps. The nameplate on the AC eqpt Mike has says
the minimum circuit ampacity is 24.4 amps. Therefore, 12 gauge
meets the minimum requirement and is permitted.

Did you look at the notes from the table? They are at the bottom of the
table and will show what I use and what the inspectors go by. You will
see a little note reference next to the 25 amp figure. ^_^


Absolutely. That note takes you to 240.4(D) which references 240.4(G)

G) Over current Protection for Specific Conductor Applications. Over
current protection for the specific conductors shall be permitted to
be provided as referenced in Table 240.4(G).

which references 440 part III & IV and 430 part III, IV, V, VI & VII
where we get this permission for larger OC devices and the ability to
use 310.16 at the listed rating.

Like I said, you need to read the whole code, not just the first thing
you see.


I'll defer to you on it then but I'll continue to install what I know
will pass inspection not what I think I can get away with. ^_^

TDD


Whatever you need to do. You are just oversizing wire but as long as
you keep getting the bid, rock on.

You probably should have the conversation tho. I am curious how your
inspectors can ignore that label.


I remember one who would not pass a job unless the HACR sticker was on
the breaker for the AC. It didn't matter what the paperwork from the
manufacturer stated. O_o

TDD
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Default What size wiring for Central A/C compressor?

On 3/4/2013 8:46 PM, wrote:
On Mon, 04 Mar 2013 16:55:43 -0600, The Daring Dufas
wrote:

....

... I
have to install what I know the inspector will pass and the inspectors
do look at the temperature rating of the wire and check if the circuit
breaker is HACR rated if it's hooked to an AC condensing unit. I don't
argue with the inspectors, you can if you wish. O_o


You have to look at the whole code, in context, you can't just cherry
pick one article and believe that is the way it works in every
situation.
When you are looking at an AC unit you start in 440 if you are sizing
the breaker, not using the label.

440.22 Application and Selection.
(A) Rating or Setting for Individual Motor-Compressor. The
motor-compressor branch-circuit short-circuit and ground-fault
...[Code detail elided for brevity]...

12 ga wire has an ampacity of 25a in the 60c column so you can start
with a 45a breaker and you might end up with a 60 if you use the round
up rule at 225%.
The label is actually rounding down to get to 40a.

The label is very unambiguous. It tells you can use 12ga wire and a
40a breaker. If an inspector is confused about that, he is
incompetent. I am not saying there are not incompetent inspectors out
there but at a certain point they need to be educated. That probably
does not happen on an active job but you can send a letter to the
state licensing authority asking for a ruling. Fix it for everyone,
not just that job.


+about5

If the inspectors in this area are this bad, they're costing a lot of
money over time for no reason (other than perhaps kickbacks from the
local distributors???)

When first in TN years ago there was an incompetent so widely known that
it was a standing joke. The locals put up w/ it and just bought
innumerable pints of Old Turkey (from which you can imagine the joke).

I finally got fed up enough and being new to the area was willing to be
the one who pulled his plug by documenting it and making the complaint.
In the end, was _much_ "more better" all around...

--


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Default What size wiring for Central A/C compressor?

The Daring Dufas wrote:

If gfretw was the inspector in charge I would do what he said but I
have to go by what the inspectors here and now require. I also go by
the manufacturers requirements unless they clash with the inspector
who has final say. The city here actually has stricter guidelines in
some areas than the NEC. Here, they want the circuit and wire gauge
to match no matter what the load is with the only difference being
that HACR rated breakers be used on AC and refrigeration units.
Understand that the temperature rating of the insulation also
determines the amp carrying specification of the wiring for both
copper and aluminum. ^_^


I replaced my 3-ton a/c unit after its 12-year old predecessor croaked as a
result of Hurricane Yikes*. The chap who replaced it said I could also swap
out the 40-amp breaker with a 30-amp one inasmuch as more modern units, mine
included, were more efficient and drew less power. Makes sense since the
original a/c unit was a builder model from the 1960's. The compressor unit,
no doubt, had been replaced, maybe more than once, before I bought the
house. But nobody every fiddled with changing the circuit breaker.

----------------
* The fellow who did the work is a Guatamalan off-the-books a/c technician.
Evidently he is part of a co-national underground network of repair people
in that he knew a guy who obtains and reconditions a/c units, some from
insurance companies after house fires. Anyway, the unit he chose was a
two-year old Trane, and the unit has been working swell for the past four
years. The whole business, compressor unit, installation, vacuuming, and
recharge cost $750.

One point is this: If you can find ONE immigrant tradesman, you've got
access, probably, to lots of others (roofers, sewer replacement, concrete
work, etc.). No, they're not bonded, insured, and so forth, but the proof is
in the pudding. If the job works, you're good. Besides, I know where Lewis,
the guy who did the work, lives - next door to my son - and Lewis knows I
have a gun.

Feel free to disagree, but this technique works for me.


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On 3/5/2013 2:45 PM, HeyBub wrote:
The Daring Dufas wrote:

If gfretw was the inspector in charge I would do what he said but I
have to go by what the inspectors here and now require. I also go by
the manufacturers requirements unless they clash with the inspector
who has final say. The city here actually has stricter guidelines in
some areas than the NEC. Here, they want the circuit and wire gauge
to match no matter what the load is with the only difference being
that HACR rated breakers be used on AC and refrigeration units.
Understand that the temperature rating of the insulation also
determines the amp carrying specification of the wiring for both
copper and aluminum. ^_^


I replaced my 3-ton a/c unit after its 12-year old predecessor croaked as a
result of Hurricane Yikes*. The chap who replaced it said I could also swap
out the 40-amp breaker with a 30-amp one inasmuch as more modern units, mine
included, were more efficient and drew less power. Makes sense since the
original a/c unit was a builder model from the 1960's. The compressor unit,
no doubt, had been replaced, maybe more than once, before I bought the
house. But nobody every fiddled with changing the circuit breaker.

----------------
* The fellow who did the work is a Guatamalan off-the-books a/c technician.
Evidently he is part of a co-national underground network of repair people
in that he knew a guy who obtains and reconditions a/c units, some from
insurance companies after house fires. Anyway, the unit he chose was a
two-year old Trane, and the unit has been working swell for the past four
years. The whole business, compressor unit, installation, vacuuming, and
recharge cost $750.

One point is this: If you can find ONE immigrant tradesman, you've got
access, probably, to lots of others (roofers, sewer replacement, concrete
work, etc.). No, they're not bonded, insured, and so forth, but the proof is
in the pudding. If the job works, you're good. Besides, I know where Lewis,
the guy who did the work, lives - next door to my son - and Lewis knows I
have a gun.

Feel free to disagree, but this technique works for me.



Whatever works. I try to avoid government involvement in business
whenever I can because it tends to increase the cost of everything
but at the same time I'll do quality work and not slipshod crap which
gives folks a reason to complain to a government puke. ^_^

TDD
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What about the outside disconnect? It is just simply a "pull-out" type
disconnect, no fuses, just solid copper buss bars. I don't see any
rating for it. How do I know it's rating? Or are all these type of
disconnects just a standard rating?
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On 3/5/2013 7:20 PM, Mikepier wrote:
What about the outside disconnect? It is just simply a "pull-out" type
disconnect, no fuses, just solid copper buss bars. I don't see any
rating for it. How do I know it's rating? Or are all these type of
disconnects just a standard rating?


I personally don't like the pull out disconnects because they can
corrode from mishandling and pranksters can make off with the pull
out. I use the Square D dummy breaker in a rain proof box. It looks
like a standard Square D QO breaker but with no over current protection
and a real circuit breaker will actually snap-in in its place. ^_^

http://preview.tinyurl.com/afjtpkh

http://preview.tinyurl.com/bav4wkr

TDD
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Default What size wiring for Central A/C compressor?

The Daring Dufas wrote:
On 3/5/2013 7:20 PM, Mikepier wrote:
What about the outside disconnect? It is just simply a "pull-out"
type disconnect, no fuses, just solid copper buss bars. I don't see
any rating for it. How do I know it's rating? Or are all these type
of disconnects just a standard rating?


I personally don't like the pull out disconnects because they can
corrode from mishandling and pranksters can make off with the pull
out. I use the Square D dummy breaker in a rain proof box. It looks
like a standard Square D QO breaker but with no over current
protection and a real circuit breaker will actually snap-in in its
place. ^_^


As for pranksters, my disconnect has a a padlock, the key to which is kept
in the main circuit-breaker box (which also has a padlock).


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