I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

I assume this a US question.

Yes and no. The very fact that you needed to ask sounds like this
might be a bit too technical for you.

220 volts does not require a neutral.
110 absolutely must have.
Both should have a ground.

How many wires and what colors in your receptacle? Let's assume
you have red/black/white/green. Use a volt tester and check the
voltages:

between red and black you should get 220
between red and white you should get 110
between black and white you should get 110
between white and green you should get none.

If all this is true, replace the existing receptacle using either
blk or red on the brass screw / white on the silver screw / green
on the green screw / cap off the unused blk or red (or better,
take it off at the breaker).

If this is not what you have, hire an electrician.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




wrote in message
ps.com...
I purchased a thru-the-wall A/C unit that runs 115V to replace an
out
A/C and didn't realized the old ran on 230V. Is there an easy
way to
convert the 230V outlet to 115V?

wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?


sure, replace the double pole breaker in your breaker box with a
corresponding amp rating single pole breaker. (never go bigger unless
you are sure that the wire gauge is acceptable to use with the breaker
you are proposing to use) Connect the black wire to the new breaker,
connect the white wire to the neutral bus. Replace the receptacle with
a 115V receptacle. Cover the hole in your breaker panel's cover. Et voila.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

In article om, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

Probably, but that depends partly on the amperage rating of the existing
circuit, and that of the new A/C unit. If the new unit is rated at higher
amperage than the existing circuit (e.g. you have a 15A circuit, and a 17A air
conditioner), you'll need to replace everything.

BTW -- it's 120 / 240 now. Hasn't been 115 / 230 for a long, long time.

Assuming that the amperage ratings match up, here's how you can go about it:

First, obtain a 120V receptacle of the proper rating. You might need a 20A
receptacle, depending on what the new A/C requires.

Next, test the outlet with a circuit tester or voltmeter to verify that it's
live. Turn off the circuit breaker and test it again, to verify that it's
dead. (This protects you against the possibility that a faulty tester is
incorrectly showing a live circuit to be dead.)

Then remove the existing receptacle from the box in the wall -- DON'T
disconnect any wires from it yet -- and look at what's connected to it, and
what other wires may be present in the box.

Most likely, there will be three wires connected to the receptacle (black,
white, and bare), and no other wires present. If not, STOP NOW, and post here
again, describing what you *do* have -- and ignore the rest of my reply.

Remove all three wires from the existing 240V receptacle, and connect them to
the new 120V receptacle as follows:
- black to the brass-colored screw
- white to the silver-colored screw
- bare to the green screw
and install the receptacle in the box in the wall.

Take the cover off the circuit breaker panel. Disconnect the white wire from
the circuit breaker for this circuit (leaving the black wire in place).
Connect the white wire to the neutral bus bar in the breaker panel. (This is a
long bar with many screw terminals, that already has numerous white wires
connected to it.)

Turn the breaker back on, and check the new receptacle with one of those
plug-in circuit testers that shows you whether it's wired correctly. Or test
with a voltmeter: you should see 120V between hot and neutral, 120V between
hot and ground, and 0V between neutral and ground.

If everything tests correctly, put a cover plate on the receptacle, plug in
your A/C, and enjoy the cool.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

On Thu, 14 Jun 2007 17:29:57 -0700, wrote:

I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

On Jun 14, 10:23 pm, mm wrote:
On Thu, 14 Jun 2007 17:29:57 -0700, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.

So, yer both right.

J

On Fri, 15 Jun 2007 06:27:59 -0700, wrote:

On Jun 14, 10:23 pm, mm wrote:
On Thu, 14 Jun 2007 17:29:57 -0700, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.

So, yer both right.

Thank you.

J

On Fri, 15 Jun 2007 06:27:59 -0700, wrote:

On Jun 14, 10:23 pm, mm wrote:
On Thu, 14 Jun 2007 17:29:57 -0700, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.


How would you get that?

BTW, my outlets usually supply exactly 120V RMS.

So, yer both right.

J
--
Mark Lloyd
http://notstupid.laughingsquid.com

"So far as I can remember, there is not one word
in the Gospels in praise of intelligence."
--Bertrand Russell

According to Mark Lloyd :
On Fri, 15 Jun 2007 06:27:59 -0700, wrote:

On Jun 14, 10:23 pm, mm wrote:
On Thu, 14 Jun 2007 17:29:57 -0700, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.


How would you get that?

BTW, my outlets usually supply exactly 120V RMS.

Unloaded.

Power specifications take into account permissible voltage drop
under load. The permissible voltage drop includes the +/- 5%
tolerance or so permitted at your service panel's 120/240V
and the 5% or so voltage drop permitted over the house wiring
and supply cords.

Which basically means that house power is allowed to be (by code
and regulation) anywhere between about 110V and 130V.

In other words, some people call it 110V, others call it 120V,
and some people pick numbers in between. And of course, most
volt meters aren't very good at this accuracy on AC house power
either.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Mon, 18 Jun 2007 18:57:11 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Fri, 15 Jun 2007 06:27:59 -0700, wrote:

On Jun 14, 10:23 pm, mm wrote:
On Thu, 14 Jun 2007 17:29:57 -0700, wrote:
I purchased a thru-the-wall A/C unit that runs 115V to replace an out
A/C and didn't realized the old ran on 230V. Is there an easy way to
convert the 230V outlet to 115V?

If I recall correctly, 220v ACs are more efficient than 110. CAn you
return the one you have and get one that works on 220/30/40.

(Doug, I live in the 110/220 world and don't plan to move until I
reach the Next World.)

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.


How would you get that?

BTW, my outlets usually supply exactly 120V RMS.

Unloaded.

Power specifications take into account permissible voltage drop
under load. The permissible voltage drop includes the +/- 5%
tolerance or so permitted at your service panel's 120/240V
and the 5% or so voltage drop permitted over the house wiring
and supply cords.

Which basically means that house power is allowed to be (by code
and regulation) anywhere between about 110V and 130V.

In other words, some people call it 110V, others call it 120V,
and some people pick numbers in between. And of course, most
volt meters aren't very good at this accuracy on AC house power
either.

OK, about the voltage drop and permissible voltage ranges. However
that doesn't seem to explain how you got that specific number (117).
Are you measuring peak voltage somewhere and calculating from that?

The outlets in my house are normally supplying 120V with no load
(other than the kill-a-watt meter). Where is the 117V in that?

BTW, The voltage numbers I remember hearing about are 110V, 115V,
117V, 118V, 120V, 120V and 220V, 230V, 235V, 240V.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"So far as I can remember, there is not one word
in the Gospels in praise of intelligence."
--Bertrand Russell

Chris Lewis wrote:

....
Which basically means that house power is allowed to be (by code
and regulation) anywhere between about 110V and 130V.
....

Can you tell me which NEC sections say that?

According to Mark Lloyd :
On Mon, 18 Jun 2007 18:57:11 -0000, (Chris
Lewis) wrote:

Power specifications take into account permissible voltage drop
under load. The permissible voltage drop includes the +/- 5%
tolerance or so permitted at your service panel's 120/240V
and the 5% or so voltage drop permitted over the house wiring
and supply cords.

OK, about the voltage drop and permissible voltage ranges. However
that doesn't seem to explain how you got that specific number (117).
Are you measuring peak voltage somewhere and calculating from that?

The outlets in my house are normally supplying 120V with no load
(other than the kill-a-watt meter). Where is the 117V in that?

Stick a toaster on the line, and you'll see something _other_
than 120V ;-)

[Our house power, according to my reasonably accurate meter,
is 127V. Which makes sense where we live.]

I seem to recall somewhere seeing that 117V is the exact calculated
RMS value from some specific regulatory "peak" _nominal_ voltage.

The point being that because of resistive losses and power station
management, it is _allowed_ (by code and power regulations) to vary
a fair bit. This means in practise there's a considerable variation
in the voltage present on a given outlet, moreso when you figure that
many voltmeters aren't very accurate on AC RMS voltages either.

BTW, The voltage numbers I remember hearing about are 110V, 115V,
117V, 118V, 120V, 120V and 220V, 230V, 235V, 240V.

Think about them as being dialects of "power speak", all meaning the
same thing in the end.

One of the reasons for that is pragmatic - Eg: motor HP and current draw
are often specified at the lower end of the permitted range, because
that's worst-case for heat generation/ultimate limits on the device.

Other reasons are simply habit - what grandpop used to call it.

Like, you say ToMAYto, and I say ToMAWto, but they're both
red fruit ;-)
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Thu, 28 Jun 2007 20:24:57 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Mon, 18 Jun 2007 18:57:11 -0000, (Chris
Lewis) wrote:

Power specifications take into account permissible voltage drop
under load. The permissible voltage drop includes the +/- 5%
tolerance or so permitted at your service panel's 120/240V
and the 5% or so voltage drop permitted over the house wiring
and supply cords.

OK, about the voltage drop and permissible voltage ranges. However
that doesn't seem to explain how you got that specific number (117).
Are you measuring peak voltage somewhere and calculating from that?

The outlets in my house are normally supplying 120V with no load
(other than the kill-a-watt meter). Where is the 117V in that?

Stick a toaster on the line, and you'll see something _other_
than 120V ;-)

[Our house power, according to my reasonably accurate meter,
is 127V. Which makes sense where we live.]


Voltage drop with load. I've made different tests. Usually with that
meter in an outlet, then plugging in a hair dryer and seeing the
voltage change. The amount of voltage drop would vary greatly (usually
in the 1V-5V range) depending on things like amount of load and
distance from panel.

I was wondering why the SPECIFIC value of 117V was mentioned in an
earlier post.

I seem to recall somewhere seeing that 117V is the exact calculated
RMS value from some specific regulatory "peak" _nominal_ voltage.


In college I was taught that peak voltage = 1.414 * RMS voltage. In
that case, 117V RMS would equal 165V peak. The post I responded
mentioned "110 to 120", supposedly referring to the permitted range of
supply voltages. This differs from 165V.

The point being that because of resistive losses and power station
management, it is _allowed_ (by code and power regulations) to vary
a fair bit. This means in practise there's a considerable variation
in the voltage present on a given outlet, moreso when you figure that
many voltmeters aren't very accurate on AC RMS voltages either.

BTW, The voltage numbers I remember hearing about are 110V, 115V,
117V, 118V, 120V, 120V and 220V, 230V, 235V, 240, 250V.


For some unknown reason, 250V got neglected when I made that list so I
fixed the omission.

Think about them as being dialects of "power speak", all meaning the
same thing in the end.

One of the reasons for that is pragmatic - Eg: motor HP and current draw
are often specified at the lower end of the permitted range, because
that's worst-case for heat generation/ultimate limits on the device.


If the permitted range is still 110V to 130V, the lower end is not
117V.

Other reasons are simply habit - what grandpop used to call it.


Older people do usually refer to "110V" or "220V".

Like, you say ToMAYto, and I say ToMAWto, but they're both
red fruit ;-)

Since the text from , that I responded to got
snipped, here it is below. I was wondering where the specific number
of 117 came from:

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Never underestimate the power of stupid
people in large groups"

According to Mark Lloyd :
I was wondering why the SPECIFIC value of 117V was mentioned in an
earlier post.

That's what I was answering.

I seem to recall somewhere seeing that 117V is the exact calculated
RMS value from some specific regulatory "peak" _nominal_ voltage.


In college I was taught that peak voltage = 1.414 * RMS voltage. In
that case, 117V RMS would equal 165V peak. The post I responded
mentioned "110 to 120", supposedly referring to the permitted range of
supply voltages. This differs from 165V.

You're getting confused. 110 to 120 (or more actually like 130)
is the permitted _RMS_ supply voltage range. The sinusoidal peak is
indeed in the 165V range.

The point being that because of resistive losses and power station
management, it is _allowed_ (by code and power regulations) to vary
a fair bit. This means in practise there's a considerable variation
in the voltage present on a given outlet, moreso when you figure that
many voltmeters aren't very accurate on AC RMS voltages either.

BTW, The voltage numbers I remember hearing about are 110V, 115V,
117V, 118V, 120V, 120V and 220V, 230V, 235V, 240, 250V.

For some unknown reason, 250V got neglected when I made that list so I
fixed the omission.

Okay....

Think about them as being dialects of "power speak", all meaning the
same thing in the end.

One of the reasons for that is pragmatic - Eg: motor HP and current draw
are often specified at the lower end of the permitted range, because
that's worst-case for heat generation/ultimate limits on the device.

If the permitted range is still 110V to 130V, the lower end is not
117V.

I wasn't saying that 117V was the lower range. I was actually referring
to the practise of many motors having a _plate_ rating of thus-and-so
Amps at 110V.

Since the text from , that I responded to got
snipped, here it is below. I was wondering where the specific number
of 117 came from:

IIRC, if you calculate the actual rms voltage, a "110" or "120" volt
line is actually 117v. Of course this is nominal, since it excludes
noise and IR drops.

You answered that yourself.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Thu, 28 Jun 2007 23:39:23 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
I was wondering why the SPECIFIC value of 117V was mentioned in an
earlier post.

That's what I was answering.

I seem to recall somewhere seeing that 117V is the exact calculated
RMS value from some specific regulatory "peak" _nominal_ voltage.


In college I was taught that peak voltage = 1.414 * RMS voltage. In
that case, 117V RMS would equal 165V peak. The post I responded
mentioned "110 to 120", supposedly referring to the permitted range of
supply voltages. This differs from 165V.

You're getting confused. 110 to 120 (or more actually like 130)
is the permitted _RMS_ supply voltage range.

"110 to 120" is a quote from a particular poster. See the end of my
previous post.

The sinusoidal peak is
indeed in the 165V range.


Why would you think I'm confused? Do you disagree with what I said
about 117V RMS = 165V peak? About peak being 1.414 of RMS?

[snip]
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Never underestimate the power of stupid
people in large groups"

According to Mark Lloyd :
On Thu, 28 Jun 2007 23:39:23 -0000, (Chris
Lewis) wrote:

You're getting confused. 110 to 120 (or more actually like 130)
is the permitted _RMS_ supply voltage range.

"110 to 120" is a quote from a particular poster. See the end of my
previous post.

The sinusoidal peak is
indeed in the 165V range.

Why would you think I'm confused? Do you disagree with what I said
about 117V RMS = 165V peak? About peak being 1.414 of RMS?

Neither. I was remarking on this:

mentioned "110 to 120", supposedly referring to the permitted range of
supply voltages. This differs from 165V.

My posting did say I agree with your RMS-Peak calculations.
But saying the peak voltage isn't in the permissible (RMS) voltage
range is rather odd way of discussing this, don't you think?
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Sat, 07 Jul 2007 22:58:37 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Thu, 28 Jun 2007 23:39:23 -0000, (Chris
Lewis) wrote:

You're getting confused. 110 to 120 (or more actually like 130)
is the permitted _RMS_ supply voltage range.

"110 to 120" is a quote from a particular poster. See the end of my
previous post.

The sinusoidal peak is
indeed in the 165V range.

Why would you think I'm confused? Do you disagree with what I said
about 117V RMS = 165V peak? About peak being 1.414 of RMS?

Neither. I was remarking on this:

mentioned "110 to 120", supposedly referring to the permitted range of
supply voltages. This differs from 165V.

My posting did say I agree with your RMS-Peak calculations.
But saying the peak voltage isn't in the permissible (RMS) voltage
range is rather odd way of discussing this, don't you think?

And that's why I said it. I mentioned peak to demonstrate it NOT
explaining the use of ONE PARTICULAR VALUE (117).

BTW, I accept "110 to 130" as being more applicable than "110 to 120".
This still does not explain what is so special about that particular
value (117).
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Never underestimate the power of stupid
people in large groups"

According to Mark Lloyd :
On Sat, 07 Jul 2007 22:58:37 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Thu, 28 Jun 2007 23:39:23 -0000, (Chris
Lewis) wrote:

My posting did say I agree with your RMS-Peak calculations.
But saying the peak voltage isn't in the permissible (RMS) voltage
range is rather odd way of discussing this, don't you think?

And that's why I said it. I mentioned peak to demonstrate it NOT
explaining the use of ONE PARTICULAR VALUE (117).

BTW, I accept "110 to 130" as being more applicable than "110 to 120".
This still does not explain what is so special about that particular
value (117).

As I said before, I vaguely recollected that 117V was used in the
vernacular because it was the exact RMS conversion of some
"standardized" nominal peak voltage. But I've not been able to
find any corraboration in Google. The pecularity gets worse when
you see documents referring to main supplies as 117/230V, when
the latter really should be double the former to be logical.

We may simply have to dismiss it as a "historical quirk"/"common
usage". Eg something approaching slang.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Mon, 09 Jul 2007 14:34:45 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Sat, 07 Jul 2007 22:58:37 -0000, (Chris
Lewis) wrote:

According to Mark Lloyd :
On Thu, 28 Jun 2007 23:39:23 -0000, (Chris
Lewis) wrote:

My posting did say I agree with your RMS-Peak calculations.
But saying the peak voltage isn't in the permissible (RMS) voltage
range is rather odd way of discussing this, don't you think?

And that's why I said it. I mentioned peak to demonstrate it NOT
explaining the use of ONE PARTICULAR VALUE (117).

BTW, I accept "110 to 130" as being more applicable than "110 to 120".
This still does not explain what is so special about that particular
value (117).

As I said before, I vaguely recollected that 117V was used in the
vernacular because it was the exact RMS conversion of some
"standardized" nominal peak voltage. But I've not been able to
find any corraboration in Google. The pecularity gets worse when
you see documents referring to main supplies as 117/230V, when
the latter really should be double the former to be logical.

We may simply have to dismiss it as a "historical quirk"/"common
usage". Eg something approaching slang.

OK. Thanks for answering my question.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy