Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.

I've had my fan switch set to 'on' for the last 15 years. Costs a little
more than a 100 watt light bulb to run, but stopping and starting is worse
for an air cooled motor than leaving it on. Make sure you keep the air
filter clean. You'll sleep better, and the temperatures will be more even.

"c_shah" wrote in message
oups.com...
Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.

c_shah wrote:
Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.

It is to be used by a service man.

Bob wrote:

I've had my fan switch set to 'on' for the last 15 years. Costs a little
more than a 100 watt light bulb to run,

Are you sure about that? I think mine draws about 5 amps.

but stopping and starting is worse
for an air cooled motor than leaving it on. Make sure you keep the air
filter clean. You'll sleep better, and the temperatures will be more even.

"c_shah" wrote in message
oups.com...

Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.






--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

"c_shah" wrote in message
oups.com...
Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.


Any and all if thats what you want.

Mine only gets shut off for service. Other than that, the fans on 24-7.

I think leaving the blower running 24/7 will wear out the bearings much
faster and use electricity...

leave it on AUTO unless you need the added ventilation.

Mark

I tend to leave the fan running continuosly more in the summer time
than in the winter. But I think the motor draws more juice than a 100W
light bulb. If you have a 3/4HP blower at the very least it uses 5 amps.

It depends on your motor. Mine is 1.2 amps.

"CJT" wrote in message
...
Bob wrote:

I've had my fan switch set to 'on' for the last 15 years. Costs a little
more than a 100 watt light bulb to run,

Are you sure about that? I think mine draws about 5 amps.

but stopping and starting is worse
for an air cooled motor than leaving it on. Make sure you keep the air
filter clean. You'll sleep better, and the temperatures will be more
even.

"c_shah" wrote in message
oups.com...

Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.






--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Bob wrote:
It depends on your motor. Mine is 1.2 amps.

How many HP is your blower?

Are you sure your not referring to the combustion blower motor?

"Mikepier" wrote in message
oups.com...

Bob wrote:
It depends on your motor. Mine is 1.2 amps.

How many HP is your blower?

Are you sure your not referring to the combustion blower motor?

Ive got a 1/2HP on mine, its pulling about the same...but then, load, due to
the duct design, will play into this, and most people do not clamp a meter
on, close the door, and take a peak reading with the blower under load.

LOL! Bob, you're either leaving out some relevant facts, or
you're lying, I'm not sure which! Also, most fan motors aren't
continuous duty in the way you're claiming to use them.

What's missing from your post? Or are you just full of it?

Pop



"Bob" wrote in message
...
: I've had my fan switch set to 'on' for the last 15 years. Costs
a little
: more than a 100 watt light bulb to run, but stopping and
starting is worse
: for an air cooled motor than leaving it on. Make sure you keep
the air
: filter clean. You'll sleep better, and the temperatures will be
more even.
:
: "c_shah" wrote in message
: oups.com...
: Furnace fan can be set to "auto" and "ON", I ususally keeps
it on the
: "auto"
:
: I think when you keep the fan "ON" the fan will run
contineously while
: on "auto" it will start and stop automatically as per the
need.
:
: Does anyone know which weather condition you should keep the
fan to
: "ON"? Thanks in advance.
:
:
:

Air-cooled direct-drive blower motors can be run all the time, but you
should have a properly sized duct system, and keep your filter clean. It's
much worse to stop and start them all the time. Once those motors get going,
they have very little strain on them.

"Pop" wrote in message
...
LOL! Bob, you're either leaving out some relevant facts, or
you're lying, I'm not sure which! Also, most fan motors aren't
continuous duty in the way you're claiming to use them.

What's missing from your post? Or are you just full of it?

Pop



"Bob" wrote in message
...
: I've had my fan switch set to 'on' for the last 15 years. Costs
a little
: more than a 100 watt light bulb to run, but stopping and
starting is worse
: for an air cooled motor than leaving it on. Make sure you keep
the air
: filter clean. You'll sleep better, and the temperatures will be
more even.
:
: "c_shah" wrote in message
: oups.com...
: Furnace fan can be set to "auto" and "ON", I ususally keeps
it on the
: "auto"
:
: I think when you keep the fan "ON" the fan will run
contineously while
: on "auto" it will start and stop automatically as per the
need.
:
: Does anyone know which weather condition you should keep the
fan to
: "ON"? Thanks in advance.
:
:
:

Bob wrote:
It's
much worse to stop and start them all the time. Once those motors get going,
they have very little strain on them.



Could you explain why?

The bearings are being worn whenever the shaft turns.
What typically breaks on these,....... the bearings.

What wear is caused by starting and stopping the motor? These
typically do not have a centrifugal switch or anything like that so
what's the problem with starting and stopping?

On a normal winter day my furnace and blower run 25% of the time,
seems like a waste of energy and wear and tear on the blower bearings
to run the blower 24/7.

Mark

The last 2, 100000 btu furnaces Ive had pull apx 375 watts on a direct
drive blower. that will cost anyone at .125kwh a standard US rate apx
35$ a month run 24x7. That is a bit of a waste. No furnace blower ive
seen can pull only 1.2a under load. I think you are measuring it wrong.

At the classes I've gone to, the teachers said that stopping and starting
was worse, and that once they get up to speed, there's very little strain on
a motor of this type. I don't remember anyone ever asking them why. I always
assumed it was from the heat generated while the armature was straining to
get up to speed but still didn't have enough air flow to cool it properly.
As for the bearings, I don't know if sleeve or ball bearings makes a
difference, but I assume the blower wheel must be balanced properly to cause
minimal bearing wear.

"Mark" wrote in message
oups.com...

Bob wrote:
It's
much worse to stop and start them all the time. Once those motors get
going,
they have very little strain on them.



Could you explain why?

The bearings are being worn whenever the shaft turns.
What typically breaks on these,....... the bearings.

What wear is caused by starting and stopping the motor? These
typically do not have a centrifugal switch or anything like that so
what's the problem with starting and stopping?

On a normal winter day my furnace and blower run 25% of the time,
seems like a waste of energy and wear and tear on the blower bearings
to run the blower 24/7.

Mark

On Wed, 04 Jan 2006 18:09:44 GMT, CJT wrote:

Bob wrote:

I've had my fan switch set to 'on' for the last 15 years. Costs a little
more than a 100 watt light bulb to run,

Are you sure about that? I think mine draws about 5 amps.


My (gas) furnace consumes .14A with the fan off. 6.9A with it on.
That's with no heat.

but stopping and starting is worse
for an air cooled motor than leaving it on. Make sure you keep the air
filter clean. You'll sleep better, and the temperatures will be more even.

"c_shah" wrote in message
oups.com...

Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.




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

"Democracy is two wolves and a lamb voting on what
to have for lunch. Liberty is a well armed lamb
contesting the vote." - Benjamin Franklin

On 4 Jan 2006 10:26:17 -0800, "Mark" wrote:

I think leaving the blower running 24/7 will wear out the bearings much
faster and use electricity...


And the filter will need cleaning more often.

leave it on AUTO unless you need the added ventilation.

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

"Democracy is two wolves and a lamb voting on what
to have for lunch. Liberty is a well armed lamb
contesting the vote." - Benjamin Franklin

They make direct drive blower motors that draw less than 1 amp at 230 volts,
but I've never seen a 115 volt motor on a furnace that low.

"m Ransley" wrote in message
...
The last 2, 100000 btu furnaces Ive had pull apx 375 watts on a direct
drive blower. that will cost anyone at .125kwh a standard US rate apx
35$ a month run 24x7. That is a bit of a waste. No furnace blower ive
seen can pull only 1.2a under load. I think you are measuring it wrong.

On Wed, 4 Jan 2006 15:18:12 -0500, "CBHVAC" wrote:


"Mikepier" wrote in message
roups.com...

Bob wrote:
It depends on your motor. Mine is 1.2 amps.

How many HP is your blower?

Are you sure your not referring to the combustion blower motor?

Ive got a 1/2HP on mine, its pulling about the same...but then, load, due to
the duct design, will play into this, and most people do not clamp a meter
on, close the door, and take a peak reading with the blower under load.




I used a plug-in meter (kill-a-watt) on the furnace power cord, when I
read 6.9A.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Democracy is two wolves and a lamb voting on what
to have for lunch. Liberty is a well armed lamb
contesting the vote." - Benjamin Franklin

but it takes only a few seconds to get up to speed...

I find it hard to believe that any significant heat builds up in 5
seconds compared ot the heat that builds up runnning 24/7....

Imagine starting the blower..... then as soon as it gets up to speed,
stopping it, and checking the motor windings and armature temperature
..... compared to letting it run all day then checking the
temperature..


thanks

Mark

Mark & Bob,
The blower motors are designed to be able to run constantly without
damage to the bearings or windings. Just ask any motor manufacturer.
I have been to many motor seminars & the main failure mode is HEAT. A
motor with restricted air flow will run hot and die an early death.
Starting causes some strain on motors but dirty or restricted filters
cause overheating which will damage motors. A blower motor should last
as long as the furnace if it has enough air flow to keep it cool. That
is if it runs constantly OR cycles.

Running the fan set to on will increase humidity when cooling by as
much as 15% in high humidity climates. This is because when the
compressor shuts off the water left on the coil will re-evaporate into
the air stream. Get a data logger to record humidity and try it both
ways. I did. A Lennox manual titled "Equipment Selection in Humid
Applications" came to the same conclusion.

My fan motor on my 2.5 ton heat pump indoor unit draws 2.2 amps at 240
volts. Just over 475 watts at 0.9 power factor. at my utility rates
that is about 4 cents an hour. That is just under $30.00 per month
when running 24/7.

I leave mine set to auto. If you have cheap electricity or a different
climate or both, feel free to set it to ON.

The advantages are it will even out temperatures and filter the air
better. The disadvantages are high summer humidity in many climates,
high electric bills and drafty feeling in the winter. The best time to
run the fan set to ON is spring & fall.

Stretch

Sorry, but I never saw an air-cooled direct-drive car motor. And even if
they had one, I fail to see the benefit unless you're living in the car and
filtering the air.

"Al Moran" wrote in message
...
On Wed, 4 Jan 2006 16:00:09 -0500, "Bob" wrote:

Air-cooled direct-drive blower motors can be run all the time, but you
should have a properly sized duct system, and keep your filter clean.
It's
much worse to stop and start them all the time. Once those motors get
going,


Then i would suggest that you leave your car running all the time. You
don't have a clue.

Stretch,

Thanks for the input. I can see where setting the fan to 'on' in humid
climates can increase humidity. My experience is limited to my particular
climate. I wonder if Lennox was only talking about properly sized cooling
systems when they say "as much as 15%".

I have hydronic baseboard heat with straight air in the attic. With the
blower on, my heat is more even, because it pushes the heat back down to the
floor.



"Stretch" wrote in message
oups.com...
Mark & Bob,
The blower motors are designed to be able to run constantly without
damage to the bearings or windings. Just ask any motor manufacturer.
I have been to many motor seminars & the main failure mode is HEAT. A
motor with restricted air flow will run hot and die an early death.
Starting causes some strain on motors but dirty or restricted filters
cause overheating which will damage motors. A blower motor should last
as long as the furnace if it has enough air flow to keep it cool. That
is if it runs constantly OR cycles.

Running the fan set to on will increase humidity when cooling by as
much as 15% in high humidity climates. This is because when the
compressor shuts off the water left on the coil will re-evaporate into
the air stream. Get a data logger to record humidity and try it both
ways. I did. A Lennox manual titled "Equipment Selection in Humid
Applications" came to the same conclusion.

My fan motor on my 2.5 ton heat pump indoor unit draws 2.2 amps at 240
volts. Just over 475 watts at 0.9 power factor. at my utility rates
that is about 4 cents an hour. That is just under $30.00 per month
when running 24/7.

I leave mine set to auto. If you have cheap electricity or a different
climate or both, feel free to set it to ON.

The advantages are it will even out temperatures and filter the air
better. The disadvantages are high summer humidity in many climates,
high electric bills and drafty feeling in the winter. The best time to
run the fan set to ON is spring & fall.

Stretch

Mark Lloyd wrote:
On Wed, 4 Jan 2006 15:18:12 -0500, "CBHVAC" wrote:


"Mikepier" wrote in message
groups.com...

Bob wrote:

It depends on your motor. Mine is 1.2 amps.


How many HP is your blower?

Are you sure your not referring to the combustion blower motor?

Ive got a 1/2HP on mine, its pulling about the same...but then, load, due to
the duct design, will play into this, and most people do not clamp a meter
on, close the door, and take a peak reading with the blower under load.



I used a plug-in meter (kill-a-watt) on the furnace power cord, when I
read 6.9A.

Let''s look at it this way:

Ideally, 1hp = 746watts

If a motor delivers 1/2 hp, then its actual wattage will run over half
of this, because the motor isn't 100% efficient at converting electrical
energy into useful mechanical energy.

A half horse blower motor consumes about 400 watts.

On low speed, however, at 230 volt, the amperage draw can run down
around the 1.2 amp region.

On many newer units continuous fan is defaulted to low speed, which is
equivalent to about 1/2 the rate hp of the motor.
IOW, on low speed a half horse motor will be running at closer to 1/4
hp, or thereabouts, or somewhere in the region of 200 watts, and the amp
draw corresponding to this on 230 volts is down around the 1 amp mark.
I've seen them running under 1 amp.

hvacrmedic

On Wed, 04 Jan 2006 18:17:35 -0600, Mark Lloyd
wrote:

On 4 Jan 2006 10:26:17 -0800, "Mark" wrote:

I think leaving the blower running 24/7 will wear out the bearings much
faster and use electricity...


And the filter will need cleaning more often.

That I suppose would mean that the air in the house is cleaner.

But only a little bit

I always leave mine on auto. These are mattters of taste, and De
gustibus, no est disputandum (or something like that: There is no
disputing with regard to taste.) but I don't care if there are minor
variations in temperature, and I like the silence when the fan is off
altoghether. It would drive me crazy to have it on all the time.r.

leave it on AUTO unless you need the added ventilation.



Mark


Remove NOPSAM to email me. Please let
me know if you have posted also.

On Sun, 08 Jan 2006 00:48:04 -0500, mm
wrote:

On Wed, 04 Jan 2006 18:17:35 -0600, Mark Lloyd
wrote:

On 4 Jan 2006 10:26:17 -0800, "Mark" wrote:

I think leaving the blower running 24/7 will wear out the bearings much
faster and use electricity...


And the filter will need cleaning more often.

That I suppose would mean that the air in the house is cleaner.

But only a little bit

I always leave mine on auto. These are mattters of taste, and De
gustibus, no est disputandum (or something like that: There is no
disputing with regard to taste.) but I don't care if there are minor
variations in temperature, and I like the silence when the fan is off
altoghether. It would drive me crazy to have it on all the time.r.


A constant noise is less distracting than one that changes (on and
off) unpredictably.

BTW, I remember spending the night with someone who left the fan on
all the time, and the room I slept in was next to the furnace. I never
noticed the fan after a few minutes except once. That time, it was a
power failure.

leave it on AUTO unless you need the added ventilation.



Mark


Remove NOPSAM to email me. Please let
me know if you have posted also.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Democracy is two wolves and a lamb voting on what
to have for lunch. Liberty is a well armed lamb
contesting the vote." - Benjamin Franklin

On Sun, 08 Jan 2006 09:26:57 -0600, Mark Lloyd
wrote:

On Sun, 08 Jan 2006 00:48:04 -0500, mm
wrote:

On Wed, 04 Jan 2006 18:17:35 -0600, Mark Lloyd
wrote:

On 4 Jan 2006 10:26:17 -0800, "Mark" wrote:

I think leaving the blower running 24/7 will wear out the bearings much
faster and use electricity...


And the filter will need cleaning more often.

That I suppose would mean that the air in the house is cleaner.

But only a little bit

I always leave mine on auto. These are mattters of taste, and De
gustibus, no est disputandum (or something like that: There is no
non est disputandum.
disputing with regard to taste.) but I don't care if there are minor
variations in temperature, and I like the silence when the fan is off
altoghether. It would drive me crazy to have it on all the time.r.


A constant noise is less distracting than one that changes (on and
off) unpredictably.

To some people.

This is a matter of taste.

This I really can't spell: Chaque a sangue. Each to his own taste.

BTW, I remember spending the night with someone who left the fan on
all the time, and the room I slept in was next to the furnace. I never
noticed the fan after a few minutes except once. That time, it was a
power failure.

leave it on AUTO unless you need the added ventilation.



Mark



Remove NOPSAM to email me. Please let
me know if you have posted also.

On Sun, 08 Jan 2006 23:55:06 -0500, mm
wrote:

This is a matter of taste.

This I really can't spell: Chaque a sangue. Each to his own taste.

Chacon a son gout (there's an accent over the "a" that I'm incapable
of placing).

c_shah wrote:
Furnace fan can be set to "auto" and "ON", I ususally keeps it on the
"auto"

I think when you keep the fan "ON" the fan will run contineously while
on "auto" it will start and stop automatically as per the need.

Does anyone know which weather condition you should keep the fan to
"ON"? Thanks in advance.


The only times I've left mine on "ON" were during parties in the winter
when I'd have many guests over. The body heat generated by each guest
is enough to raise the temperature of the room a few degrees above
normal, making the furnace not run at all. After 3-4 hours the main
floor where all the guests are becomes 2-4 degrees hotter than the rest
of the house, and the air starts getting a bit stuffy from all the
people and the lack of air circulation. Often the windows will start
to fog up from the extra humidity (from all the cooking, guests talking
and drinking, etc.)

I leave the fan on ON to get better air circulation during those times.
The whole house stays at a much more comfortable and constant
temperature, the air is less humid and stuffy, and the windows don't
fog up.

wrote in message
oups.com...

The only times I've left mine on "ON" were during parties in the winter
when I'd have many guests over. The body heat generated by each guest
is enough to raise the temperature of the room a few degrees above
normal, making the furnace not run at all. After 3-4 hours the main
floor where all the guests are becomes 2-4 degrees hotter than the rest
of the house, and the air starts getting a bit stuffy from all the
people and the lack of air circulation. Often the windows will start
to fog up from the extra humidity (from all the cooking, guests talking
and drinking, etc.)


....and it's really important to do that if you're serving a bean dish like
chili ;-)

Patrick

Is there something wrong with my furnace? If I leave the fan "ON"
there's a big boom when the heat kicks on when the gas lights. I just
assumed that the gas was being sucked up by the fan and torched when it
lit.

If I leave it on "AUTO" it works just fine.

johnny wrote:

Is there something wrong with my furnace? If I leave the fan "ON"
there's a big boom when the heat kicks on when the gas lights. I just
assumed that the gas was being sucked up by the fan and torched when it
lit.

If I leave it on "AUTO" it works just fine.

That does not sound normal to me.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Yeah. I better just leave it on "AUTO".

johnny wrote:
Yeah. I better just leave it on "AUTO".

Yeah, that you can pretend that the heat exchanger isn't cracked.

hvacrmedic

Ignorance is bliss. What I don't know about can't hurt me.

johnny wrote:

Ignorance is bliss. What I don't know about can't hurt me.

What you don't know can certainly hurt you.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Patrick Cleburne wrote:
wrote in message
oups.com...

The only times I've left mine on "ON" were during parties in the winter
when I'd have many guests over. The body heat generated by each guest
is enough to raise the temperature of the room a few degrees above
normal, making the furnace not run at all. After 3-4 hours the main
floor where all the guests are becomes 2-4 degrees hotter than the rest
of the house, and the air starts getting a bit stuffy from all the
people and the lack of air circulation. Often the windows will start
to fog up from the extra humidity (from all the cooking, guests talking
and drinking, etc.)



...and it's really important to do that if you're serving a bean dish like
chili ;-)

Patrick


Uhh, chili isn't a bean dish, it is a green dish.

Thanks for the input. I can see where setting the fan to 'on' in humid
climates can increase humidity. My experience is limited to my
particular
climate. I wonder if Lennox was only talking about properly sized
cooling
systems when they say "as much as 15%".


I have hydronic baseboard heat with straight air in the attic. With the

blower on, my heat is more even, because it pushes the heat back down
to the
floor.





Bob, Yhe 15% was what I measured with my data logger using my system.
My unit is properly sized. Lennox does not give a percentage in their
manual.

Stretch