Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You're joking, right? You expect somebody to give you a figure without
knowing the size of your furnace or the size of house?

Hint: a twenty million BTU furnace is going to warm a dollhouse a bit
faster than a bic lighter will warm up the taj mahal.

KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?


It depends.


steve

KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

FWIW, I have my programmable thermostat set to let the house cool about
5 degrees during the day when I'm not here, and I think it takes about
an hour to bring it back up to temp, so I would say 4-5 degrees per hour
isn't unreasonable. Your experience seems to be in the ballpark,
particularly given the cold outdoor temperature. As the other posters
have pointed out, there are many variables involved -- furnace size,
house size, insulation effectiveness, outdoor temperature, etc.

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

"KLS" wrote in message
...
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

There are many factors. Size of furnace, insulation, number of windows, day
or night, opening of the door, amount and type of furnishings, etc. No one
can say for sure without a lot of calculations, but that does not seem
unreasonable. There was a lot of sensible heat lost that has to be replaced
and that takes a lot of time..

On Jan 25, 7:53*pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

* 2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

I guess mine is way oversize, i can pick up easily 10 degrees per 1/2
hour. I have the unoccupied downstairs set to 55 over night, & brought
up to 68 at 6:30 am. I've never seen it not make 68 by 7:00 even when
it is in the 20s outside.

"KLS" wrote in message
...
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

I turn my heat off at nights and when we are not home. If it is 60 in the
house, it takes about an hour to warm it up to 72. If it takes 7 hours to
warm your house that much, I would wonder if your insulation is particularly
poor or if your furnace is undersized.

If this is gas or propane fuel, windows are excellent and insulation
is right, then that is a long time. However, if you have a heat pump,
that sounds about right. Activate the emergency heat option which will
use the resistive heat strips and watch your electric meter whirl.

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

On Jan 25, 5:47*pm, KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

Funny that you ask this question.....I have to have done the
expereiment on three houses

Two in Orange COunty, Ca.

One is a 1 1/2 story 1930 ....no wall insulation but ~R30 in the
attics.....on cold (for SoCal) winter day of about 50F outside,
about 5 or 6F degs per hour

Second on is a one story ranch iwth blown in cellulose attic
insulation......about the same performance

the last home is an eastern sierra two story lots of wall & ceiling
insulation, propane heat...takes about 3 or 4 hours to go from 55F to
70F

your temp rise of 2F deg per hours seems a bit on the low end in my
experience but not hugely unreasonable...a furnace needs to be able to
maintain the house at a reasonable temperature......how quickly it
gets there isn't really all that important.

what is the out side temp (I'm guessing in the 20's?)

an important thing to check would be the temp rise across the furnace

But I'm sure Bubba will jumping right in with a helpful addition
(along with his typical serving of insults) to this thread being the
furnace expert that he is

cheers
Bob

"Tom Kendrick" wrote in message
...
If this is gas or propane fuel, windows are excellent and insulation
is right, then that is a long time. However, if you have a heat pump,
that sounds about right. Activate the emergency heat option which will
use the resistive heat strips and watch your electric meter whirl.


Usually the heat strips come on anytime you are more than about 3 or 4 deg
low. If the heat pump is turned up about 2 deg at a time they will not come
on , but if it is moved from 45 to 65 deg then they probably will.
Also at 20 deg the heatpump is not too efficiant and it might as well be
using the heat strips.

On Sun, 25 Jan 2009 19:30:24 -0800 (PST), Eric in North TX
wrote:

On Jan 25, 7:53*pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

* 2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

I guess mine is way oversize, i can pick up easily 10 degrees per 1/2
hour. I have the unoccupied downstairs set to 55 over night, & brought
up to 68 at 6:30 am. I've never seen it not make 68 by 7:00 even when
it is in the 20s outside.

The length of time the temp was low makes a difference. The thermal
mass of the structure and contents make a diference that becomes
greater if it has all chilled to match the lower temps. That stuff
takes a long time to heat back up.

On Mon, 26 Jan 2009 06:21:32 -0500, wrote:

On Jan 25, 7:53*pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

* 2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

The length of time the temp was low makes a difference. The thermal
mass of the structure and contents make a diference that becomes
greater if it has all chilled to match the lower temps. That stuff
takes a long time to heat back up.

Yes, the house was chilled for probably 12 hours (the motor died
overnight, and the outdoor temps at that point were single digits).
House was built in 1930, 2 floors, has numerous windows, full
basement, full attic, not well insulated, but has storm doors and
windows all around. Furnace is a York 2-stage Diamond Deluxe 95,
installed in 2003. We live by Lake Ontario. But this new motor
doesn't seem to be heating up as quickly as the previous one did; the
old one used to be able to get the house from 60F to 65F in an hour,
and we're still not up to temperature 1.5 hours later this morning, so
I'll be calling the HVAC company to check this.

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

If I turned my furnace off & let the house get to 45- then turned it
on [while it was 20 with wind] I imagine it would take 1 -1 1/2 hours
of running to bring the house up to 65.

But my furnace was designed to keep the house at 70 when it was
30below outside- and that was with old, drafty windows & no
insulation.

If 20 is about as cold as it gets where you live- and if it was 45 for
some time so all the mass had to be re-heated- and if you've got room
for improvement in your windows and insulation- then don't worry about
your furnace. Work on the insulation.

You say you "had the blower motor replaced". That implies that some
guy who knows a whole lot more about your setup was in your house.
What did he/she say?

Jim

On Jan 26, 7:48*am, Jim Elbrecht wrote:
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

If I turned my furnace off & let the house get to 45- then turned it
on [while it was 20 with wind] *I imagine it would take 1 -1 1/2 hours
of running to bring the house up to 65.

But my furnace was designed to keep the house at 70 when it was
30below outside- and that was with old, drafty windows & no
insulation.

If 20 is about as cold as it gets where you live- and if it was 45 for
some time so all the mass had to be re-heated- and if you've got room
for improvement in your windows and insulation- then don't worry about
your furnace. * Work on the insulation.

You say you "had the blower motor replaced". *That implies that some
guy who knows a whole lot more about your setup was in your house.
What did he/she say?

Jim


With the house thoroughly chilled to around 50, with an outside temp
in the 30s, I'd say my forced air will do about 4 or 5 deg an hour.
So, I'd agree that 2 deg an hour sounds on the low side.

"KLS" wrote in message
...
On Mon, 26 Jan 2009 06:21:32 -0500, wrote:

On Jan 25, 7:53 pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

The length of time the temp was low makes a difference. The thermal
mass of the structure and contents make a diference that becomes
greater if it has all chilled to match the lower temps. That stuff
takes a long time to heat back up.

Yes, the house was chilled for probably 12 hours (the motor died
overnight, and the outdoor temps at that point were single digits).
House was built in 1930, 2 floors, has numerous windows, full
basement, full attic, not well insulated, but has storm doors and
windows all around. Furnace is a York 2-stage Diamond Deluxe 95,
installed in 2003. We live by Lake Ontario. But this new motor
doesn't seem to be heating up as quickly as the previous one did; the
old one used to be able to get the house from 60F to 65F in an hour,
and we're still not up to temperature 1.5 hours later this morning, so
I'll be calling the HVAC company to check this.

Measure the input and output temps of the unit while it is firing and blowing.
Are they within the specification listed in the installation manual?

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
Depends how many BTUs the furnace output is, as well as how much heat
loss the house has. Also depends how much thermal mass. If it needs to
heat up a lot of masonry it will take longer than heating up a lot of
stud-framed walls with good insulation.

On Jan 25, 7:53*pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

* 2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

A minor quibble: 20 degrees in 7 hours is (much closer to) 3 degrees
per hour. -- H

"Bubba" wrote in message
...
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat is getting transferred in.

On Mon, 26 Jan 2009 07:48:40 -0500, Jim Elbrecht
wrote:

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
[cut]
If 20 is about as cold as it gets where you live- and if it was 45 for
some time so all the mass had to be re-heated- and if you've got room
for improvement in your windows and insulation- then don't worry about
your furnace. Work on the insulation.

Yes: when I find time, I'm going to be calling for a polyurethane
closed cell insulation install quote for the box band of the house,
which should be fairly easy/inexpensive, all factors considered.

You say you "had the blower motor replaced". That implies that some
guy who knows a whole lot more about your setup was in your house.
What did he/she say?

The HVAC company that installed the furnace has been here four times
in just over 2 weeks. The first time was when the inducer blower died
on a Friday night; Saturday morning the tech checked a bunch of
things, decided the motor wasn't dead, and propped up the long
horizontal PVC exhaust pipes to correct a sag that apparently was
preventing gases from exhausting properly.

That got the motor going for another two weeks until this past
Saturday night when it died again. A second tech came over, checked
the system, determined the motor was dead, but was able to get it
going again. He told me to call again if it didn't keep working. It
died overnight, so I called Sunday morning (yesterday) and told him we
really needed to replace the motor, per his diagnosis. He was able to
get one and came over to install it, and all was more or less well,
except that the house took 7 hours to warm up when it had taken about
3 with the previous motor the previous episode.

This morning a third tech came over and replaced the condensate pump
(gratis as he broke off something on it) plus the vinyl condensate
discharge tubing (which I asked for, as ours was pretty gunked up
after almost 6 years in service). We agreed to do this after he found
several kinks that I'd asked the first tech about, which that tech
dismissed. Anyway, all seems well now; I will be watching tomorrow
morning to see how quickly the furnace brings the house to the
called-for temp (it took almost 2 hours to bring the house up 5
degrees F this morning and used to take one hour with the old motor).
Tonight will be low teens, tomorrow mid teens, so pray for us all!

"Zootal" wrote in message
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat is getting transferred in.


Heat a pan on the stove. Quickly smack it with your hand. Now hold you
hand for 2 seconds. Now hold your hand on it for 10 seconds. Did the
fastest speed give you the most heat?

Same with the air blowing across the heat exchanger. There is only a given
amount of heat available and the longer the residence time, the hotter it
will get and it can them move the heat to another location. Cool air then
replaces the heated air. Check this out with your car heater as it warms up
on a cold day. Run the blower speed up and down and see how the temperature
changes.

You may have other issues with your furnace too. You mentioned a sagging
PVC pipe, kinks in the condensate drain, other parts were replaced. First,
it sounds like a hack did the original install. Some of these little errors
may be causing the heat exchanger to cycle off and on too frequently or it
is not reaching temperature.

While it is nice that the tech can resurrect motors from the dead, I think
perhaps, you need a new service company.

On Mon, 26 Jan 2009 21:22:47 -0500, KLS wrote:

On Mon, 26 Jan 2009 07:48:40 -0500, Jim Elbrecht
wrote:

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
[cut]
If 20 is about as cold as it gets where you live- and if it was 45 for
some time so all the mass had to be re-heated- and if you've got room
for improvement in your windows and insulation- then don't worry about
your furnace. Work on the insulation.

Yes: when I find time, I'm going to be calling for a polyurethane
closed cell insulation install quote for the box band of the house,
which should be fairly easy/inexpensive, all factors considered.

You say you "had the blower motor replaced". That implies that some
guy who knows a whole lot more about your setup was in your house.
What did he/she say?

The HVAC company that installed the furnace has been here four times
in just over 2 weeks. The first time was when the inducer blower died
on a Friday night; Saturday morning the tech checked a bunch of
things, decided the motor wasn't dead, and propped up the long
horizontal PVC exhaust pipes to correct a sag that apparently was
preventing gases from exhausting properly.

That got the motor going for another two weeks until this past
Saturday night when it died again. A second tech came over, checked
the system, determined the motor was dead, but was able to get it
going again. He told me to call again if it didn't keep working. It
died overnight, so I called Sunday morning (yesterday) and told him we
really needed to replace the motor, per his diagnosis. He was able to
get one and came over to install it, and all was more or less well,
except that the house took 7 hours to warm up when it had taken about
3 with the previous motor the previous episode.

This morning a third tech came over and replaced the condensate pump
(gratis as he broke off something on it) plus the vinyl condensate
discharge tubing (which I asked for, as ours was pretty gunked up
after almost 6 years in service). We agreed to do this after he found
several kinks that I'd asked the first tech about, which that tech
dismissed. Anyway, all seems well now; I will be watching tomorrow
morning to see how quickly the furnace brings the house to the
called-for temp (it took almost 2 hours to bring the house up 5
degrees F this morning and used to take one hour with the old motor).
Tonight will be low teens, tomorrow mid teens, so pray for us all!

So it is not the "blower motor" that was replaced but the "eductor
fan" or "combustion purge fan"

On Mon, 26 Jan 2009 19:35:04 -0500, Bubba
wrote:

On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba
Only problem, bubba, is he didn't evenask the right question - it
wasn't the blower fan motoer that was replaced. It's the cumbustion
purge blower, or eductor fan.

On Mon, 26 Jan 2009 17:09:24 -0800, "Zootal"
wrote:


"Bubba" wrote in message
.. .
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat is getting transferred in.

Something called delta T

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat is getting transferred in.

Something called delta T

Delta T is highest when the air flowing over the hot surface is coldest. Max
delta T = max heat transferred. This happens when the airflow is fastest
because if the air flow is slower, it gets hotter because it is in contact
with the heated surface longer. Reduced delta T means less heat transferred
from hot surface to air and then to house. Which make me think that you want
higher air flow, not lower.

On Mon, 26 Jan 2009 22:02:22 -0500, "Ed Pawlowski"
wrote:

You may have other issues with your furnace too. You mentioned a sagging
PVC pipe, kinks in the condensate drain, other parts were replaced. First,
it sounds like a hack did the original install. Some of these little errors
may be causing the heat exchanger to cycle off and on too frequently or it
is not reaching temperature.

While it is nice that the tech can resurrect motors from the dead, I think
perhaps, you need a new service company.

Well, the furnace was installed in April 2003, and that run of PVC
pipe is 20 feet long, so five years of gravity apparently became
persuasive.

On Mon, 26 Jan 2009 22:28:40 -0500, wrote:

So it is not the "blower motor" that was replaced but the "eductor
fan" or "combustion purge fan"

All three terms apply, plus a fourth that I find on my receipts:
inducer blower. The tech called it a blower motor, fyi.

Bubba wrote:
On Mon, 26 Jan 2009 17:09:24 -0800, "Zootal"
wrote:

"Bubba" wrote in message
...
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house 45F to 65F. This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba
Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat is getting transferred in.


Hey Zoot. Think of it this way:
Lets take a 100,000 btu furnace and pull the blower and motor out of
it. Now install a bathroom fart fan in its place. Turn it all on. What
happens? You get an extremely high temperature with almost no air
movement.
Now, lets take that same furnace and install a 4 foot wide 4 blade fan
with a 50 hp motor turning at 30,000 rpm. Now tell me how much heat
you feel on the outlet side of that furnace.
Answer: None
It all needs to be done within a range. Thats why motors have 3 and 4
blower speeds. Its so you can set the heating blower speed and cooling
blower speed to fall within a temperature rise or drop across the heat
exchanger or cooling coil.
Clear as mud now or are you one of those guys with an EE degree?
Bubba

Exactly correct. That info applies in automobiles also . You'll always
get colder air from your air conditioner if you drop the blower a notch
or two. We (as mechanics) would always measure the temp of an air
conditioner with the blower on medium, and the mode on recirc. (max)

steve

Hey Zoot. Think of it this way:
Lets take a 100,000 btu furnace and pull the blower and motor out of
it. Now install a bathroom fart fan in its place. Turn it all on. What
happens? You get an extremely high temperature with almost no air
movement.
Now, lets take that same furnace and install a 4 foot wide 4 blade fan
with a 50 hp motor turning at 30,000 rpm. Now tell me how much heat
you feel on the outlet side of that furnace.
Answer: None

So, if you have a 50 hp motor turning at 30,000, how hot is the heated
surface inside the heater? Real hot? Not very hot because of the blast of
air going across it?

If you answered real hot, then how can that be with a blast of air going
across it?

If you answerd not very hot, then were did the heat go?

Exactly correct. That info applies in automobiles also . You'll always
get colder air from your air conditioner if you drop the blower a notch or
two. We (as mechanics) would always measure the temp of an air
conditioner with the blower on medium, and the mode on recirc. (max)

steve


Are you going to tell me next that if you take your thermostat out of your
car's cooling system that the engine will overheat?

On Jan 27, 9:24*pm, "Zootal" wrote:
Exactly correct. *That info applies in automobiles also . *You'll always
get colder air from your air conditioner if you drop the blower a notch or
two. *We (as mechanics) would always measure the temp of an air
conditioner with the blower on medium, and the mode on recirc. (max)

steve

Are you going to tell me next that if you take your thermostat out of your
car's cooling system that the engine will overheat?

No it will run cold and under perform due to not maintaining proper
operating temperature at least in the winter.
You can overheat one by upping the flow of water to the point that it
passes through too quickly to absorb the heat.

Eric in North TX wrote:
On Jan 25, 7:53 pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. The new motor was
assigned the task of warming the house from 45F to 65F. This took it
7 hours, which seems like a long time.
How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

I guess mine is way oversize, i can pick up easily 10 degrees per 1/2
hour. I have the unoccupied downstairs set to 55 over night, & brought
up to 68 at 6:30 am. I've never seen it not make 68 by 7:00 even when
it is in the 20s outside.
Hmm,
Oversized furnace won't be very efficient.

Zootal wrote:
Exactly correct. That info applies in automobiles also . You'll always
get colder air from your air conditioner if you drop the blower a notch or
two. We (as mechanics) would always measure the temp of an air
conditioner with the blower on medium, and the mode on recirc. (max)

steve


Are you going to tell me next that if you take your thermostat out of your
car's cooling system that the engine will overheat?




I guess i just assumed that anyone with any mechanical knowledge knew
that. The water actually runs cooler, but the metal parts run hotter.
Especially in the back of the heads on a v-8. The thermostat actually
provides a necessary restriction even when wide open that is required to
make the proper flow to the back end of the block. If you insist on
running no 'stat, the it's best to just take the innards from one and
install the outer ring.

steve

On Tue, 27 Jan 2009 19:24:06 -0800, "Zootal"
wrote:

Exactly correct. That info applies in automobiles also . You'll always
get colder air from your air conditioner if you drop the blower a notch or
two. We (as mechanics) would always measure the temp of an air
conditioner with the blower on medium, and the mode on recirc. (max)

steve


Are you going to tell me next that if you take your thermostat out of your
car's cooling system that the engine will overheat?


On SOME cars, they actually WILL.

On Tue, 27 Jan 2009 21:14:32 -0700, Tony Hwang
wrote:

Eric in North TX wrote:
-snip-
I guess mine is way oversize, i can pick up easily 10 degrees per 1/2
hour. I have the unoccupied downstairs set to 55 over night, & brought
up to 68 at 6:30 am. I've never seen it not make 68 by 7:00 even when
it is in the 20s outside.
Hmm,
Oversized furnace won't be very efficient.

No- but if it gets to 30 below then the furnace is designed for a 100
degree temp difference. By design, when it is 20 out the furnace is
double the size it needs to be. But most of us have just one
furnace. [and those of us with 30 yr old furnaces probably only have
one fan speed]

Jim
[and to save anyone the trouble of posting 'you should replace that
old beast' - Maybe I will someday, but it tests at 85%, I know all of
its *very simple* parts intimately & I only burn 400 gallons of oil a
yr so I'm not in a rush]

a better question is why would one want to raise temperature 20
degrees?

if your leaving the home cool to save energy thats good.

the OP could add some extra heating like a couple gas wall heaters on
a master timer switch to help reheat when you arrive home fast.turn
knob trips on extra heat for 30 minutes to help with re heat

new furnaces are sized for efficency and lack the BTUs to raise the
home fast.

adding a wall heater or other gas heater solves that and is a nice
back up if your main heating plant fails

On Jan 26, 6:35*pm, Bubba wrote:
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Of course it doesnt get to zero where you are at, or does it.

On Jan 27, 8:15*am, Bubba wrote:
On Mon, 26 Jan 2009 17:09:24 -0800, "Zootal"





wrote:

"Bubba" wrote in message
.. .
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat *is getting transferred in.

Hey Zoot. Think of it this way:
Lets take a 100,000 btu furnace and pull the blower and motor out of
it. Now install a bathroom fart fan in its place. Turn it all on. What
happens? You get an extremely high temperature with almost no air
movement.
Now, lets take that same furnace and install a 4 foot wide 4 blade fan
with a 50 hp motor turning at 30,000 rpm. Now tell me how much heat
you feel on the outlet side of that furnace.
Answer: None
It all needs to be done within a range. Thats why motors have 3 and 4
blower speeds. Its so you can set the heating blower speed and cooling
blower speed to fall within a temperature rise or drop across the heat
exchanger or cooling coil.
Clear as mud now or are you one of those guys with an EE degree?
Bubba- Hide quoted text -

- Show quoted text -

Whats an EE degree, is that something you just avoided. Here everyone
goes for Bachelors, Masters, and Doctorates.

On Jan 27, 10:14*pm, Tony Hwang wrote:
Eric in North TX wrote:

On Jan 25, 7:53 pm, dpb wrote:
KLS wrote:
Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house from 45F to 65F. *This took it
7 hours, which seems like a long time.
How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?
* 2(+/-) F/hr unless _WAY_ oversized would be pretty typical....you're
about right sounds like.

--

I guess mine is way oversize, i can pick up easily 10 degrees per 1/2
hour. I have the unoccupied downstairs set to 55 over night, & brought
up to 68 at 6:30 am. I've never seen it not make 68 by 7:00 even when
it is in the 20s outside.

Hmm,
Oversized furnace won't be very efficient.

Depends, Mine is a 96% efficient model, computer controlled. The
exhaust is so cool they use PVC to plumb it. I can't see how an
undersized one running 24-7 at max capacity could top mine cycling as
intended.
I've got a 5 ton heating and cooling about 2k fairly well insulated sq
ft. My only complaint is; it is a bit noisy on the intake side.

On Jan 27, 8:15*am, Bubba wrote:
On Mon, 26 Jan 2009 17:09:24 -0800, "Zootal"





wrote:

"Bubba" wrote in message
.. .
On Sun, 25 Jan 2009 20:47:15 -0500, KLS wrote:

Just had the blower motor replaced on our York furnace this morning.
Outside temps were 20F today with some wind. *The new motor was
assigned the task of warming the house 45F to 65F. *This took it
7 hours, which seems like a long time.

How many degrees per hour is a usual rate of temperature rise for gas
forced-air furnace?

You do know you have asked a trick question?
With the information you have given, it cant be answered.
Here let me give you and example or two so you might understand.
Where I live, we design furnaces to maintain an indoor temp of 70 at a
0 degree outdoor design temp.
What that means is: If my furnace is sized properly and my indoor
temperature is 70 and the outdoor temp is 0, then my furnace will run
24/7 until the outdoor temp begins to raise. If the outdoor temp
continues to drop to -10 or -20 below 0 then my house will begin to
get colder and colder and I will need to add some type of supplemental
heat.
On the other hand, with that same furnace, if it is 50 degrees outside
and 60 degrees in my home and I want to raise it to 70 I would
probably take much less than an hour.
What you are interested in is if the motor replacement you just got is
set properly. It should be set so that you get the proper "temperature
rise through your furnace as stated on the furnace equipment label.
Usually a temp in the range of 35 - 70 degrees.
More blower speed will lower this temp range. Less blower speed will
raise this temp range.
Bubba

Why would more blower speed lower this temp range? It seems to me that the
faster the air, the cooler the air blowing across elements/heat exchanger
will be, and the more heat *is getting transferred in.

Hey Zoot. Think of it this way:
Lets take a 100,000 btu furnace and pull the blower and motor out of
it. Now install a bathroom fart fan in its place. Turn it all on. What
happens? You get an extremely high temperature with almost no air
movement.
Now, lets take that same furnace and install a 4 foot wide 4 blade fan
with a 50 hp motor turning at 30,000 rpm. Now tell me how much heat
you feel on the outlet side of that furnace.
Answer: None
It all needs to be done within a range. Thats why motors have 3 and 4
blower speeds. Its so you can set the heating blower speed and cooling
blower speed to fall within a temperature rise or drop across the heat
exchanger or cooling coil.
Clear as mud now or are you one of those guys with an EE degree?
Bubba- Hide quoted text -

- Show quoted text -

At Zero, what do you do, offer coupons on your undersized crap.
Walmart elect heat !!!! Yea and you sell 95% efficent WH tanks you
moron, they dont EXIST, mr
Bubbatardcrapolaasbrainsimanimbicileretard, and more