Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg

On Jan 15, 3:20*am, Zen wrote:
Just as it gets cold, my Payne hot air propane-fired furnace broke!http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. *There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?http://www3.picturepush.com/photo/a/...g/11964131.jpg

Some observations:

I don't know how your furnace is designed or hooked up.
But I've never seen a forced air furnace where the blower
goes on for a minute BEFORE the furnace fires. Every
one I've ever seen works exactly the opposite. The
burner fires FIRST and then the blower comes on a
minute or so later. That avoids the furnace blowing cold
air. The blower is triggered either by a temperature
switch in the plenum or by a control board.

It's usually not a good idea to just start replacing
components randomly. Regarding the list of suspects:


1. The flame apparatus

what's that? the actual burner assembly?

2. The circuit board

3. The lockout switch

Which lockout switch? There typically are
several mechanisms involved. If it's a simple switch,
it can be bypassed for test purposes instead of just
replacing it on the theory it might be bad. And if it's
the switch on the blower compartment, in the furnaces
I've worked on, that switch only disabled the blower.
The fact that the blower works tells you that switch is
OK.

First area I'd be looking into is if the ignitor is
activating, ie is it trying to light at all? That's the first
step in the process and the ignitor going bad is one
frequent source of problems.

Sorry to hear your furnace went out. I'd suggest to call
your friends and relatives, and see who they hire for
furnace repair. Home furnace isn't a good place to learn
on. Too many things can go wrong.

Christopher A. Young
Learn more about Jesus
www.lds.org
..

"Zen" wrote in message ...
Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg

On Tue, 15 Jan 2013 08:20:03 +0000 (UTC), Zen wrote:

Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg


Don't waste money throwing parts at it.
Get the model number, then post this with model number to alt.hvac.
You might get troubleshooting procedures there.
If not, get the manual which should allow you to pinpoint the problem.
For parts, just google the model number.

On Jan 15, 5:33*am, "
wrote:
On Jan 15, 3:20*am, Zen wrote:









Just as it gets cold, my Payne hot air propane-fired furnace broke!http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. *There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?http://www3.picturepush.com/photo/a/...g/11964131.jpg

Some observations:

I don't know how your furnace is designed or hooked up.
But I've never seen a forced air furnace where the blower
goes on for a minute BEFORE the furnace fires. *Every
one I've ever seen works exactly the opposite. *The
burner fires FIRST and then the blower comes on a
minute or so later. *That avoids the furnace blowing cold
air. *The blower is triggered either by a temperature
switch in the plenum or by a control board.

It's usually not a good idea to just start replacing
components randomly. * Regarding the list of suspects:

1. The flame apparatus

what's that? *the actual burner assembly?

2. The circuit board

3. The lockout switch

Which lockout switch? *There typically are
several mechanisms involved. *If it's a simple switch,
it can be bypassed for test purposes instead of just
replacing it on the theory it might be bad. *And if it's
the switch on the blower compartment, in the furnaces
I've worked on, that switch only disabled the blower.
The fact that the blower works tells you that switch is
OK.

First area I'd be looking into is if the ignitor is
activating, ie is it trying to light at all? *That's the first
step in the process and the ignitor going bad is one
frequent source of problems.

I would have agreed with T4 on his commentary UNTIL I watched this
YouTube video.

http://www.youtube.com/watch?v=bEcJe60oQlk

seems like a blower (gas combustion related) comes on first, then the
unit fires up.

I guess my question is "which blower" does the OP refer to?

The YouTube search function aint great and this furnance isnt the OP's
make/ model but it might be helpful.

cheers
Bob

Vic Smith wrote:
Don't waste money throwing parts at it.
Get the model number, then post this with model number to alt.hvac.
You might get troubleshooting procedures there.
If not, get the manual which should allow you to pinpoint the problem.
For parts, just google the model number.

Are they still rude to do-it-yourself-ers over at alt.hvac as they used to be?

On Jan 15, 12:04*pm, DD_BobK wrote:
On Jan 15, 5:33*am, "
wrote:





On Jan 15, 3:20*am, Zen wrote:

Just as it gets cold, my Payne hot air propane-fired furnace broke!http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. *There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?http://www3.picturepush.com/photo/a/...g/11964131.jpg

Some observations:

I don't know how your furnace is designed or hooked up.
But I've never seen a forced air furnace where the blower
goes on for a minute BEFORE the furnace fires. *Every
one I've ever seen works exactly the opposite. *The
burner fires FIRST and then the blower comes on a
minute or so later. *That avoids the furnace blowing cold
air. *The blower is triggered either by a temperature
switch in the plenum or by a control board.

It's usually not a good idea to just start replacing
components randomly. * Regarding the list of suspects:

1. The flame apparatus

what's that? *the actual burner assembly?

2. The circuit board

3. The lockout switch

Which lockout switch? *There typically are
several mechanisms involved. *If it's a simple switch,
it can be bypassed for test purposes instead of just
replacing it on the theory it might be bad. *And if it's
the switch on the blower compartment, in the furnaces
I've worked on, that switch only disabled the blower.
The fact that the blower works tells you that switch is
OK.

First area I'd be looking into is if the ignitor is
activating, ie is it trying to light at all? *That's the first
step in the process and the ignitor going bad is one
frequent source of problems.

I would have agreed with T4 on his commentary UNTIL I watched this
YouTube video.

http://www.youtube.com/watch?v=bEcJe60oQlk

seems like a blower (gas combustion related) comes on first, then the
unit fires up.

I guess my question is "which blower" does the OP refer to?

The YouTube search function aint great and this furnance isnt the OP's
make/ model but it might be helpful.

cheers
Bob- Hide quoted text -

- Show quoted text -

The video clearly states that it's the "vent stack blower"
that's coming on. It's a newer, higher efficiency furnace.
The blower is actually called an inducer blower.

Since the OP said that the furnace blower blows cold
air and there is no evidence of an inducer blower in
the pic he supplied, I assume it's the air handler fan
that he's tallking about when he refers to the blower
a second time.

But, then George here gets all upset if one makes
what appear to be reasonable assumptions
when responding to a question. According to George,
I'm not supposed to answer, only ask for "clarification".

On 1/15/2013 12:20 AM, Zen wrote:
Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg

Probably a bad idea to just start replacing parts.

It's strange that the main blower starts up at all, because normally it
doesn't start until after the flame is detected by the flame sensor and
the burners start (so it doesn't blow cold air), unless you have the fan
always on at the thermostat.

The sequence should be:

1. Draft inducer fan starts up and closes switch (via suction) so the
controller knows that the draft inducer is operating and it's safe to
light the burner. You can check this with an ohm meter, or jumper across
it to test it (however it must be open when the furnace starts, then
closed after the draft inducer fan starts, you can't jumper it closed
before the draft inducer fan starts).

2. Glow plug heats up (or spark ignitor starts sparking). You can check
that a glow plug is getting power with a voltmeter (should be 24VAC) and
you can see it glow red. A spark ignitor should make a noise.

3. Gas valve opens and burners ignite. Audible thunk as the solenoid is
activated. Controller knows that the burners are lit by looking at the
flame sensor and will close the gas valve after a short time if there is
no flame. You can test the gas valve by turning off the gas to the
furnace, unplugging the wires to the valve, and connecting 24VAC or so
to the valve from a small transformer. If you hear a thunk then the
solenoid is activating and the gas valve is probably okay.

4. Main blower starts up.


If one of the flame-out sensors is bad (open) the gas valve won't turn
on. There are usually three or four flame-out sensors in series. If
there's a crack in the heat exchanger then flames can shoot out the
front of the furnace and the flame-out sensors will shut off the gas.


When my furnace broke a couple of months ago it was an intermittent gas
valve.

When my friend's furnace broke last month it was an intermittent draft
inducer fan switch (sometimes it's just a clogged suction hose, but this
time the switch was bad).

If it's an older furnace with relays on the controller board you can
hear the relays click as various things are activated. The draft inducer
fan relay will click, the ignitor relay will click, and the gas valve
relay will click.

On Jan 15, 12:50*pm, sms wrote:
On 1/15/2013 12:20 AM, Zen wrote:





Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. *There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg

Probably a bad idea to just start replacing parts.

It's strange that the main blower starts up at all, because normally it
doesn't start until after the flame is detected by the flame sensor and
the burners start (so it doesn't blow cold air), unless you have the fan
always on at the thermostat.

The sequence should be:

1. Draft inducer fan starts up and closes switch (via suction) so the
controller knows that the draft inducer is operating and it's safe to
light the burner. You can check this with an ohm meter, or jumper across
it to test it (however it must be open when the furnace starts, then
closed after the draft inducer fan starts, you can't jumper it closed
before the draft inducer fan starts).

Agree, IF it has an inducer. From the picture, there was no
evidence of one. It looks like an older furnace.



2. Glow plug heats up (or spark ignitor starts sparking). You can check
that a glow plug is getting power with a voltmeter (should be 24VAC) and
you can see it glow red. A spark ignitor should make a noise.

3. Gas valve opens and burners ignite. Audible thunk as the solenoid is
activated. Controller knows that the burners are lit by looking at the
flame sensor and will close the gas valve after a short time if there is
no flame. You can test the gas valve by turning off the gas to the
furnace, unplugging the wires to the valve, and connecting 24VAC or so
to the valve from a small transformer. If you hear a thunk then the
solenoid is activating and the gas valve is probably okay.

4. Main blower starts up.

Yes, usually after a delay of a minute or so




If one of the flame-out sensors is bad (open) the gas valve won't turn
on. There are usually three or four flame-out sensors in series. If
there's a crack in the heat exchanger then flames can shoot out the
front of the furnace and the flame-out sensors will shut off the gas.

When my furnace broke a couple of months ago it was an intermittent gas
valve.

When my friend's furnace broke last month it was an intermittent draft
inducer fan switch (sometimes it's just a clogged suction hose, but this
time the switch was bad).

If it's an older furnace with relays on the controller board you can
hear the relays click as various things are activated. The draft inducer
fan relay will click, the ignitor relay will click, and the gas valve
relay will click.- Hide quoted text -

- Show quoted text -

On 1/15/2013 9:04 AM, DD_BobK wrote:
On Jan 15, 5:33 am, "
wrote:
On Jan 15, 3:20 am, Zen wrote:









Just as it gets cold, my Payne hot air propane-fired furnace broke!http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?http://www3.picturepush.com/photo/a/...g/11964131.jpg

Some observations:

I don't know how your furnace is designed or hooked up.
But I've never seen a forced air furnace where the blower
goes on for a minute BEFORE the furnace fires. Every
one I've ever seen works exactly the opposite. The
burner fires FIRST and then the blower comes on a
minute or so later. That avoids the furnace blowing cold
air. The blower is triggered either by a temperature
switch in the plenum or by a control board.

It's usually not a good idea to just start replacing
components randomly. Regarding the list of suspects:

1. The flame apparatus

what's that? the actual burner assembly?

2. The circuit board

3. The lockout switch

Which lockout switch? There typically are
several mechanisms involved. If it's a simple switch,
it can be bypassed for test purposes instead of just
replacing it on the theory it might be bad. And if it's
the switch on the blower compartment, in the furnaces
I've worked on, that switch only disabled the blower.
The fact that the blower works tells you that switch is
OK.

First area I'd be looking into is if the ignitor is
activating, ie is it trying to light at all? That's the first
step in the process and the ignitor going bad is one
frequent source of problems.

I would have agreed with T4 on his commentary UNTIL I watched this
YouTube video.

http://www.youtube.com/watch?v=bEcJe60oQlk

seems like a blower (gas combustion related) comes on first, then the
unit fires up.

That's the draft inducer fan. The furnace won't start at all unless that
fan is running. There's a tube going to a suction activated switch that
indicates that the draft inducer fan is running. My friend's furnace had
an intermittent draft inducer switch and sometimes would not start at
all, sometimes would start and run for a while then stop.

I suspect that the reason that the main blower is running is that the OP
has it turned on at the thermostat, i.e. "Fan On" instead of "Auto."

On Tue, 15 Jan 2013 09:04:58 -0800, "Bob F"
wrote:

Vic Smith wrote:
Don't waste money throwing parts at it.
Get the model number, then post this with model number to alt.hvac.
You might get troubleshooting procedures there.
If not, get the manual which should allow you to pinpoint the problem.
For parts, just google the model number.

Are they still rude to do-it-yourself-ers over at alt.hvac as they used to be?


Don't know. It was just a suggestion. There are internet forums too.
This seems generally polite to DIY'ers.
http://ths.gardenweb.com/forums/hvac/
My main point was to DIY you should have model number and/or a manual
as your starting point.

On Jan 15, 12:03*pm, Vic Smith
wrote:
On Tue, 15 Jan 2013 09:04:58 -0800, "Bob F"
wrote:

Vic Smith wrote:
Don't waste money throwing parts at it.
Get the model number, then post this with model number to alt.hvac.
You might get troubleshooting procedures there.
If not, get the manual which should allow you to pinpoint the problem.
For parts, just google the model number.

Are they still rude to do-it-yourself-ers over at alt.hvac as they used to be?

Don't know. *It was just a suggestion. *There are internet forums too..
This seems generally polite to DIY'ers.http://ths.gardenweb.com/forums/hvac/
My main point was to DIY you should have model number and/or a manual
as your starting point.

Are you sure the unit is not in the air-conditioning mode?????

On 1/15/2013 9:55 AM, wrote:
On Jan 15, 12:50 pm, sms wrote:
On 1/15/2013 12:20 AM, Zen wrote:





Just as it gets cold, my Payne hot air propane-fired furnace broke!
http://www4.picturepush.com/photo/a/...g/11964117.jpg

All of a sudden, the blower just blows cold air constantly without letup.
The pilot flame never starts.
Obviously, the gas never lights up either.

This happened, all of a sudden.

Normally, it has an electronic pilot, which lights the gas about a minute
after the blower starts. There is plenty of propane.

Any troubleshooting ideas?

I think there are three main components:
1. The flame apparatus
2. The circuit board
3. The lockout switch

I'm inclined to just buy all three, and replace (and have a spare), since
I remember the last service call was expensive and the circuit board was
replaced in seconds after a three week wait for the parts to arrive.

Do you have any idea WHERE I can get the three main components?
http://www3.picturepush.com/photo/a/...g/11964131.jpg

Probably a bad idea to just start replacing parts.

It's strange that the main blower starts up at all, because normally it
doesn't start until after the flame is detected by the flame sensor and
the burners start (so it doesn't blow cold air), unless you have the fan
always on at the thermostat.

The sequence should be:

1. Draft inducer fan starts up and closes switch (via suction) so the
controller knows that the draft inducer is operating and it's safe to
light the burner. You can check this with an ohm meter, or jumper across
it to test it (however it must be open when the furnace starts, then
closed after the draft inducer fan starts, you can't jumper it closed
before the draft inducer fan starts).

Agree, IF it has an inducer. From the picture, there was no
evidence of one. It looks like an older furnace.

It was an incomplete photo, but you're right, I did not see the
draft-inducer fan. My furnace is pretty old and it has one.

This is what I wrote up when I was troubleshooting my furnace (additions
and corrections are welcome):

When temperature falls below thermostat setting, the thermostat connects
the R (or Rh) wire to the W wire. If the furnace doesn't do anything,
try jumpering the R or Rh contact to the W contact. If the furnace
starts, then you have a bad thermostat.

The furnace controller board goes through a sequence of steps to ensure
all safety systems are working.

Draft inducer fan and pressure sensing switch
---------------------------------------------------------------
The small draft inducer fan (not the main blower) is connected to the
pressure sensing switch by a piece of tubing. This fan gets the exhaust
air moving up through the chimney.

The controller will check that the pressure sensing switch is open,
prior to turning on the draft inducer fan. If the pressure sensing
switch is closed even when the draft inducer fan isn't running then the
pressure sensing switch probably failed in the closed position (very rare).

If the pressure sensing switch is open then the controller will turn on
the draft inducer fan, wait a few seconds, then check to see that the
pressure sensing switch has closed. If the pressure sensing switch did
not close then the controller will not even attempt to activate the
pilot ignitor or open the gas valve.

Flame Sensor
--------------------
This can be a temperature or optical sensor. The controller will check
that the sensor does not indicate the presence of a flame (to ensure
that the sensor has not failed) then it will activate the ignitor (spark
or glow plug) unless your furnace uses a pilot light that is always on.
You may be able to hear a click as the relay on the controller board
closes and the ignitor turns on.

Gas Valve
--------------
A few seconds after activating the ignitor (glow plug), the controller
will open the gas valve. For a piezeo ignitor the gas valve may open
simultaneously with the piezeo ignitor sparking. You may be anle to hear
a click on the controller board when the gas valve relay closes. The gas
valve uses a 24VAC solenoid to open the valve. There will be an audible
thunk when the valve opens. If you have a volt meter, you can set it to
AC volts and check that the 24V is being applied to the gas valve.

The burners will ignite, and the flame sensor will indicate the presence
of flame. If the burners don't ignite then the controller will
de-energize the gas valve (closing the gas valve, assuming it was
working and opened).

If the gas valve solenoid fails then the gas valve will not open, or it
will open sometimes but close before the temperature reaches the
thermostat setting. Often a gas valve fails intermittently and is
temperature sensitive.

So the sequence for the controller:

1. Checks that the flame sensor is open (looks at the voltage) so it
knows that it hasn't failed in the closed (flame present) position.

2. Checks that the flame-out sensors are closed so it knows that they
haven't failed in the open (no flame out) position.

3. Checks that the pressure sensing switch is open so it knows that it
hasn't failed in the closed (fan running) position.

4. Turns on draft inducer fan (should hear small fan power on). If it
doesn't power on you can check the voltage on the terminals of the fan
to determine if the fan is getting power so you know if the fan is bad
or the controller is not turning it on.

5. Verifies that the draft inducer fan is working by checking that the
pressure sensing switch (connected by a thin hose to the fan) has closed.

6. Activates ignitor (spark or glow plug) (should hear a relay on the
control board close).

6a. For glow plug, waits a few seconds for it to heat up.

7. Opens gas valve. You will hear a thunk as the solenoid pulls the
valve open. The burners should immediately ignite.

8. Waits a few seconds then checks that flame sensor indicates heat is
present.

9. Waits a while then turns on blower fan


Troubleshooting is a process of elimination.
------------------------------------------------------------
1. Thermostat. Jumper the R or Rh contact to the W contact. If the
furnace starts, then you have a bad thermostat.

2. Pressure sensing switch. When the furnace is off, check that the
switch is open with an VOM (volt ohm meter).

3. Draft inducer fan. If you don't hear it starting then check to see
that the fan is getting power from the controller. If it's getting power
but not starting then the fan has failed.

4. Pressure sensing switch. If the draft inducer fan starts but the
ignitor never is activated then try jumpering across the contacts of the
pressure sensing switch. If everything starts working then the pressure
sensing switch is bad or perhaps the hose to it is clogged.

5. Ignitor. For a glow plug you will see it glow bright red, and for a
piezeo ignitor you will see and hear sparks. If the ignitor is working
but the burners don't light then the gas valve is not opening and is
likely bad because the controller would not turn on the ignitor if one
of the other safety devices was tripped.

6. Gas valve. Check the voltage on the terminals of the valve. You
should see around 24VAC. When the controller puts the 24VAC onto the gas
valve terminals you will hear a relay on the control board click and you
will hear the solenoid on the gas valve thunk.

7. If the burners light but go out before the house reaches the
temperature set on the thermostat then the gas valve is probably working
intermittently, or one of the safety devices is intermittent. The
pressure sensing switch can be intermittent and perhaps the flame sensor
as well (though unlikely that the flame sensor is intermittent).

8. With the gas off, you can test the gas valve by removing the wires
from the controller and applying 21 to 24VAC to the terminals (use a
transformer such as that for a doorbell or sprinkler valves). If you
hear a very audible thunk then the valve is opening. If you hear nothing
then the valve is probably bad. However the valve could still be bad
even if you hear the thunk because they tend to fail intermittently.

I went back and looked at the photos. That design is totally obvious to me,
it's a gravity draft 70 percenter.

Christopher A. Young
Learn more about Jesus
www.lds.org
..

"SMS" wrote in message
...
On 1/15/2013 2:46 PM, wrote:
On Jan 15, 5:42 pm, "Stormin Mormon"
wrote:
If you look at the pictures OP provided, you
can see how many blowers the furnace has,
and what their function are.

http://www4.picturepush.com/photo/a/...g/11964117.jpg
http://www3.picturepush.com/photo/a/...g/11964131.jpg

Christopher A. Young
Learn more about Jesus
www.lds.org


By my count there is only one blower, the one that serves
as the air handler. Yes?

Can't tell because the draft inducer fan is normally high up, above
where the photo stops.

On Jan 15, 2:46*pm, "
wrote:
On Jan 15, 5:42*pm, "Stormin Mormon"

wrote:
If *you look at the pictures OP provided, you
can see how many blowers the furnace has,
and what their function are.

* * *http://www4.picturepush.com/photo/a/...g/11964117.jpg
* * *http://www3.picturepush.com/photo/a/...g/11964131.jpg

Christopher A. Young
Learn more about Jesus
*www.lds.org

By my count there is only one blower, the one that serves
as the air handler. *Yes?

Yes...seems reasonable. Unit looks old probably only one fan

On Jan 15, 10:29*pm, "Stormin Mormon"
wrote:
I went back and looked at the photos. That design is totally obvious to me,
it's a gravity draft 70 percenter.

Christopher A. Young
Learn more about Jesus
*www.lds.org
.


+1
That's sure what it looked exactly like to me. But
I have to be careful now. George says it's not OK to
try to decipher what a poster actually has based on
what he gives us. I'm supposed to only ask clarifying
questions, otherwise the thread becomes too long as
we try to sort it out.

That's for sure, we have to do what George says.

Wonder if the OP ever got the heat back on? And,
if he got permission from George to have it fixed?

Christopher A. Young
Learn more about Jesus
www.lds.org
..

wrote in message
...

But I have to be careful now. George says it's not OK to
try to decipher what a poster actually has based on
what he gives us. I'm supposed to only ask clarifying
questions, otherwise the thread becomes too long as
we try to sort it out.