On 12/10/2013 06:38 PM, Danny D'Amico wrote:
On Tue, 10 Dec 2013 18:10:46 -0600, philo wrote:

If the blower is working that means the furnace is getting power.
Unless you know /exactly/ what you are doing, a furnace is one thing
you should not fool with.

The fact that I assume 120 volts (and whatever the high-tension leads
have in them) is there, is the key reason why I'm not just jumping
leads just yet.

I want to *measure* first. That's not dangerous. Jumping things is
much more dangerous (if I make a mistake).

So, at the moment, I concentrated first on identifying all the parts
of the furnace (which I snapped a picture of and posted separately).

Then, I am concentrating on figuring out how those parts play together.

After that, I'll do the measuring.

And then the jumping.

I'm sorry I'm probably way slower than you guys would like, but, I'm
trying to actually understand the darn thing first ... Thanks for
your patience. I've still got to read that Carrier manual ...





Start with the basics:


1) You have determined that the furnace has power. That's good.

2) Turn the thermostat down below the temperature of the house...
Have an assistant stand by the thermostat and now go to the furnace.
When you are there have them turn the thermostat up.


Does anything at all happen?

Of so...describe what it is doing and post back.


If *absolutely* nothing happens, then a wire on the thermostat could be
broken.


If you hear a click and gas starts to flow, but nothing ignites, then it
shuts down...then the igniter is bad.

philo wrote:
On 12/10/2013 06:38 PM, Danny D'Amico wrote:
On Tue, 10 Dec 2013 18:10:46 -0600, philo wrote:

If the blower is working that means the furnace is getting power.
Unless you know /exactly/ what you are doing, a furnace is one thing
you should not fool with.

The fact that I assume 120 volts (and whatever the high-tension leads
have in them) is there, is the key reason why I'm not just jumping
leads just yet.

I want to *measure* first. That's not dangerous. Jumping things is
much more dangerous (if I make a mistake).

So, at the moment, I concentrated first on identifying all the parts
of the furnace (which I snapped a picture of and posted separately).

Then, I am concentrating on figuring out how those parts play together.

After that, I'll do the measuring.

And then the jumping.

I'm sorry I'm probably way slower than you guys would like, but, I'm
trying to actually understand the darn thing first ... Thanks for
your patience. I've still got to read that Carrier manual ...





Start with the basics:


1) You have determined that the furnace has power. That's good.

2) Turn the thermostat down below the temperature of the house...
Have an assistant stand by the thermostat and now go to the furnace.
When you are there have them turn the thermostat up.


Does anything at all happen?

Of so...describe what it is doing and post back.


If *absolutely* nothing happens, then a wire on the thermostat could be
broken.


If you hear a click and gas starts to flow, but nothing ignites, then it
shuts down...then the igniter is bad.
Hi,
Then there is no reason blower would run. Just jumper W and C at the
furnace after taping down the cover interlock switch. If furnace works
go to 'stat and do the ssame. If furnace does not start then can assue
wire is broken or loose some where.

.... is the furnace even on?

"Tony Hwang" wrote in message ...

Hi,
Then there is no reason blower would run. Just jumper W and C at the
furnace after taping down the cover interlock switch. If furnace works
go to 'stat and do the ssame. If furnace does not start then can assue
wire is broken or loose some where.

He already determined that the blower came on. Now, we need to determine
why. That is why I asked for him to get the t-stat set up to all off, then
have the cover replaced. If the blower turns back on something is making
an improper contact, one of the relays is stuck, or the HTR relay is not
functional (bad coil). That is if he is correct when he stated that he had
a nominal control voltage. 27vac, I believe.

Be careful asking him to play with the access door switch. That switch has
120V going to it. Sometimes they are not finger proof. :-)

On Tuesday, December 10, 2013 7:26:39 PM UTC-5, Danny D'Amico wrote:
On Tue, 10 Dec 2013 15:08:26 -0800, wrote:



Turn furnace switch off.



There is no furnace switch, that I know of.

May be different in your part of the world and I'm not
sure what that code actually says. But every furnace I've
ever seen there has been at least one emergency switch with
a red plate. Sometimes it's in the basement stairwell,
with the furnace in the basement.




The wires come directly into the furnace from the outside.

Of course, I can shut off a breaker ...



Connect the red wire to the white wire.

Turn the furnace switch back on.



OK. I have the breakers off. I'll wait a few minutes now.



From another post, before I ruin something, is this correct?

a. Connecting red to white should fire the furnace

b. Connecting red to green should turn the blower on



Is this where I should make those jumper connections?

http://farm3.staticflickr.com/2849/1...e7793ca9_o.gif



Yes, you can jumper from the red to the white on the
right side, the R and WH terminals.








BTW, normally I *measure* stuff (voltages usually) before jumping

from one point to another; but I would need to know what *two*

points to measure. Based on Stormin' Mormon's prior post, I'll read:



A. Red to White (AC voltage) ... is this what I should read?

B. Red to Green (AC voltage) ... is this what I should read?



NOTE: I haven't finished reading everything, so, if I'm repeating,

I apologize.



It's unlikely it's the thermostat to begin with, so why waste time

on all kinds of tests when there is a simple and very direct method?



I've buttoned up the thermostat. It just took me a while to report

back because I was trying to figure out how the darn furnace works

and what the parts were...

If you hadn't put it back together, you could have just connected
the red and white together there.

On Tue, 10 Dec 2013 15:15:00 -0800, wrote:

Did it come off at some point in the
diagnostic process or was it off to begin with and the cause
of the whole problem?

IIRC, I took it off months ago, when it was something like 95 degrees
outside, but all I could do was stare at the setup as I didn't
understand how to troubleshoot.

But, not having A/C in 95 degree weather is nothing like not having
heat in 32 degree weather; so, it's more important to figure it out
now than in the summer.

I'm ok, by the way; but the wife and kids don't like the cold.

On Tue, 10 Dec 2013 16:12:10 -0500, David L. Martel wrote:

Confirm that you have gas.

The stove and hot water heater are burning fine, and the
propane tank is nearly full; and the valve is in the "on"
position; so, I can pretty much assume I have gas.

wrote in message ...
On Tuesday, December 10, 2013 7:26:39 PM UTC-5, Danny D'Amico wrote:
On Tue, 10 Dec 2013 15:08:26 -0800, wrote:



Turn furnace switch off.



There is no furnace switch, that I know of.

May be different in your part of the world and I'm not
sure what that code actually says. But every furnace I've
ever seen there has been at least one emergency switch with
a red plate. Sometimes it's in the basement stairwell,
with the furnace in the basement.

Some units will use a cord plugged into a receptacle. Usually
this is only for control voltage, but in his case the control
power supply also powers the blower. He might have a disconnect
that he has not noticed. Usually this is required, but if in
eyesight of the panel I don't think it is in this case.

"Danny D'Amico" wrote in message
news
On Tue, 10 Dec 2013 18:10:46 -0600, philo wrote:

If the blower is working that means the furnace is getting power.
Unless you know /exactly/ what you are doing, a furnace is one thing
you should not fool with.

The fact that I assume 120 volts (and whatever the high-tension leads
have in them) is there, is the key reason why I'm not just jumping
leads just yet.

I want to *measure* first. That's not dangerous. Jumping things is
much more dangerous (if I make a mistake).

So, at the moment, I concentrated first on identifying all the parts
of the furnace (which I snapped a picture of and posted separately).

Then, I am concentrating on figuring out how those parts play together.

After that, I'll do the measuring.

And then the jumping.

I'm sorry I'm probably way slower than you guys would like, but, I'm
trying to actually understand the darn thing first ... Thanks for
your patience. I've still got to read that Carrier manual ...


Check for 24VAC between SEC1 and SEC 2. If there is no 24VAC, check the
transformer solder joints on the circuit board

Leave one lead on SEC2 and check for 24VAC on the red wire terminal. If you
have 24VAC the interlocks are OK. If not, trace back until the open
interlock is found

With the stat calling for heat, check for 24VAC at the W terminal. If you
have 24VAC, the stat heat circuit is good. You should hear the gas valve
click and the igniter spark.

If you look at the schematic for 394JA you will see the blower motor relay
is normally closed. If the furnace is powered up and there is not 24VAC at
the R terminal, the blower motor will run right away and not shut off, which
is what you said it's doing (note the jumper between R and GH)

On Tue, 10 Dec 2013 18:00:40 -0800, wrote:

May be different in your part of the world and I'm not
sure what that code actually says. But every furnace I've
ever seen there has been at least one emergency switch with
a red plate. Sometimes it's in the basement stairwell,
with the furnace in the basement.

The California-specific PDF that I was sent says what you say,
in that a switch must be within sight of the furnace; but it
also allows for the door switch serving double duty as that shutoff.

Literally, that PDF says: "a disconnecting means must be located
within sight of, and readily accessible to, the furnace. The blower
door switch may be acceptable in some areas as a disconnecting means".

So, from that, I must assume the blower door switch is *my*
disconnecting means. I'll snap a photo of the electrical wires
tomorrow (in the daylight) to show you what mine looks like.

On Tue, 10 Dec 2013 18:00:40 -0800, wrote:

Is this where I should make those jumper connections?
http://farm3.staticflickr.com/2849/1...e7793ca9_o.gif

Yes, you can jumper from the red to the white on the
right side, the R and WH terminals.

This is good to know because there are *two* red and white sets of wires!
So, I'll jump the right set of red and white wires only.

On Tue, 10 Dec 2013 18:00:40 -0800, wrote:

If you hadn't put it back together, you could have just connected
the red and white together there.

I see now that the red (which is 24 volt power), is "connected" to
the white (which is the indication of the call for heat).

In summary:
1. Red wire is 24VAC hot.
2. Thermostat "calls for heat" by connecting Red to White.
3. Thermostat "calls for fan" by connecting Red to Green.

So, if I manually made those connections, it would bypass the thermostat.

(I didn't know this at all, earlier today ... so I'm just repeating what
I learned today).

On Tue, 10 Dec 2013 20:54:12 -0600, Irreverent Maximus wrote:

Some units will use a cord plugged into a receptacle. Usually
this is only for control voltage, but in his case the control
power supply also powers the blower. He might have a disconnect
that he has not noticed. Usually this is required, but if in
eyesight of the panel I don't think it is in this case.

I'll look again tomorrow, by following the power wires, to see
where they go - and if there is a shutoff switch that I didn't
see yet.

It's dark and cold downstairs now, so I'll wait for daylight where
I can snap better pictures for you.

"Danny D'Amico" wrote in message
news
On Tue, 10 Dec 2013 17:02:14 -0500, Stormin Mormon wrote:

I tried download the PDF, but the file came through
corrupted.

I googled for the name of the document that Carrier sent me:
40394dp65-a.pdf

This directory came up; which contains a *lot* of furnace PDFs:
http://www.xpedio.carrier.com/idc/gr...ments/techlit/

This one looks to be similar (it's for the 394J where mine is 394JAW):
http://xpedio.carrier.com/idc/groups...0394dp65-a.pdf

This one has an even closer model number (394JAZ where mine is 394JAW):
http://xpedio.carrier.com/idc/groups...i394j-30-1.pdf


The schematic should be attached to the inside of one of the covers on the
furnace.....

On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

http://www.xpedio.carrier.com/idc/gr...0394dp65-a.pdf
download above link. If it is corrupted, update your PDF reader.

I read the entire PDF, from front to back.
Here's a summary of what I gleaned about the furnace operation:

Summary:
1. Red wire is 24VAC hot.
2. Thermostat "calls for heat" by connecting Red to White.
3. Thermostat "calls for fan" by connecting Red to Green.

Details:
Thermostat "calls for heating" by connecting Red to White.

Power then goes from the Transformer - Fusible Link - Limit Switch -
Vent Safety Shut-off Switch - pilot (both "pick" & "hold" gas valves)
such that pilot gas flows, where it ignites.

~60 seconds after pilot, safety pilot switches its contacts and energizes
the main valve portion of the gas valve, where, about 10 seconds later,
the main gas valve opens, and the main gas is ignited by the pilot flame.

~75 seconds after the pilot lights, the fan control board activates the
fan on low speed (it uses the low speed for heating purposes).

When the thermostat "is satisfied", the connection between R & W is broken.
Gas is immediately stopped to both the pilot and main burners.
The blower continues for about 100 seconds.

If the furnace overheats, the Limit Switch opens.
If the furnace overheats in the vestibule, the Fusible Link opens.
If the furnace overheats in the vents, the Vent Safety Switch opens.

I see the fusible link on the red wire he
http://farm8.staticflickr.com/7323/1...56224304_o.gif

I'm guessing this is the limit switch:
http://farm3.staticflickr.com/2814/1...0de1c8bd_o.gif

But, I can't seem to find the "Vent Safety Switch".

On 12/10/2013 6:54 PM, Danny D'Amico wrote:

So now that I've identified "most" of the parts (I'm not sure what
the purpose of the lockout timer and that sensor thing are), it's
time for me to figure out what/how to test and debug the thing...

IIRC, your manual mentioned spark ignitor. I think
you're having fun, but you really need to call
the man.


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

On 12/10/2013 7:54 PM, Danny D'Amico wrote:
On Tue, 10 Dec 2013 20:54:12 -0600, Irreverent Maximus wrote:

Some units will use a cord plugged into a receptacle. Usually
this is only for control voltage, but in his case the control
power supply also powers the blower.

The electrical code in the US demands that the furnace have
a permanent connection to the power source...no plugs allowed.
But when I asked the electrical inspector if I could put a plug
on it so I could run it from a generator, he said, "no problem".
The electrical code is very strict...except when it isn't.


He might have a disconnect
that he has not noticed. Usually this is required, but if in
eyesight of the panel I don't think it is in this case.

I'll look again tomorrow, by following the power wires, to see
where they go - and if there is a shutoff switch that I didn't
see yet.

It's dark and cold downstairs now, so I'll wait for daylight where
I can snap better pictures for you.

"Rick" wrote in message
...

"Danny D'Amico" wrote in message
news
On Tue, 10 Dec 2013 18:10:46 -0600, philo wrote:

If the blower is working that means the furnace is getting power.
Unless you know /exactly/ what you are doing, a furnace is one thing
you should not fool with.

The fact that I assume 120 volts (and whatever the high-tension leads
have in them) is there, is the key reason why I'm not just jumping
leads just yet.

I want to *measure* first. That's not dangerous. Jumping things is
much more dangerous (if I make a mistake).

So, at the moment, I concentrated first on identifying all the parts
of the furnace (which I snapped a picture of and posted separately).

Then, I am concentrating on figuring out how those parts play together.

After that, I'll do the measuring.

And then the jumping.

I'm sorry I'm probably way slower than you guys would like, but, I'm
trying to actually understand the darn thing first ... Thanks for
your patience. I've still got to read that Carrier manual ...


Check for 24VAC between SEC1 and SEC 2. If there is no 24VAC, check the
transformer solder joints on the circuit board

Leave one lead on SEC2 and check for 24VAC on the red wire terminal. If
you have 24VAC the interlocks are OK. If not, trace back until the open
interlock is found

With the stat calling for heat, check for 24VAC at the W terminal. If you
have 24VAC, the stat heat circuit is good. You should hear the gas valve
click and the igniter spark.

If you look at the schematic for 394JA you will see the blower motor relay
is normally closed. If the furnace is powered up and there is not 24VAC at
the R terminal, the blower motor will run right away and not shut off,
which is what you said it's doing (note the jumper between R and GH)



Continue to trace the 24VAC as needed through the ignition lock out module
and safety pilot to find the faulty part

Irreverent Maximus wrote:

"Tony Hwang" wrote in message
...

Hi,
Then there is no reason blower would run. Just jumper W and C at the
furnace after taping down the cover interlock switch. If furnace works
go to 'stat and do the ssame. If furnace does not start then can assue
wire is broken or loose some where.

He already determined that the blower came on. Now, we need to determine
why. That is why I asked for him to get the t-stat set up to all off, then
have the cover replaced. If the blower turns back on something is making
an improper contact, one of the relays is stuck, or the HTR relay is not
functional (bad coil). That is if he is correct when he stated that he had
a nominal control voltage. 27vac, I believe.

Be careful asking him to play with the access door switch. That switch has
120V going to it. Sometimes they are not finger proof. :-)


Hi,
I already mentioned about that too. Maybe he can read but can't
comprehend? Getting zapped will make him call for pro help. It is hard
to get killed by 120V AC unless one's feet are bare and wet. If he is
afraid, some one has to be nearby to watch, ready to throw the breaker
in case he is getting zapped. Desire to learn is good thing but one has
to have some basic knowledge first. He can enroll at community college
to take electricity 101 or some thing like that. Oh, no, then he'll be
more dangerous knowing little bit......

On 12/10/2013 7:00 PM, Danny D'Amico wrote:

Besides, someone said I can jump whatever needs to be
jumped from down there anyway. Right?
http://farm3.staticflickr.com/2849/1...e7793ca9_o.gif


Oh, heck. The most expensive appliance in your
house, and you're crossing wires cause "someone"
said?

I think common sense is lacking, here.

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

On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

1st: Remove furnace access door (effectively cuts off control power).
2nd: Put thermostat back together making sure that all switches are in
the -off- position, and turn the temperature select to its lowest
setting.
3rd: Replace furnace door.
Does the blower immediately turn on still?

Nope. Now the blower doesn't go on at all when I hold down the furnace door
switch. I did hear some snapping at one point, but then it went away.
It was like a sharp click click click...

So I opened the blower door (to interrupt the power) and gently tapped on
everything, especially the solenoids; and I wiggled all the wires. I found
one that seemed loose; and now it's back on tightly...

"Danny D'Amico" wrote in message
news
On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

1st: Remove furnace access door (effectively cuts off control power).
2nd: Put thermostat back together making sure that all switches are in
the -off- position, and turn the temperature select to its lowest
setting.
3rd: Replace furnace door.
Does the blower immediately turn on still?

Nope. Now the blower doesn't go on at all when I hold down the furnace
door
switch. I did hear some snapping at one point, but then it went away.
It was like a sharp click click click...


That's the igniter...



So I opened the blower door (to interrupt the power) and gently tapped on
everything, especially the solenoids; and I wiggled all the wires. I found
one that seemed loose; and now it's back on tightly...

"Stormin Mormon" wrote in message
...
On 12/10/2013 6:54 PM, Danny D'Amico wrote:

So now that I've identified "most" of the parts (I'm not sure what
the purpose of the lockout timer and that sensor thing are), it's
time for me to figure out what/how to test and debug the thing...

IIRC, your manual mentioned spark ignitor. I think
you're having fun, but you really need to call
the man.


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


Wonder if he's related to Stryped..... .

On 12/10/2013 10:00 PM, Danny D'Amico wrote:
On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

http://www.xpedio.carrier.com/idc/gr...0394dp65-a.pdf
download above link. If it is corrupted, update your PDF reader.

I read the entire PDF, from front to back.
Here's a summary of what I gleaned about the furnace operation:

Summary:
1. Red wire is 24VAC hot.
2. Thermostat "calls for heat" by connecting Red to White.
3. Thermostat "calls for fan" by connecting Red to Green.

Details:
Thermostat "calls for heating" by connecting Red to White.

Power then goes from the Transformer - Fusible Link - Limit Switch -
Vent Safety Shut-off Switch - pilot (both "pick" & "hold" gas valves)
such that pilot gas flows, where it ignites.

~60 seconds after pilot, safety pilot switches its contacts and energizes
the main valve portion of the gas valve, where, about 10 seconds later,
the main gas valve opens, and the main gas is ignited by the pilot flame.

~75 seconds after the pilot lights, the fan control board activates the
fan on low speed (it uses the low speed for heating purposes).

When the thermostat "is satisfied", the connection between R & W is broken.
Gas is immediately stopped to both the pilot and main burners.
The blower continues for about 100 seconds.

If the furnace overheats, the Limit Switch opens.
If the furnace overheats in the vestibule, the Fusible Link opens.
If the furnace overheats in the vents, the Vent Safety Switch opens.

I see the fusible link on the red wire he
http://farm8.staticflickr.com/7323/1...56224304_o.gif

I'm guessing this is the limit switch:
http://farm3.staticflickr.com/2814/1...0de1c8bd_o.gif

But, I can't seem to find the "Vent Safety Switch".


Yep, that's a limit but look to see if there's a little push button
reset between the 1/4" Faston terminals where the wires plug on to the
switch. Some of them have a manual reset that will click when it is
pushed in to reset it. ^_^

TDD

On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

Does the blower immediately turn on still?
If no: Switch thermostat to -heat- and set to highest temperature. Go
back to the furnace and listen. The blower should be running and
in a minute, or so, the burner should kick on. This unit might have
a delay for the blower, so wait 2 minutes before deciding that things
are not functioning. That is it for this part until you come back
with an answer.
If Yes: Either the heating or the cooling relay is sticking. Once again, get
back with an answer.

Wow. I tried this just now, in the dark, and, for a short while, everything was
working again!

The click click click I had heard was a snapping sound as the pilot was being
lighted. Soon, the pilot light lit!
http://farm3.staticflickr.com/2845/1...8bf71569_o.gif

Then, after about a minute (I didn't measure it), the entire burner was aflame!
http://farm8.staticflickr.com/7397/1...80c6d243_o.gif

And, within another while (again, I didn't think to measure), the blower ran!
http://farm8.staticflickr.com/7427/1...ceb36cd5_o.gif

I accidentally hit the door switch while I was trying to measure voltages,
so the whole thing shut down - and I couldn't reproduce the success - but -
I'll try again tomorrow when I have more light to work with (and it will
be warmer besides, as it's going to be at freezing tonight).

On Tue, 10 Dec 2013 23:02:31 -0500, Stormin Mormon wrote:

Oh, heck. The most expensive appliance in your
house, and you're crossing wires cause "someone"
said?

I haven't actually "jumped" any wires yet, mainly for that reason
(that I don't know what I'm doing yet).

I *did* read the entire PDF sent to me by the Carrier company,
which explained how the system works by connecting "red" 24VAC
power to Red to "call for heating".

It was interesting that the fan (green wire) is actually controlled
by the furnace fan-control PCB board. Apparently the green on the
thermostat merely sets whether the fan is always on or whether it's
controlled by the furnace PCB board.

And, it was interesting that the fan speed is typically set to low
for heating and to high for air conditioning.

I also learned the size of my system is "036065", which means it's
80,000 BTU/hour for heating and 1220CFM for cooling.

Is that a pretty normal home heating and cooling system?

On Tue, 10 Dec 2013 23:05:40 -0500, Rick wrote:

I did hear some snapping at one point, but then it went away.
It was like a sharp click click click...

That's the igniter...

Ah. That must be this thing:
http://farm6.staticflickr.com/5493/1...04b85a9f_o.gif

The funny thing is that the PDF didn't say what caused the igniter to
start snapping. I guess I'll read the PDF again ...

Ah ... found it... It must be the thing called the "pilot igniter".

Here's what the PDF says about it:
"When the thermostat calls for heat, the control circuit is closed
between the terminals R and W. Power from transformer TRAN through
fusible link FL, limit switch LS, and vent safety shut-off switch
VSSS, energizes the pilot valve part of automatic gas valve GV and
*pilot igniter PI*. The pilot valve opens, permitting gas flow to the
pilot burner where it is ignited.

So, I guess that snapping was from the "pilot igniter".

On Tue, 10 Dec 2013 22:57:30 -0500, Rick wrote:

The schematic should be attached to the inside of one of the covers on the
furnace.....

It is. There are actually *two schematics* on that inside cover.

I'm not sure how this lockout timer module works; but it might be the culprit:
http://farm6.staticflickr.com/5518/1...27d0a8ef_o.gif

Otherwise, this is the schematic:
http://farm3.staticflickr.com/2863/1...ef8ce342_o.gif

On Tue, 10 Dec 2013 16:12:10 -0500, David L. Martel wrote:

Read section IV of the manual.
It explains what should occur and when in the heating process.

Here's my summary of the PDF, after reading it a couple of times:

1. Red wire is 24VAC hot.
2. Thermostat "calls for heat" by connecting Red to White.
3. Thermostat "calls for fan" by connecting Red to Green; but the
fan is actually controlled by the fan PCB so the thermostat only
tells the fan PCB if it's to run continuously or automatically.

Details:
Thermostat "calls for heating" by connecting Red to White.

Power goes from the 24VAC Transformer - Fusible Link - Limit Switch -
Vent safety shut-off switch - pilot ("pick" & "hold" gas valves)
such that pilot gas flows.

Power also flows to the igniter, which ignites the pilot flame.

60 seconds after pilot, safety pilot switches its contacts and energizes
the main valve portion of the gas valve, where, about 10 seconds later,
the main gas valve opens, and the gas is ignited by the pilot flame.

75 seconds after pilot, the fan control board activates the fan on low
speed.

When the thermostat "is satisfied", the connection between R & W is broken.
Gas is immediately stopped to both the pilot and main burners.
The blower continues for about 100 seconds.

If the furnace overheats, the Limit Switch opens.
http://farm3.staticflickr.com/2814/1...0de1c8bd_o.gif
If the furnace overheats in the vestibule, the Fusible Link opens.
http://farm8.staticflickr.com/7323/1...56224304_o.gif
If the furnace overheats in the vents, the Vent Safety Switch opens.
(I have not found this VSSS yet.)
There is also apparently a Lockout Timer for the gas flow:
http://farm8.staticflickr.com/7323/1...56224304_o.gif

The PDF does not explain how that lockout timer works though ...

Danny D'Amico has brought this to us :
On Tue, 10 Dec 2013 22:57:30 -0500, Rick wrote:

The schematic should be attached to the inside of one of the covers on the
furnace.....

It is. There are actually *two schematics* on that inside cover.

I'm not sure how this lockout timer module works; but it might be the
culprit: http://farm6.staticflickr.com/5518/1...27d0a8ef_o.gif

Otherwise, this is the schematic:
http://farm3.staticflickr.com/2863/1...ef8ce342_o.gif

Two things.
The timer is there to set delays between various operatins and you will
be very confused if you expect things to happen immediatly whenever the
conditions change.

The Thermostat must always be mounted as though it was on the wall so
that the mercury switches will operate correctly.

--
John G

On Tue, 10 Dec 2013 23:00:54 -0500, Stormin Mormon wrote:

So now that I've identified "most" of the parts (I'm not sure what
the purpose of the lockout timer and that sensor thing are), it's
time for me to figure out what/how to test and debug the thing...

IIRC, your manual mentioned spark ignitor.

I think the lockout timer and spark ignitor are two different things:

Here is the spark igniter (I think):
http://farm6.staticflickr.com/5493/1...04b85a9f_o.gif

Here is the lockout timer (I'm sure - because it says so):
http://farm8.staticflickr.com/7323/1...56224304_o.gif

The PDF doesn't describe the lockout timer; but there is a schematic
pasted on the inside of the furnace door that purports to describe it:
http://farm6.staticflickr.com/5518/1...27d0a8ef_o.gif

I'm still not sure how it works though - but maybe it is the culprit...

I think you're having fun, but you really need to call the man.

I'm getting close because, for a while, tonight, it was all working:
http://farm8.staticflickr.com/7427/1...ceb36cd5_o.gif

But, then it stopped as soon as I accidentally allowed the door switch
to spring open (I bumped it while trying to measure voltages).

On Tue, 10 Dec 2013 18:46:02 -0600, Irreverent Maximus wrote:

Was the blower running at this time?

I think the blower was running constantly at that time,
so, I must have opened the door to stop it from running ...

On Tue, 10 Dec 2013 13:31:33 -0700, Tony Hwang wrote:

Close the cover. And shut the power off to the furnace for 5 mins or so
and turn on the power. What happens now? Still fan comes on? Then we'll
do next step. Usually when hi temp limit switch(fixed temp. thermostat)
triggers furnace flame shuts off and fan runs to cool and when that
switch opens, fan will stop. I don't think your furnace is hot now.
Just maybe thatr switch is stuck close.(this is just one of possible
scenarios)

If this is the case furnace will lock up 2 hours something like that.
By turning power on/off you can defeat that 2 hour wait to try again.
Is it cold there? It is -14C and light snow here today.

Something I did must have worked, at least temporarily, because I got
pilot light finally tonight:
http://farm3.staticflickr.com/2845/1...8bf71569_o.gif

And then I got main burner:
http://farm8.staticflickr.com/7397/1...80c6d243_o.gif

And then I got blower:
http://farm8.staticflickr.com/7427/1...ceb36cd5_o.gif

But, I accidentally loosened the tape holding the door switch in,
so the whole thing died.

Trying again and again, I was able to get it to restart a couple of
times, but it shuts off almost immediately - like after just a minute
or two - so I have to figure out what's turning it off ...

On Tue, 10 Dec 2013 19:01:35 -0600, philo wrote:

If you hear a click and gas starts to flow, but nothing ignites, then it
shuts down...then the igniter is bad.

After wiggling and tapping everything I could on all the connections and
circuit boards, I was able to get the full sequence of clicking, pilot lighting,
burners lighting, and fan blowing.
http://farm8.staticflickr.com/7427/1...ceb36cd5_o.gif

But, the furnace seems to shut down too quickly; like after a minute or two.
Then I can't get it restarted again.

I will test again in the morning.

On Tue, 10 Dec 2013 18:18:16 -0700, Tony Hwang wrote:

Just jumper W and C at the furnace after taping down the cover
interlock switch.

I'm confused as most people said to jumper R & W, not W & C.
Plus, there are two W wires!
http://farm8.staticflickr.com/7443/1...bf7cb9e1_o.gif

Which W would you suggest I jumper to C?

Rick wrote:

"Danny D'Amico" wrote in message
news
On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

1st: Remove furnace access door (effectively cuts off control power).
2nd: Put thermostat back together making sure that all switches
are in
the -off- position, and turn the temperature select to its
lowest
setting.
3rd: Replace furnace door.
Does the blower immediately turn on still?

Nope. Now the blower doesn't go on at all when I hold down the furnace
door
switch. I did hear some snapping at one point, but then it went away.
It was like a sharp click click click...


That's the igniter...



So I opened the blower door (to interrupt the power) and gently tapped on
everything, especially the solenoids; and I wiggled all the wires. I
found
one that seemed loose; and now it's back on tightly...

On Tue, 10 Dec 2013 18:01:05 -0700, Tony Hwang wrote:

Can you id. parts in the furnace like piezo ignitor, limit switches

Here's what I've identified, so far:

This is the "3-wire pilot assembly":
http://farm3.staticflickr.com/2812/1...8e651e36_o.gif

This is the high-voltage ignitor:
http://farm6.staticflickr.com/5493/1...04b85a9f_o.gif

This is the "gas valve" (I tapped on both solenoids):
http://farm8.staticflickr.com/7358/1...fbde6523_o.gif

This is a fusible link and something called a "lockout timer":
http://farm8.staticflickr.com/7323/1...56224304_o.gif

This appears to be the Limit Switch (I can't find the VSSS):
http://farm3.staticflickr.com/2814/1...0de1c8bd_o.gif

This compartment holds the fan-control PCB:
http://farm6.staticflickr.com/5503/1...351134b4_o.gif

This is the terminal set from the thermostat (and elsewhere):
http://farm3.staticflickr.com/2849/1...e7793ca9_o.gif

This 3 Amp fuse tested good:
http://farm4.staticflickr.com/3759/1...c03444e1_o.gif

This is the "fan control board":
http://farm8.staticflickr.com/7443/1...bf7cb9e1_o.gif

This is the door safety switch:
http://farm4.staticflickr.com/3789/1...1f88de9a_o.gif

This is the on/off switch for the gas, which remains on:
http://farm8.staticflickr.com/7295/1...4cc8b179_o.gif

This is the 16x25x1 3M filter:
http://farm3.staticflickr.com/2814/1...7ba0ef50_o.gif

At the moment, I'm trying to figure out how to test the lockout
timer, which might be preventing the propane gas from flowing ...

On Wed, 11 Dec 2013 04:24:22 +0000, Danny D'Amico wrote:

I *did* read the entire PDF sent to me by the Carrier company,
which explained how the system works by connecting "red" 24VAC
power to Red to "call for heating".

OOps. Red to white!

Danny D'Amico wrote:
On Tue, 10 Dec 2013 18:19:44 -0600, Irreverent Maximus wrote:

Does the blower immediately turn on still?
If no: Switch thermostat to -heat- and set to highest temperature. Go
back to the furnace and listen. The blower should be running and
in a minute, or so, the burner should kick on. This unit might have
a delay for the blower, so wait 2 minutes before deciding that things
are not functioning. That is it for this part until you come back
with an answer.
If Yes: Either the heating or the cooling relay is sticking. Once again, get
back with an answer.

Wow. I tried this just now, in the dark, and, for a short while, everything was
working again!

The click click click I had heard was a snapping sound as the pilot was being
lighted. Soon, the pilot light lit!
http://farm3.staticflickr.com/2845/1...8bf71569_o.gif

Then, after about a minute (I didn't measure it), the entire burner was aflame!
http://farm8.staticflickr.com/7397/1...80c6d243_o.gif

And, within another while (again, I didn't think to measure), the blower ran!
http://farm8.staticflickr.com/7427/1...ceb36cd5_o.gif

I accidentally hit the door switch while I was trying to measure voltages,
so the whole thing shut down - and I couldn't reproduce the success - but -
I'll try again tomorrow when I have more light to work with (and it will
be warmer besides, as it's going to be at freezing tonight).

Hi,
Leave that door open for now and tape down the switch. You may have a
intermittent ignitor. This is the one like BBQ lighter. When you hear
zapzap sound, you should be able to see spark. Remove the tape and close
the cover when problem is solved. Piezo ignitor is known to go bad when
old. I used to have that problem in my 5th wheel camping trailer fridge.
Only remedy is replacing whole module.

On Wed, 11 Dec 2013 15:44:56 +1100, John G wrote:

The timer is there to set delays between various operatins and you will
be very confused if you expect things to happen immediatly whenever the
conditions change.

This is very interesting.

My wife constantly turns the thermostat off and back on.

Should we be more, shall I say, "graceful" about adjusting the thermostat?h