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rainman5573
Mar 22, 2009, 10:43 AM
My Bryant gas furnace's, (model 376CAV downflow), blower will not come on.
I removed the front doors and pushed re-set on the draft safeguard tube and the re-set for the manual limit switch. With the doors off, I can hold the blower door safety switch down and the blower comes on (does this mean the fuse is okay?) and the blower runs for a few minutes then turns off, then the burner comes on, but shuts off after a minute or two without the blower ever coming back on. With the doors replaced, the burner always comes on, but never does the blower. I have repeated this procedure several times with the same results. Is there something I can do to remedy the problem without the costly visit of a repairman?

Short history: flooding caused several heat ducts to fill with water. The water never reached the height of the furnace base, but was within +18". The water has has now receded and is no longer in the crawl space of the house.

rainman5573
Mar 22, 2009, 10:52 AM
I should add to my post that the burner always ignites when tripped by the thermostat, but the blower never does come on, without me going through the procedures mentioned in my post.
rainman5573

wmproop
Mar 22, 2009, 02:07 PM
Rainman,, its true (life is like a box of chocolates)
Does it (the led on circuit board ) give a blinking code? If so on the inside of the door/panel you should find something to tell you what the code is

You could also bypass the tstat bydisconnecting and jumpering the red and white tstat wires and see if you still have the problem

KC13
Mar 22, 2009, 03:38 PM
Inspect the circuit board for evidence of moisture exposure. Look for oxide bridging of the printed circuit paths and/or burned spots. While the standing water may not have reached the unit, misting in the duct system may have occurred.

mygirlsdad77
Mar 22, 2009, 04:45 PM
So you can get the blower to run, but it won't run normally during heating cycle? And water was in the crawlspace. With this info, I would say you have a bad board, as KC suggested. I would check power to blower motor when it should be running(at approriate lead, heat, cool, fan, etc. Im betting on a bad board, but more info would help.

It just so hard to trouble shoot this from here. I would hate for you to replace a board, or a motor, or anything for that matter, without being able to test it. Believe it or not, a visit from a repairman may actually save you money, vs replacing parts that may not be bad. Please let us know how things turn out. Good luck.

letmetellu
Mar 22, 2009, 07:25 PM
By any chance does this furnace have a test terminal on the Circuit board. If so follow the instructions for testing the different compontents of the furnace.

rainman5573
Mar 22, 2009, 08:10 PM
rainman,,,its true (life is like a box of chocolates)
does it (the led on circut board ) give a blinking code? if so on the inside of the door/panel you should find something to tell you what the code is

you could also bypass the tstat bydisconnecting and jumpering the red and white tstat wires and see if you still have the problem

WMPROOP, You are correct, and I failed to mention, there IS a blinking red light. The sequence is:
1 blink followed by 3 blinks (or is it 3 then 1?), then repeats continuously, but there is no info found anywhere that tells what this blink code means and the error codes seem to be the hardest info to find on the web except for all of the jokes.
The circuit board looks to be clean, free of dust AND corrosion. Maybe it is time to call for home service. I'm at a loss.

KC13
Mar 22, 2009, 08:50 PM
Observe the blinks. The first digit will be short, the second digit long. Example: 1 short, pause, 3 long, pause/repeat = 13. 3 short, pause, 1 long, pause/repeat = 31.

mygirlsdad77
Mar 23, 2009, 03:36 PM
Kc, where would the diagnostic codes be found on this furnace? Or is it one of those that doesn't give the codes.

KC13
Mar 24, 2009, 03:54 AM
A label titled "SERVICE" is usually found on one of the access panels, giving a description of the status LED and a list of the codes. Carrier, Bryant, and Payne use the same diagnostic format. The variable speed units can store fault codes for later retrieval, even if power has been interrupted.

rainman5573
Mar 27, 2009, 06:51 PM
So you can get the blower to run, but it wont run normally during heating cycle? And water was in the crawlspace. With this info, i would say you have a bad board, as KC suggested. I would check power to blower motor when it should be running(at approriate lead,, heat, cool, fan, etc. Im betting on a bad board, but more info would help.

It just so hard to trouble shoot this from here. I would hate for you to replace a board, or a motor, or anything for that matter, without being able to test it. Believe it or not, a visit from a repairman may actually save you money, vs replacing parts that may not be bad. Please let us know how things turn out. good luck.

I'm not quite sure how to thank everyone at once, so I have responded by "quoting" several of you who attempted to help me.
I DID finally call a local service man to the house, and thank goodness the "fix" was not any new parts for the furnace at all, just a $60 service call. The Bryant user's manual didn't list the blinking LED error codes and I missed seeing one of the re-set buttuons.
All it took was re-setting the "manual-reset auxiliary limit switch" located on the blower housing. Easy to miss, as it is not readily seen behind the housing itself.
Thank you to KC13, Mygirlsdad77, letmetellu and wmproop for your good advice!

rainman5573
Mar 27, 2009, 06:51 PM
A label titled "SERVICE" is usually found on one of the access panels, giving a description of the status LED and a list of the codes. Carrier, Bryant, and Payne use the same diagnostic format. The variable speed units can store fault codes for later retrieval, even if power has been interrupted.

I'm not quite sure how to thank everyone at once, so I have responded by "quoting" several of you who attempted to help me.
I DID finally call a local service man to the house, and thank goodness the "fix" was not any new parts for the furnace at all, just a $60 service call. The Bryant user's manual didn't list the blinking LED error codes and I missed seeing one of the re-set buttuons.
All it took was re-setting the "manual-reset auxiliary limit switch" located on the blower housing. Easy to miss, as it is not readily seen behind the housing itself.
Thank you to KC13, Mygirlsdad77, letmetellu and wmproop for your good advice!

letmetellu
Mar 28, 2009, 09:23 AM
My Bryant gas furnace's, (model 376CAV downflow), blower will not come on.
I removed the front doors and pushed re-set on the draft safeguard tube and the re-set for the manual limit switch. With the doors off, I can hold the blower door safety switch down and the blower comes on (does this mean the fuse is okay?) and the blower runs for a few minutes then turns off, then the burner comes on, but shuts off after a minute or two without the blower ever coming back on. With the doors replaced, the burner always comes on, but never does the blower. I have repeated this procedure several times with the same results. Is there something I can do to remedy the problem without the costly visit of a repairman?

Short history: flooding caused several heat ducts to fill with water. The water never reached the height of the furnace base, but was within +18". The water has has now receded and is no longer in the crawl space of the house.

In the past I have found two thing that can cause a furnace like yours to operate the way you describe, one is to have a dirty filter, the other is to have a evaporator coil for the A. C. partially stopped up therefore acting the same as a dirty filter would.

If enough air does not go across the heat exchanger the burners will turn off from over heating, it will do this for a few times and then it will go into shutdown. When you open the bottom door of the furnace you break the power to the unit and this resets the shutdown, then it goes through the procedure all over again.