American Standard- TUD100C936A
#1
American Standard- TUD100C936A
This might have been asked before, but we have a gas furnace, see the subject line. No pilot light obviously. It blows warm air for 30 to 60 minutes (sometimes less), then runs cool air. We reset it and it does the same thing.
Filters are changed on routine, but it's been 1.5 yrs. since cleaned. Could this be the problem? I realize I should clean it first to find this out.
Tips on cleaning this furnace are appreciated. The manuals I have are limited on that info.
I would like to fix this myself w/o a service person, but will call one if it comes to that.
Thanks in advance.
Filters are changed on routine, but it's been 1.5 yrs. since cleaned. Could this be the problem? I realize I should clean it first to find this out.
Tips on cleaning this furnace are appreciated. The manuals I have are limited on that info.
I would like to fix this myself w/o a service person, but will call one if it comes to that.
Thanks in advance.
#2
Join Date: Feb 1998
Location: The Shake and Bake State USA
Posts: 9,927
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Hello MelloYello. Welcome to the Gas Heating forum & the Do-It-Yourself Web Site.
There could be any number of possible causes for a furnace to cycle off too soon. In order to help us help you, more details need to be known.
Furnace age would be helpful.
What do you mean by reseting it? Reset what?
Does the fan continue to run long after the burners shut down?
Does the room temp ever raise to the thermostat set temp?
Does the unit have A/C? Possible the A/C coils are restricted.
Possible venting problem causing the safety device to shut it down. Or the flame senser is dirty? Solenoid in the gas valve may be defective.
Lots of possibilities. Kindly use the reply button to add more specific and detailed information from which the professionals can determine the cause. Thanks.
Regards. Sharp Advice.
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Web Site Host, Forums Monitor, Gas Appliances Topic Moderator & Multiple Forums Moderator. Energy Conservation Consultant & Natural Gas Appliance Diagnostics Technician.
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There could be any number of possible causes for a furnace to cycle off too soon. In order to help us help you, more details need to be known.
Furnace age would be helpful.
What do you mean by reseting it? Reset what?
Does the fan continue to run long after the burners shut down?
Does the room temp ever raise to the thermostat set temp?
Does the unit have A/C? Possible the A/C coils are restricted.
Possible venting problem causing the safety device to shut it down. Or the flame senser is dirty? Solenoid in the gas valve may be defective.
Lots of possibilities. Kindly use the reply button to add more specific and detailed information from which the professionals can determine the cause. Thanks.
Regards. Sharp Advice.
TCB4U2B2B Business Management Services.
Web Site Host, Forums Monitor, Gas Appliances Topic Moderator & Multiple Forums Moderator. Energy Conservation Consultant & Natural Gas Appliance Diagnostics Technician.
Personal Reminder:
Buckle Up & Drive Safely.
"The Life You Save, May Be Your Own."
#3
Thank you for the fast response.
The furnace is 12 yrs. old (original w/ the house).
Reseting it after the lock out. At the thermostat - Off, on, off, on within 30 seconds.
Yes, fan continues to run.
Yes, the temp does raise to the thermostat.
No A/C.
Thanks for the other hints too...
It calls for heat for awhile, then stops. When the burners try to re-ignite they'll burn for 5 - 10 seconds..then shut down. The fan continues to run and the light flashes indicating a lock out.
Perhaps I should clean the flame sensor first.
The furnace is 12 yrs. old (original w/ the house).
Reseting it after the lock out. At the thermostat - Off, on, off, on within 30 seconds.
Yes, fan continues to run.
Yes, the temp does raise to the thermostat.
No A/C.
Thanks for the other hints too...
It calls for heat for awhile, then stops. When the burners try to re-ignite they'll burn for 5 - 10 seconds..then shut down. The fan continues to run and the light flashes indicating a lock out.
Perhaps I should clean the flame sensor first.
#5
What kind of igntion does this have?
-Spark
-Hot Surface Ignitor "HSI" (glows red)
The sensor may need to be clean if there is one.
If there is none, then you may need to replace the HSI, some HSI are used as a sensor. but DO NOT clean it since it will break. If you do get a new one, DO NOT touch the black stuff, it will shorten the life of the ignitor.
-Spark
-Hot Surface Ignitor "HSI" (glows red)
The sensor may need to be clean if there is one.
If there is none, then you may need to replace the HSI, some HSI are used as a sensor. but DO NOT clean it since it will break. If you do get a new one, DO NOT touch the black stuff, it will shorten the life of the ignitor.