Blower Runs - No Aux Heat


Old 11-21-07, 08:35 PM
Thread Starter
Join Date: Nov 2007
Posts: 2
Blower Runs - No Aux Heat

I have a comfortmaker furnace that is about 5 years old. The heat pump and A/C work fine. What happens is that when the thermostat calls for aux heat the blower will kick on and run constantly, but the burners will not ignite.

I can get the burner to ignite if I try these things but I am afraid to run it that way in fear of ruining something.

-If I pull Vacuum on the pressure switch the burners will ignite.

-If I remove the hose from the pressure switch that goes to the burners, the burners will also ignite.

The inducer fan motor was replaced because it shorted out. The pressure switch was replaced also. Please Help as it has started to get cold and I need heat.
Sponsored Links
Old 11-22-07, 10:50 AM
Join Date: Aug 2007
Posts: 2,021
Hi Joe:

Try checking the piping to see if there's any obstructions. A cracked heat exchanger could also give the same symptoms, so make sure you have some functioning CO detectors in you home. Let us know what you find. Thanks.
Old 11-22-07, 11:12 AM
Thread Starter
Join Date: Nov 2007
Posts: 2
I checked the exhaust piping and drain previously and it seems to be clear. I cut the intake pipe near the furnace and it seems to be working currently. I will have to wait until the snow melts before I can climb on the roof and take a look at the pipe coming out of the chimney.

thanks for the help
Old 11-22-07, 11:29 AM
Join Date: Aug 2007
Posts: 2,021
You're welcome. You'll probably find that pipe is obstructed. Nothing better than a warm house and the smell of a roasting turkey. he he
Old 11-23-07, 09:45 AM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
You could quickly find out if it is the EXHAUST vent by disconnecting the pvc at the inducer. Obviously, due to CO you want this to be a very brief test. Then at least you will know if it is in the exhaust pipe and likely due to snow in an elbow in attic or ice formation that closed in the exhaust uptop. At least you will know, for sure. Let anyone else in the house know what you are up to if you disconnect that line, ever-so temporarily.

As soon as it ignites and runs for say 8 seconds, so you know a dirty flame sensor will not snuff it out, then shut off the furnace and rehook up the pvc pipe.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes