i just used some sandpaper to brush off the carbon. would the pressure switch affect the heat output of the furnace. I have it running right now and i have a strong totally blue flame but the heat coming out of the vent is only slightly warm.

I think the pressure sensor might be bad. I talked to a friend of mine who is a tech and he had me turn the furnace on, unhook one of the wires from the pressure sensor and then plug it in a few seconds later and it started working! but now its not hiving hot air, just lukewarm. I did take the burne...

i have a coleman furnace model# DGAA090BDTA and the code light is flashing 3 times saying combustion air switch stuck closed). when i the thermostat tells it to turn on i hear a humming noise that goes on for about 30 seconds till the furnace stops trying to start. So i read about how the valve migh...