blower comes on by itselfgreenspun.com : LUSENET : Freedom! self reliance : One Thread
Here's the situation: thermostat set in off mode for cooling and heating; fan switch in auto mode. Blowers kick in out of nowhere and run for about 2-3 minutes before shutting down. After a few minutes, the blowers start again for same duration. Thinking it was a bad thermostat (digital), I replaced it with the original (mercury level). Same result. BTW, heating and cooling work fine when in operation mode. My questions: 1) Why does the blower come on by itself when thermostat is set to off? 2) Is the fix a DIY? 3)How much $$? Appreciate info regarding this. One last thing, it seems to do this most oftern when the air temperature is cool (<70F).
-- az penguin (firstname.lastname@example.org), November 12, 2003
Try sending an email to this guy - email@example.com He's a whiz on heating and air conditioning. John
-- John in S. IN (firstname.lastname@example.org), November 13, 2003.
if no heat is coming on at that time, then you have a bad thermocoupler, thats my guess. If you have heat,, bad therostat or a bad switch
-- Stan (email@example.com), November 17, 2003.
Az. Problem is in the fan switch. Heat is building up in the furnace from probably a pilot light, causing it to kick on the blower. This is normal sometimes and won't hurt anything however it can be annoying. Solution is to turn power off to the furnace, turn off pilot or change the temp setting on the fanswitch. old hoot. Matt. 24:44
-- old hoot gibson (firstname.lastname@example.org), December 01, 2003.