I recently installed thermostat and the fan on furnace won't shut off in auto mode?

Question

ritetemp 6025

Answer 1

check the wiring. "R" Red wire is power."G"  Green is for the fan. "W" White is for the heat, and"Y"  blue or yellow is for the a/c. If wire is too long also, it might be touching one of the other terminals causing fan to stay on all the time. Also if there is a short in the wire it can cause this also. But somewhere, the green wire is making contact with the red wire. Good luck

Answer 2

It could be that you have wired it up wrong-crossed the wires or you might have two wires touching, you might have gotten a defective thermostat (yes, sometimes these things can be bad out of the box) or maybe its just not compatible with your furnace...the wrong model thermostat for your furnace.

Do you know for certain if your fan wouldnt shut off before you replaced the old thermostat? If it was doing this before it might be something else not related to the thermostat. What was wrong with the old one-why did you replace it?

If everything seems to be wired up right and you still cant get it to work i would unhook it, hook the old thermostat back up and see what happens. If it continues to run while on auto then you might have another problem not related to the thermostat.

Answer 3

The G terminal is contacting the R terminal some how,or you got a bad t-stat right out of the box.

Answer 4

are you sure all the wires where connected correctly?