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I need more information. What is the make and model of this furnace?
Honeywell modelTH4210D1005 0732
That is your thermostat. I need furnace make and model
ARI Mode EIRD036S06B
The model number should be on a tag inside the top furnace door. The reason I ask for this is in case I need a wiring diagram. The ARI number is XXXXX the model.
This # XXXXX on outside of furnace which sits outside and has no easy door to get into.
OK, so this is a package unit correct? Approximately how old is it?
There are 2 possible reasons why the fan may kick on occasionally with system switch in the off position: a bad thermostat or a bad control board.
okay I will try to find somebody to look at it. thanks
If you take the green wire off the G terminal at the furnace board and this still occurs, that would tend to eliminate the thermostat as the culprit
I probably shouldn't play with wires etc.!!!
OK, I understand. LOL
Sometimes a thermostat can be faulty and send a signal to the board causing fan to come on. Other times a bad board will do that
I think you have done all you can from where you are. Thanks
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