what would cause the AC to be on when I only have the heat on?
the button for the AC is off in the car, but the compressor kicks on under the hood.If AC is disconnected I get hotter air.
Do you have it on the defrost setting?
Like mwelk said, it will cycle when the defroster is on, but if it is cycling a lot then you may have low refrigerant. If so you may have a leak and should take it to a pro.
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