My heat comes on and you can hear the condenser unit come on as well. However the fan is not turning? The outside temp is 30 degrees? Is this normal?
Can anyone share some wisdom on this? Thank you.
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Under low ambient conditions, the pressures and temperatures in an air conditioner or heat pump will go off-kilter, eventually to the point where the unit no longer functions due to a coil freezeup or worse yet, liquid refrigerant re-entering the compressor and killing it. In order to mitigate this, a properly configured heat pump (for most climates) will have some form of low ambient control that manipulates the heat pump's operating parameters to keep it going (and heating your house). (This is in addition to other accessories, such as a crankcase heater that keeps the oil from gumming up.)
One of the more common forms of low ambient control modulates (either on/off as on yours, or actual variable speed on more sophisticated units) the outdoor unit fan to allow the outdoor coil to run at the correct temperatures and pressures despite the dropping ambient temperature conditions. Hence, if you observe your outdoor unit for a while, you should see the fan on it cycle intermittently -- this is the low ambient control working.