If the inside blower doesn't come on in the FAN only setting on the thermostat, The problem is inside the air handler unit and not the outside unit. The circuit board in the air handler is what controls the outside unit via the thermostat and transformer. Could be bad transformer, thermostat, thermostat wire, circuit board, no power to circuit board. Process of elimination starting with power to circuit board .
And to clarify, The fan only setting on the thermostat is for the blower in the inside unit. It has nothing to do with the outside condenser fan. My assumption when you said nothing happens when on Fan only was that there was no air coming from the vents.
And to clarify, The fan only setting on the thermostat is for the blower in the inside unit. It has nothing to do with the outside condenser fan. My assumption when you said nothing happens when on Fan only was that there was no air coming from the vents.
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