Turn thermostat down, does it click. Disconnect unit from mains, undo thermostat check working out of unit, make a drawing of which wire goes where, be careful with the capillary tube does not move easy. Thermostat slightly out of unit, should be able to see and hear switching. No switching replace. Switching, look to compressor, could be start capacitor. But you will need a meter to test compressor windings first.
SD
February 2013
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