A hum followed by a click sound is an indication of a failure at the compressor. Possibly the compressor motor has gone into a locked rotor condition. A locked rotor condition can be checked using an ammeter. The name plate on the compressor will have a rating after LRA. If the ammeter reading is equal to the LRA rating the compressor is done. If it is a reading of about 80% of the LRA (locked rotor amperage) it is possible that a relay or capacitor has failed which is replaceable.
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A hum followed by a click sound is an indication of a failure at the compressor. Possibly the compressor motor has gone into a locked rotor condition. A locked rotor condition can be checked using an ammeter. The name plate on the compressor will have a rating after LRA. If the ammeter reading is equal to the LRA rating the compressor is done. If it is a reading of about 80% of the LRA (locked rotor amperage) it is possible that a relay or capacitor has failed which is replaceable.