⚠ What This Means
The compressor does not start at all. No humming or clicking is heard, or the compressor hums briefly and then goes silent. Usually caused by a faulty relay/overload or a locked compressor rotor.
Caution: If the compressor has just cycled off, system pressures need time to equalize before the compressor will start. Wait several minutes before testing.
🔧 How to Fix
- Check that the unit is not in Shutdown Mode (display shows
--). Press COLDER if so. - Verify 115V is present across P6 & P5 at the control board.
- Use a starting cord to attempt to start the compressor directly.
- If the compressor starts with the starting cord: replace the relay and overload.
- If the compressor does not start: the rotor is locked — replace the compressor.
🛒 Replacement Parts for This Fix
Compressor Relay & Overload Kit
700 Series
Compressor Starting Cord
Testing tool
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