What does 5 mean?
Compressor internal thermal protector has opened due to overheating.
Common causes
- Low voltage causing high amp draw
- Locked rotor - failed start capacitor
- Low refrigerant causing high discharge temp
- Compressor run capacitor failure
- Undersized wiring causing voltage drop
Diagnostic & testing steps
- 1. Measure supply voltage at disconnect: should be 208-240VAC ±10%
- 2. Allow compressor to cool for 30 minutes before retrying
- 3. Test run capacitor: ±6% of labeled value
- 4. Measure LRA at startup and RLA at steady state
- 5. Check for low refrigerant charge
Tools required
- Multimeter
- Capacitor tester
- Amp clamp
OEM parts & part numbers
Compressor Run Capacitor, Compressor Start Capacitor, Compressor
Part numbers: CAP050370370RT, CAP050750440HT
Safety warning
⚠️ CAPACITORS CAN HOLD LETHAL CHARGE after power off. Discharge capacitor before handling.
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