What does E229 mean?
Compressor internal protector opened due to high internal temperature.
Common causes
- Refrigerant undercharge
- High ambient temperature
- Low voltage
- Failed start components
- Compressor approaching end of life
Diagnostic & testing steps
- 1. Allow 30-minute cooldown before reset attempt
- 2. Measure supply voltage: 208-240VAC required
- 3. Test capacitors - run and start if equipped
- 4. Check refrigerant charge with gauges
- 5. Measure RLA at steady state - compare to nameplate
Tools required
- Multimeter
- Capacitor tester
- Manifold gauges
- Amp clamp
OEM parts & part numbers
Run Capacitor, Compressor
Part numbers: 90W56, 10L51
Safety warning
⚠️ CAPACITOR HAZARD: Discharge run capacitor before handling. Can retain 370-440VAC charge.
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