The manual details a specific LED blinking pattern on the outdoor main PCB (CN20) that identifies firmware version 1.4 vs 1.5. Version 1.5 addresses a known cold-climate oil return issue.
| Error Code | Description | Common Fix | |------------|-------------|-------------| | | IPM Module Overcurrent | Check compressor winding resistance, replace IPM board | | P4 | Compressor Discharge Temp > 115°C | Low refrigerant charge, expansion valve stuck closed | | E1 | High pressure protection | Condenser coil dirty, fan motor failure, overcharge | | Ed | Communication fault between ODU and IDU | Broken H1/H2 wiring, wrong addressing | | L5 | Outdoor fan motor stall | Replace fan motor or check DC bus voltage |
The manual details a specific LED blinking pattern on the outdoor main PCB (CN20) that identifies firmware version 1.4 vs 1.5. Version 1.5 addresses a known cold-climate oil return issue.
| Error Code | Description | Common Fix | |------------|-------------|-------------| | | IPM Module Overcurrent | Check compressor winding resistance, replace IPM board | | P4 | Compressor Discharge Temp > 115°C | Low refrigerant charge, expansion valve stuck closed | | E1 | High pressure protection | Condenser coil dirty, fan motor failure, overcharge | | Ed | Communication fault between ODU and IDU | Broken H1/H2 wiring, wrong addressing | | L5 | Outdoor fan motor stall | Replace fan motor or check DC bus voltage |