The following table lists the fault register values and their meanings for each software version. All descriptions are provided in English.
| Register value | L/M software | H/J software |
|---|---|---|
| 0 | No fault | No fault |
| 1 | Fault N17.1 | Fault N17.1 |
| 2 | Fault N17.2 | Fault N17.2 |
| 3 | Fault N17.3 | Compressor load |
| 4 | Fault N17.4 | Coding |
| 5 | Reserved | Low pressure |
| 6 | Electronic expansion valve | Frost protection |
| 7 | Reserved | Outdoor sensor short or open circuit |
| 8 | Reserved | Return sensor short or open circuit |
| 9 | Reserved | Domestic hot water sensor short or open circuit |
| 10 | WPIO | Frost protection sensor short or open circuit |
| 11 | Reserved | 2nd heating circuit sensor short or open circuit |
| 12 | Inverter | Anti-freeze sensor short or open circuit |
| 13 | WQIF | Low pressure brine |
| 14 | Reserved | Motor protection primary |
| 15 | Sensor fault | Flow |
| 16 | Low pressure brine | Domestic hot water |
| 17 | Reserved | High pressure |
| 19 | Primary circuit fault | Hot gas thermostat |
| 20 | Defrost fault | Cooling operating limit |
| 21 | Low pressure brine fault | Reserved |
| 22 | Domestic hot water fault | Reserved |
| 23 | Compressor load fault | Temperature difference |
| 24 | Coding fault | Reserved |
| 25 | Low pressure fault | Reserved |
| 26 | Frost protection fault | Reserved |
| 28 | High pressure fault | Reserved |
| 29 | Temperature difference fault | Reserved |
| 30 | Hot gas thermostat fault | Reserved |
| 31 | Flow fault | Reserved |
| 32 | Warm-up fault | Reserved |