Alpha Fault Codes
Searchable list
Boilers covered:
- E-Tec and E-Tec Plus
- E-Tec NX and E-Tec NXS
- E-Tec Regular
- Evoke and Evoke NX
- Intec and Intec²
- CD, CD S and CD Systematic
- Eco and Eco² Plus
- Pro Tec NX
- Alpha Pro Tec 50 / 70 / 90 / 115
- Alpha Pro Tec Plus 50 / 70 / 90 / 115
Note: Low-pressure codes (10, E10) are often user-fixable. Most others require a Gas Safe engineer.
Modern Codes (E-Tec / Evoke / NX)
| Error code | Possible fault | If ticked try the troubleshooter |
|---|---|---|
| 01 / E01 | Ignition failure / flame not detected | ✓ |
| 02 / E02 | Overheat boiler lockout | ✕ |
| 03 | High flue thermostat temperature | ✕ |
| 04 | Gas valve electrical connection fault | ✕ |
| 05 | CH flow sensor fault | ✕ |
| 06 | DHW sensor fault | ✕ |
| 08 | Maximum number of resets reached | ✕ |
| 10 / E10 | Primary system pressure low | ✓ |
| 12 | DHW inlet sensor fault | ✕ |
| 15 | Incorrect configuration | ✕ |
| 16 | Fan fault | ✕ |
| 20 | Flame sensing fault | ✕ |
| 23 | Return sensor fault | ✕ |
| 24 | Control panel button fault | ✕ |
| 27 / E27 | Insufficient primary flow | ✕ |
| 29 | Flue sensor fault | ✕ |
| 37 | Low supply voltage | ✕ |
| 43 | Loss of flame rectification | ✓ |
| 45 | High temperature difference between flow and return | ✕ |
| 47 / E47 | Exhaust thermostat intervention | ✕ |
| 60 | Pump error (stuck or electrical) | ✕ |
| 61 | Air in pump / restricted flow | ✕ |
| 70 | Return/flow sensor fault | ✕ |
| 75 / 76 | Return/flow sensor fault | ✕ |
| SR | Service reminder | ✕ |
Classic Codes (Pro Tec / Pro Tec Plus)
| Error code | Possible fault | If ticked try the troubleshooter |
|---|---|---|
| 0A1 | Ignition failure | ✓ |
| 0A2 | Flame detection fault | ✓ |
| 0A3 | Overheat thermostat lock-out | ✕ |
| 0A5 | Fan speed fault | ✕ |
| 0A7 | High flue temperature fault | ✕ |
| 0A9 | Gas valve electrical error | ✕ |
| 0A15 | Flow and return sensor anomaly | ✕ |
| 0A16 | Flow sensor temperature rise incorrect | ✕ |
| 0A17 | Return sensor temperature rise incorrect | ✕ |
| 0A18 | Flow and return sensor anomaly (sudden change) | ✕ |
| 0A21 | Main PCB fault | ✕ |
| 0A30 | Flow sensor short circuit | ✕ |
| 0A31 | Flow sensor out of range | ✕ |
| 0A37 | Insufficient system flow / pressure | ✓ |
| 0A43 | Return sensor short circuit | ✕ |
| 0A44 | Return sensor out of range | ✕ |
| 0A80 | Flow and return sensor connection fault | ✕ |