BoilerFaultCodesAlpha 02 Fault Code
The Alpha 02 fault code means: your boiler has switched itself off for safety because it has become too hot inside, likely due to a circulation blockage or a pump failure.. It appears on 24 Alpha models in our database.
Technical description: Overheat boiler lock out — overheat sensor has activated
DIY fix possible
Ensure all radiator valves (TRVs) are turned to their highest setting to allow water to flow.Check that the boiler pressure is between 1 and 1.5 bar on the gauge.Press and hold the 'R' reset button for several seconds to restart the boiler.
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A cover plan would handle faults like 02: no call-out fees, no surprise bills.
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Alpha models that show the 02 fault code
Click a model for the full fault code list and model-specific repair notes.
- CD18 / CD24 Repair: £120-250
- Cd50s Cd70s Repair: £120-250
- E-Tec 28 Repair: £120-250
- E-Tec 33 Repair: £120-250
- E-Tec NX Repair: £120-350
- E-Tec NXS Repair: £100-£250
- E-Tec Plus Repair: £120-250
- E-Tec Plus 10 / 18 Repair: £120-350
- E-Tec Plus 28 Repair: £120-250
- E-Tec Plus 33 Repair: £120-250
- E-Tec Plus NX Repair: £120-£350
- E-Tec Regular Repair: £150-300
- E-Tec S Repair: £100-£350
- Eco Repair: £120-250
- Eco 11 13 Repair: £100-£350
- Evoke Repair: £120-250
- Evoke 10 / 18 Repair: £100-280
- Evoke NX Repair: £100-£350
- Intec 40GS2 Repair: £120-250
- Intec 50CS Repair: £120-250
- Intec S Repair: £120-250
- Intec2 25 28XE Repair: £120-250
- Intec2 30SE Repair: £120-250
- SY9 24 Repair: £120-250
Source
Alpha 02 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026