BoilerFaultCodesAlpha 0A9 Fault Code
The Alpha 0A9 fault code means: your boiler has detected an electrical fault in the system that controls the gas supply, meaning it cannot safely start up to provide heat or hot water.. It appears on 3 Alpha models in our database.
Technical description: Gas valve electrical error.
What causes the Alpha 0A9 fault?
This fault occurs when the boiler's main control board loses proper electrical communication with the gas valve, which is the component responsible for releasing fuel into the burner. It is typically caused by a loose connection in the internal wiring, a moisture-related short circuit, or a mechanical failure within the gas valve's solenoid coils.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Alpha models that show the 0A9 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha 0A9 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 27 April 2026