BoilerFaultCodesAlpha 99 Fault Code
The Alpha 99 fault code means: your boiler has detected a general internal fault that is preventing it from operating, which usually indicates an electronic control board or communication issue.. It appears on 6 Alpha models in our database.
Technical description: General block
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Alpha models that show the 99 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha 99 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