Alpha Min - Max Fault Code
Also written as MINMAX — same fault.
The Alpha Min - Max fault code means: your boiler is currently in a manual setup mode for output adjustments rather than reporting a functional breakdown.. It appears on 4 Alpha models in our database.
Technical description: Adjustable operating curves (Blue LED)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Alpha models that show the Min - Max fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha Min - Max 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