How much does it cost to fix Alpha error code A flashing?

Typical repair cost for the Alpha A flashing fault is £120-220 including labour.

A flashing High

Alpha A flashing Fault Code

Q: What does the Alpha A flashing fault code mean?

Your boiler's internal thermometer is malfunctioning, meaning the system can no longer tell how hot the water is and has stopped working to keep you safe.

Also written as AFLASHING — same fault.

The Alpha A flashing fault code means: your boiler's internal thermometer is malfunctioning, meaning the system can no longer tell how hot the water is and has stopped working to keep you safe.. It appears on 5 Alpha models in our database.

Technical description: Temperature sensor fault, contact your Service Engineer.

Typical repair cost £120-220 (including labour)

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 A flashing fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Alpha A flashing 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