What does the Alpha 25 fault code mean?

Your boiler has detected an abnormally fast rise in temperature and has shut itself down to prevent internal damage.

How much does it cost to fix Alpha error code 25?

Typical repair cost for the Alpha 25 fault is £150-350 including labour.

Manufacturer manual

Overheat lock out - Rapid temperature rise of flue sensor

Shared across the Alpha Intec² range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Boiler cover options

A cover plan would handle faults like 25: no call-out fees, no surprise bills.

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Seeing a different code? Every code this model can display, in one place.

Each noise points to a different fault.

7 signs repair isn't worth it anymore.

Break-even maths on monthly cover.