What does the Alpha 25 fault code mean?

Your boiler has detected that it is heating up significantly faster than it should, so it has safely shut itself down to prevent damage.

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

Typical repair cost for the Alpha 25 fault is £150-300 including labour.

Overheat lock out - Rapid temperature rise of flue sensor

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

Each noise points to a different fault.

Sludge build-up — needs flushing, not bleeding.

7 signs repair isn't worth it anymore.