High
0A80 on Alpha FMK

Your boiler is struggling to monitor the temperature of the water moving through the system, which causes it to shut down after running for a short period.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flow and return sensor connection fault (may occur after several minutes of boiler operation.)

Engineer required

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

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