High
05 on Alpha Intec 40GS2

Your boiler has stopped working because it cannot correctly measure the temperature of the water flowing through your heating system.

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

Heating flow sensor fault - Incorrect flow sensor resistance value

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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