High
05 on Alpha E-Tec Plus 33

Your boiler is struggling to detect the temperature of the water flowing through your heating system, which is preventing it from heating your home properly.

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

CH 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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