High
23 on Alpha E-Tec

Your boiler's temperature gauge is misreading, which prevents it from heating your home because it doesn't know the current temperature of the water returning to the 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

Return sensor fault - Return sensor resistance out of range

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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