High
23 on Alpha Intec 50CS

Your boiler has detected a communication error with a temperature sensor, which is preventing it from heating your home safely.

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 return sensor fault - Incorrect return sensor resistance value (10 - 12 KΩ at room temperature)

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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