High
51 on Alpha Eco 11 13

Your boiler has lost its wireless connection with your thermostat or remote control, meaning they can no longer talk to each other to manage your heating.

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

Error between the communication of the Climatic transmitter and boiler receiver

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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