Medium
51 on Alpha Eco

Your boiler has lost its wireless connection to the heating controller, so it no longer knows when to switch on or off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Error between the communication of the Climatic transmitter and boiler receiver

From this model's manual
Verified against the Alpha Eco installation & service manual, page 36.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that the batteries in your wall-mounted thermostat are fresh and workingTurn the power to the boiler off at the fused spur, wait 60 seconds, and turn it back on to reset the connectionEnsure the wireless receiver unit near the boiler is not obstructed by large metal objects

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