Medium
51 on Alpha E-Tec Plus 10 / 18

Your boiler has lost its wireless connection to the external temperature controller, meaning it may not know when to turn 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 communication of the Climatic transmitter and boiler receiver

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 48.
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 the batteries in your wall-mounted thermostat or Climatic controller.Ensure the controller is within range of the boiler and there are no large metal objects blocking the signal.Try resetting the boiler and re-pairing the transmitter according to your manual.

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