Medium
31 on Alpha E-Tec 28

Your boiler has lost its digital connection to your room thermostat, meaning it no longer knows when to turn the heating 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

Loss of communication with external control (Alpha Climatic). Loss of connection between the boiler and Alpha Climatic control unit

From this model's manual
Verified against the Alpha E Tec Regular installation & service manual, page 47.
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 if the batteries in your Alpha Climatic controller are dead and replace them if necessary.Ensure the control unit is firmly mounted on its backplate to maintain a solid electrical connection.Turn the boiler off at the fused spur for 60 seconds and switch it back on to force a reconnection.

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