Medium
31 on Alpha Intec 50CS

Your boiler has lost its connection to its smart thermostat, meaning it cannot receive instructions on when to turn the heating or hot water on.

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 Intec 50cs 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 control unit are dead and replace them if necessaryEnsure the control unit is correctly docked or within range of the boilerTurn the boiler off at the fused spur for 60 seconds and then switch it back on to reset the connection

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