Medium
H.00.81 on Baxi Assure System

Your boiler has lost its connection to your digital wall thermostat or controller, meaning it cannot receive instructions on when to turn the heating 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

Room unit disconnected When removing the room unit, switch the power supply off and on again and set parameter CP780 =0 to remove the error.

From this model's manual
Verified against the Baxi Bm Baxi B Basic System 2 600 800 Assure 500 Isim 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 if your wall controller has batteries and replace them if they are flat.Restart your system by turning the boiler off at the fused spur for 30 seconds and turning it back on.Check if the controller has been moved or if there is interference preventing the wireless signal from reaching the boiler.

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