Medium
57 on Viessmann Vitodens 100-W B1GA

Your boiler has lost communication with its room thermostat or temperature sensor, meaning it cannot tell how warm your house is.

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

Lead break, room temperature sensor

From this model's manual
Verified against the Viessmann Vitodens 100 W B1ga installation & service manual, page 53.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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