Medium
F.57 on Viessmann Vitodens 222-F B2TF

Your boiler has lost its connection to the indoor thermostat or temperature sensor, meaning it doesn't know 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 222 F B2tf installation & service manual, page 89.
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 wireless thermostat has run out of batteries and replace them if necessaryEnsure the thermostat or room sensor is within range of the boiler and hasn't been movedCheck for any loose visible wires if your thermostat is the plug-in type

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