Medium
58 on Viessmann Vitodens 100-W B1GA

Your boiler is struggling to understand the current temperature of the room, which may prevent your heating from turning on or off correctly.

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

Short circuit, 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.

DIY fix possible

Check if your thermostat or room sensor has run out of batteries.Ensure the thermostat is not placed too close to a heat source or in a cold draught.Try restarting the boiler at the main control panel to see if the error clears.

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