Medium
F10 on Viessmann Vitodens 025-W

Your boiler has lost connection with the sensor that monitors the weather outside, which may cause your heating to run at the wrong temperature.

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, outside temperature sensor

From this model's manual
Verified against the Viessmann Vitodens 025 W installation & service manual, page 59.
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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