Low
25:0 on Viessmann Vitodens 050-W

Your boiler has lost the connection to the external sensor that tells it how cold it is outside, meaning it may not adjust its heating output as efficiently as usual.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

No recognition of outside temperature sensor or remote monitoring (only in i).

From this model's manual
Verified against the Viessmann Vitodens 050 W Bpjd installation & service manual.
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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