Medium
F51 on Viessmann Vitodens 025-W

Your boiler has detected a fault with the sensor that monitors hot water temperature, meaning you will likely experience cold or lukewarm water from your taps.

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, DHW temperature sensor

Shared across the Vitodens 025-W, range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Related fault codes

F59View →F61View →F62View →

All 24 fault codes on the Vitodens 025-W

Seeing a different code? Every code this model can display, in one place.

F0AF0bF0CF02F03F04F05F07F08F09F10F18F30F31F38F39F58F59FA9Fb0Fb8FF1FF2

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