High
F31 on Viessmann Vitodens 025-W, BPKB-24

Your Viessmann boiler has detected an internal communication or sensor error, resulting in a safety shutdown that stops your heating and hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Fault message F31

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 025 W 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F30View →F36View →F38View →

All 27 fault codes on the Vitodens 025-W, BPKB-24

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

03040508F0AF0bF0CF02F03F04F05F07F08F09F10F18F30F38F39F51F59FA9Fb0Fb8FF1FF2

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