Low
10 on Viessmann Vitodens 200-W WB2C 35kW Combi

The boiler has lost track of the outside weather, so it is heating your home as if it were freezing outside, which can make it run hotter than needed, though heating and hot water should still work.

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

Regulates as if the outside temperature were 0 °C. Cause: short circuit, outside temperature sensor

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W Wb2c Service 5692857 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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Related fault codes

18View →

All 82 fault codes on the Vitodens 200-W WB2C 35kW Combi

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

4C9A9b9C9E9F18202830384044485051585990919293949899A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCECFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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