Emergency
F.347 on Vaillant ecoTEC Plus 832

Your boiler has detected water inside the part where the flame burns, which is preventing it from starting up safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Condensate has been detected in the combustion chamber. The burner operation is interrupted.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 91.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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