Emergency
F.27 on Vaillant ecoTEC Plus 610

Your boiler has detected an issue with its flame monitoring system and has automatically shut down to ensure your safety.

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

Safety switch-off: Fault in flame detection. Moisture on the electronics, electronics (flame monitor) defective, gas solenoid valve leaking

From this model's manual
Verified against the Vaillant Ecotec Plus 610 installation & service manual, page 33.
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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Related fault codes

F.28View →F.29View →

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