Emergency
F.25 on Vaillant ecoFIT pure

Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent overheating or fire risk.

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.

Technical description

Safety switch-off: Flue gas temperature too high

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.22View →F.23View →F.24View →

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