Emergency
PILOT WILL NOT STAY ALIGHT on Chaffoteaux Britony II 40FF

Your boiler's small starter flame keeps blowing out or failing to stay lit, which prevents the main boiler from igniting and providing heating or hot water.

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

I) Thermocouple not working; II) Thermo-electric valve faulty; III) Gas pressure low/variable; IV) Terminal wrongly positioned; V) Badly assembled flue; VI) Gas pressure too hight

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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