Emergency
BUBNEB STAYS ON on Chaffoteaux Britony II 50FF

Your boiler is failing to light properly because it cannot correctly detect or control the flow of gas, which may cause it to keep trying to fire up when it shouldn't.

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) Air in pipework; II) Gas valve stays open; III) Venturi blocked; IV) Dirt on gas valve facing; V) Loose jumper on house stop cock tap; VI) Dirt foreign matter is water section; VII) Slow ignition device stuck

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.

Find a Gas Safe engineer
Search the official register →

Related guides you might find useful

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →

Pilot light keeps going out

Older boilers — thermocouple, draught, gas supply.

Read →

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

Read →