High
BUBNEB STAYS ON on Chaffoteaux Britony Duo 55

Your boiler is failing to ignite properly because debris or trapped air is interfering with the gas or water flow, meaning your heating and hot water will not work.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

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 high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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