6 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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.
Your boiler is struggling to light smoothly, causing a small 'pop' or bang sound when it tries to start instead of igniting quietly.
Your boiler is making loud banging or kettling noises because of internal debris buildup, incorrect gas settings, or restricted water circulation.
Your boiler is failing to ignite because it cannot start the small pilot flame required to trigger the main burner.
The small pilot flame that acts as a signal to ignite your boiler is too weak or flickering, so the system is shutting down for safety to prevent gas from escaping unburnt.
Your boiler is struggling to keep a steady flame, which suggests either moisture is trapped in the gas supply or the system cannot breathe properly through its exhaust.
BoilerFaultCodes