19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to ignite because it is not receiving the necessary electrical signal to release the gas required for the flame.
Your boiler is failing to ignite because the small flame that starts the main burner is not lighting, meaning you currently have no heating or hot water.
Your boiler has stopped working because a protective electrical fuse on its internal brain board has blown, cutting off power to the system's control components.
Your boiler has stopped working because a protective electrical fuse inside the control unit has blown, cutting off power to key components.
Your boiler is not receiving any electricity, which means it has completely shut down and cannot heat your home or water.
Your boiler is failing to start because it is not receiving a consistent or correctly connected power supply.
Your boiler is not receiving any electricity, which means it cannot power up to provide heating or hot water.
Your boiler has stopped working because a safety switch has detected that the unit became too hot and triggered a shutdown.
Your boiler has stopped working because a safety sensor has tripped, likely due to the system getting too hot.
Your boiler has stopped working because a safety sensor has detected that the unit became too hot and triggered an automatic shutdown.
Your boiler has automatically turned itself off because it detected that it may be getting too hot, likely to protect the system from damage.
Your boiler has detected an issue with its internal air supply system, which is preventing it from safely starting up the burner.
Your boiler is failing to detect the airflow needed for safe operation, likely due to an internal electrical connection issue or a faulty main control board.
Your boiler is failing to detect that it is safe to ignite, meaning it has shut down to protect your home and will not provide heating or hot water until repaired.
Your boiler is failing to clear combustion gases properly, so it has safely shut itself down to prevent any risk.
Your boiler has stopped working because it cannot detect or signal that it is ready to fire up, likely due to an internal electrical communication fault.
Your boiler's control system is failing to send the necessary electrical signal to the gas valve, meaning the boiler cannot ignite to provide heating or hot water.
Your boiler has detected an internal communication failure and needs a professional electrical check to restore heating and hot water.
Your boiler is failing to light the internal flame needed to produce heat or hot water.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes