12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because an internal electrical safety fuse has blown, meaning the system is currently unable to power its internal components.
Your boiler has stopped working because an internal safety fuse has blown, preventing the electronic control system from powering up.
Your boiler's air extraction system is struggling to maintain a steady speed, which prevents the unit from starting or running reliably.
Your boiler has no electricity flowing to it, meaning it cannot start up to provide heating or hot water.
Your boiler is failing to detect an electrical power supply, meaning it cannot switch on or operate your heating and hot water.
Your boiler has stopped working because a safety sensor has triggered a shutdown to prevent it from getting too hot.
Your boiler has stopped heating because it has detected a heat safety issue and automatically shut down to prevent damage.
Your boiler has detected an issue with its internal air supply system, which is preventing it from igniting or staying lit.
Your boiler is failing to confirm that the flue system is clear, which is preventing it from igniting for your safety.
Your boiler has stopped working because the main control panel is failing to send electrical power to the internal gas valve to start the heating process.
Your boiler has stopped working because the internal control board is failing to send electrical power to the gas valve.
Your boiler is failing to ignite because the small flame that acts as a match to start the main burner will not stay lit.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes