26 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is not running because the main power switch on the control panel has been turned off.
Your boiler has stopped working because an internal electrical fuse has likely blown, cutting power to essential safety or control parts.
Your boiler has detected an internal electronic failure related to the indicator lights on the control panel.
Your boiler is failing to ignite or stay running when the heating is turned right up, which means you will likely have no central heating.
Your boiler is failing to ignite or stay running when you turn on a hot water tap, meaning you currently have no hot water.
Your boiler has detected an issue with the automatic air vent, which helps remove trapped air from the system.
Your boiler is struggling to transfer heat between its internal systems, which means it cannot reliably provide hot water or heating.
Your boiler has detected an issue with the internal fan, which is responsible for safely removing harmful exhaust gases outside your home.
Your boiler is failing to ignite the flame needed to produce heat and hot water.
Your boiler's internal gas system is not running correctly, meaning the unit cannot safely ignite to provide heating or hot water.
Your boiler is not detecting the correct airflow needed to operate safely, so it has shut itself down to prevent any issues.
Your boiler has detected an issue with the fuel supply or combustion process, meaning it has safely shut itself down to prevent unsafe operation.
Your boiler has detected an issue with the fuel delivery system specifically related to the propane gas supply, preventing it from igniting safely.
Your boiler has identified a problem with how the gas-to-air mixture is being delivered to the burner, which indicates an issue with your fuel supply settings.
Your boiler has temporarily stopped working because it cannot safely detect the burner flame.
Your boiler is unable to regulate the gas supply correctly, which is preventing it from firing up to provide your heating and hot water.
Your boiler has detected an issue with its internal gas supply system which is preventing it from heating your home safely.
Your boiler has stopped working because a control switch inside may be in the wrong position or the unit has become too cold.
Your boiler has detected low water pressure or trapped air in the system, which stops it from operating safely.
Your boiler has stopped working because it is not receiving enough gas to ignite properly.
Your boiler has stopped working because an internal wiring connection inside the casing has come loose.
Your boiler has detected an internal electronic conflict where it is receiving signals to do multiple opposing jobs at the exact same time, causing the system to safely lock out.
Your boiler has encountered an uncommon or general safety lock-out fault that requires a professional engineer to diagnose safely.
Your boiler has automatically shut down because the main internal temperature has climbed too high, which is a vital safety measure to prevent damage.
Your boiler has detected a problem with one of its temperature sensors, so it has safely shut down to prevent overheating.
Your boiler has safely shut itself down because it failed to ignite properly.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes