34 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to ignite because it cannot detect a flame, meaning your heating and hot water will not work.
Your boiler is trying to light but cannot successfully ignite the flame to start heating your home.
Your boiler has detected an issue with the fuel supply system and has safely shut itself down to prevent it from operating incorrectly.
Your boiler has stopped working because it cannot safely ignite the flame due to an internal electrical communication error.
Your boiler has detected an internal computer error that is preventing it from running safely.
Your boiler has detected an internal computer error that is preventing it from starting up correctly.
Your boiler has detected an internal electrical issue with the mechanism that controls the gas supply, meaning it has safely shut itself down to prevent operation.
Your boiler's main control computer is experiencing an internal error and cannot operate safely, meaning your heating and hot water will not work.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage or safety issues.
Your boiler's main control computer is experiencing an internal error, meaning the system has stopped working to prevent further damage.
Your boiler has detected an internal electronic error within its main control system that is preventing it from operating safely.
Your boiler has detected an internal computer error which prevents it from operating safely.
Your boiler has detected an internal error within its main computer board, which has caused the system to shut down for safety.
Your boiler has detected an internal computer error that is preventing it from starting up correctly.
Your boiler has detected that the water inside the unit is getting too hot, so it has safely shut itself down to prevent damage.
Your boiler has detected that the water returning to it is much hotter than expected, causing it to shut down to prevent overheating.
Your boiler has detected that hot water is flowing in the wrong direction or is not circulating properly, causing it to shut down to prevent damage.
Your boiler is shutting down because the water inside is heating up much faster than it can be moved around your system.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling because the internal fan that clears out exhaust gases isn't spinning or reporting its speed correctly, so it has safely shut down to prevent unsafe operation.
Your boiler has detected that the internal fan responsible for venting exhaust gases safely is not operating correctly, so it has shut down to prevent unsafe operation.
Your boiler has detected that your heating pipes are not transferring heat effectively, usually caused by a blockage in the system or the pump struggling to move water around.
Your boiler has lost its ability to measure the temperature of the water inside the system because a sensor is sending an invalid electrical signal.
Your boiler's internal thermometer is malfunctioning, meaning the system can no longer accurately read the temperature of the water returning from your radiators to safely manage the burner.
Your boiler has stopped providing hot water because it is having trouble reading the temperature of the water coming out of the tap.
Your boiler is struggling to detect the flow of water through the system, which is preventing it from safely heating your home or water.
Your boiler has lost the ability to read the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler is struggling to accurately detect the temperature of the water used for your taps and shower, causing the system to stop heating your water.
Your boiler has detected an internal computer error that is preventing it from operating safely.
Your boiler's computer is experiencing an internal error, which means the system has stopped working until it can be reset or repaired by a professional.
Your boiler is struggling to breathe properly because it cannot push out waste gases, so it has safely shut itself down to prevent any issues.
Your boiler has lost communication with its control system, preventing it from starting up correctly.
Your boiler is failing to ignite because it cannot detect a flame, meaning you will currently have no heating or hot water.
Your boiler has stopped working because an internal electrical safety fuse has blown, meaning the system is unable to power its own electronic controls.
BoilerFaultCodes