24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's air circulation system is failing to start, which means the unit cannot safely ignite to provide heating or hot water.
Your boiler is currently unable to read the temperature of the water flowing through it, so it has shut down to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of the water returning to it from your radiators, so it has shut down to prevent potential overheating.
Your boiler is having trouble communicating with the weather sensor mounted on the outside of your property, so it is using a default setting to keep your home warm.
Your boiler is perfectly capable of heating your water, but it is refusing to turn on your radiators because it cannot detect a request for central heating.
Your boiler is providing central heating as expected, but it is failing to heat your domestic hot water, likely due to a sensor or valve getting stuck in the wrong position.
Your boiler has lost all power and the screen is completely blank, meaning it is currently unable to operate.
Your boiler's air circulation system is not working, which means the unit cannot safely turn on to provide heating or hot water.
Your boiler has successfully ignited but is struggling to stay lit, so it has shut down as a precaution to prevent unburnt gas from accumulating.
Your boiler has detected a signal that a flame is present when it shouldn't be, which is a safety lockout preventing it from lighting.
Your boiler's temperature sensor is providing incorrect readings, so the system has shut down to prevent overheating while it waits for a professional to confirm the temperature.
Your boiler has detected that the hot water pipes entering and exiting the unit have been installed the wrong way around, preventing the system from circulating heat safely.
Your boiler has detected that the electricity coming from your home's mains supply is higher than it is designed to handle, which is causing it to shut down to prevent internal electrical damage.
Your boiler has tried to start five times but failed to ignite, so it has safely shut itself down to prevent a build-up of unburnt gas.
Your boiler is struggling because the electricity supply from your home to the unit has dropped below the required level for it to operate safely.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has lost the connection to the weather sensor outside, so it is currently relying on default internal settings rather than adjusting your heating based on the temperature outdoors.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage.
Your boiler’s main control computer is malfunctioning, which means the device cannot safely operate and has shut itself down to prevent further issues.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent potential overheating.
Your boiler is not receiving the correct signal from your wall thermostat, so it has stopped heating your home to prevent an incorrect temperature.
Your boiler's computer has recently been replaced but hasn't been programmed with the specific settings required to operate your model.
Your boiler has attempted to restart itself multiple times in a short window because it keeps encountering a recurring problem, and it has now locked itself out to prevent damage.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes