94 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has temporarily shut down because a safety sensor detected that it is getting too hot inside.
Your boiler has tried to start up, but it cannot detect a flame to keep the burners alight, so it has shut down for your safety.
Your boiler has detected a false flame signal when the burner is not actually supposed to be lit, so it has safely locked out to prevent any risk.
Your boiler was running, but the flame went out unexpectedly, causing it to stop heating.
Your boiler has temporarily stopped working because an external safety switch, such as a smart thermostat or underfloor heating control, has locked the system.
Your boiler's internal computer is having trouble recognising a core internal part, so it has safely shut down to prevent any issues.
Your boiler has detected an electrical problem with the component that controls the gas supply, meaning it has safely shut down to prevent unsafe operation.
Your boiler is confused because its internal computer board and its identification settings do not match up correctly.
Your boiler has detected an internal system communication error and has safely shut down to prevent further issues.
Your boiler has detected an internal electronic failure within its main control system and has safely stopped working.
Your boiler has detected an internal electrical problem with its control system, which requires professional attention to resolve safely.
Your boiler has detected an internal electronic communication error and has safely shut down to protect its system.
Your boiler has detected an internal electronic or control board communication error and has safely shut down to protect itself.
Your boiler has detected an internal electronic communication error and has safely shut down to protect its system.
Your boiler has detected an internal electronic error within its main control board, causing it to shut down safely.
Your boiler has detected an internal electronic communication error, which means it has safely shut down to prevent any further issues.
Your boiler has detected an internal electronic or control board issue that requires attention.
Your boiler's main control computer has encountered an internal electronic error and needs to be reset or inspected by a professional.
Your boiler has registered an internal electronic system error, meaning it has safely shut down to prevent further issues.
Your boiler has detected an internal electronic or control system error that is stopping it from operating safely.
Your boiler has detected an internal electronic communication error, meaning it has safely shut down to protect its main control system.
Your boiler's main control system has detected an internal communication or electronic error and has safely shut down to prevent further issues.
Your boiler has detected an internal electronic error with its main control board, which has temporarily shut it down for safety.
Your boiler has detected an internal electronic communication or control board fault, which stops it from working safely.
Your boiler is temporarily pausing because it is producing more heat than your home is currently asking for.
Your boiler has run a routine internal safety check on its main electrical switches, but it needs an engineer to clear the code and check the internal control board.
Your boiler has temporarily stopped working because it cannot reliably detect or keep the burner flame lit.
Your boiler has temporarily stopped working because the flame and internal airflow were unexpectedly interrupted.
Your boiler has detected that water is not circulating properly through the system because the internal pump is either jammed or trapped air is blocking the flow.
Your boiler is simply preparing to ignite and fire up its burner as part of its normal heating cycle.
Your boiler has detected an issue with the internal valve that controls the precise mix of air and gas needed for safe, efficient burning.
Your boiler is temporarily pausing between hot water cycles to protect itself from overheating, which is a normal operation and usually resolves on its own.
Your boiler has detected that a flame is still present briefly after the gas supply has been shut off.
Your boiler is running a temporary ventilation check to clear any stale air from the system before it attempts to fire up safely.
Your boiler is automatically running a routine cycle to prevent the internal pump from getting stuck, which is a normal maintenance feature.
Your boiler has detected an internal electronic communication error, meaning it has temporarily stopped working for safety.
Your boiler's main electronic control system has experienced an internal communication failure and cannot identify its own components.
Your boiler has detected an internal electronic or control board error and has safely shut down to prevent damage.
Your boiler has temporarily stopped working because the main electronic control system has detected an internal safety fault and shut down.
Your boiler is receiving incorrect temperature readings because a sensor attached to a specialist heating component is failing, which may temporarily stop your heating system from working properly.
Your boiler's electronic control panel is currently unable to send or receive signals, causing the system to stop operating to prevent errors.
Your boiler's internal control parts have temporarily lost their ability to talk to each other, which stops the system from working.
Your boiler has detected that the burner is running at its maximum capacity for too long, causing it to proactively shut down to prevent overheating.
Your boiler has stopped working because the water pressure inside the system has dropped below the minimum level required to operate safely.
Your boiler is simply reminding you that it is due for its annual safety service.
Your boiler has identified that the internal water pump is not the correct type for this specific model, which is preventing the system from operating correctly.
Your boiler is struggling to accurately detect the temperature of your hot water, which means it may fail to heat your water or work inconsistently.
Your boiler has been running for a very long period without a break and has automatically paused to prevent overheating.
Your boiler is struggling to accurately monitor the temperature of the water returning to it, so it has stopped working to prevent potential overheating.
Your boiler has lost the connection to the weather sensor outside your home and is now running on a default setting to ensure you still have heating and hot water.
Your boiler is currently struggling to correctly measure the water pressure in your heating system, which prevents it from operating safely.
Your boiler's internal sensor system is confused about the air quality or external temperature, which may hinder its efficiency or ability to run.
Your boiler is simply reminding you that its annual service is due soon to keep it running safely and efficiently.
Your boiler is simply reminding you that it is time for its annual health check and service to keep it running efficiently and safely.
Your boiler is simply reminding you that it is time for its regular annual service to ensure it continues to run safely and efficiently.
Your boiler has stopped working because it thinks the internal heat sensor is damaged or has an electrical fault, preventing it from monitoring temperature safely.
Your boiler has stopped working because it can no longer communicate with the sensor that monitors the temperature of the main heating unit.
Your boiler has detected an internal software or electronic communication error that prevents it from operating safely.
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 an issue with the pipework that vents exhaust gases outside, meaning it has safely shut itself down to prevent any harmful fumes building up indoors.
Your boiler's computer is having trouble communicating with its internal systems, which has caused it to shut down for safety reasons.
Your boiler's main internal computer has encountered a memory or communication error, preventing the system from running safely.
Your boiler has detected an internal electrical communication error, meaning it cannot properly coordinate its functions to provide heat and hot water.
Your boiler has detected a problem with how it tracks its own flame, causing it to shut down for safety purposes.
Your boiler has detected an internal electrical communication error, which means it has stopped running to prevent damage to its electronic components.
Your boiler has detected an internal electrical problem that is preventing it from starting up safely.
Your boiler has detected a safety communication issue with the internal valve that controls the gas supply, meaning it has temporarily shut down to prevent any risk.
Your boiler has detected an unexpected electrical signal from its internal gas control component and has safely shut down.
Your boiler has detected an unexpected electrical signal from the internal gas control system and has safely shut down to prevent hazards.
Your boiler has tried to start up, but it cannot detect a steady flame to keep itself running safely.
Your boiler has detected an internal electronic error and has safely shut down to prevent further issues.
Your boiler's main computer has experienced an internal software error and has safely shut down to prevent incorrect operation.
Your boiler has detected that the electrical voltage supplying the internal burner control is too low, causing it to safely shut down to prevent damage.
Your boiler's computer brain has detected an internal electronic chip that doesn't match the model or has become loose.
Your boiler is struggling to stay lit when running at a low power level, which is preventing it from providing steady heating or hot water.
Your boiler is struggling to detect a flame when it tries to work at full power, meaning it cannot provide consistent heating or hot water.
Your boiler is trying to ignite but cannot detect a flame, meaning it is currently unable to provide heating or hot water for safety reasons.
Your boiler is repeatedly failing to keep its internal flame lit, so it has safely shut itself down to prevent gas from building up.
Your boiler has detected an internal error while trying to confirm it is burning fuel correctly, and it has shut down as a safety precaution.
Your boiler has detected an incorrect or incompatible internal configuration setting, which stops it from operating safely.
Your boiler's internal settings or water system configuration have not been properly recognized, which stops it from operating correctly.
Your boiler's internal electronic control system has identified a technical failure that requires an expert to reset or replace the faulty circuit board.
Your boiler has stopped working because it cannot confirm that the internal fan, which is essential for safely exhausting gases, is running correctly.
Your boiler has stopped working because the internal computer cannot communicate with the fan that clears exhaust gases.
Your boiler has stopped working because it is unable to accurately read the temperature of the water inside the unit.
Your boiler has shut down because the water circulating inside it is getting much hotter than it should perfectly safely be.
Your boiler is heating up too quickly because the water inside cannot flow away fast enough to cool the system down.
Your boiler has detected that the internal water pressure has dropped too low and needs to be topped up.
Your boiler's automatic filling system has topped up the water pressure too many times in a short period, suggesting there may be a leak in your heating system.
Your boiler has detected that water is escaping from your central heating system much faster than expected, which is preventing it from running properly.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler is struggling because the electricity coming into your home from the mains is weaker than the level required for it to operate safely.
Your boiler has gone into a secure lockout state and stopped working to protect itself, but it can usually be unlocked by pressing the control buttons.
Your boiler has temporarily locked itself as a safety precaution, but you can easily unlock the controls using the display buttons.
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BoilerFaultCodes