59 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water until the issue is resolved.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage.
Your boiler has detected that the exhaust gases leaving the unit are dangerously hot, so it has safely shut itself down to prevent damage.
Your boiler has lost the secure electrical connection required to safely control its internal gas supply, preventing it from firing up.
Your boiler is struggling to detect the flow of water through the pipes because a sensor is sending an incorrect electrical signal.
Your boiler is struggling to accurately measure the temperature of the hot water it is attempting to heat for your taps and shower.
Your boiler is currently in a manual testing mode used by engineers to check its performance, which is why it is showing this code on your remote controller.
Your boiler has attempted to restart itself too many times after a fault and has now locked itself out for safety, so it will no longer fire up.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to detect the temperature of your hot water cylinder, which means it may fail to heat your water properly.
Your boiler's computer has detected a conflict between its internal programming and how the plumbing system is actually set up.
Your boiler has stopped working because it cannot communicate with the internal fan that clears exhaust gases from the system.
Your boiler has detected heat or fire inside the unit even when it hasn't turned the gas on, so it has shut down to keep your home safe.
Your boiler's temperature gauge is misreading, which prevents it from heating your home because it doesn't know the current temperature of the water returning to the system.
Your boiler's control panel detects that one of the buttons is jammed or being held down permanently, which is stopping the system from operating normally.
Your boiler's computer is experiencing a temporary glitch that is preventing it from starting up or operating correctly.
Your boiler is struggling to pump water around your heating system effectively, causing it to shut down to prevent damage from overheating.
Your boiler has detected a faulty reading from the temperature sensor measuring your exhaust gases, so it has safely shut down to prevent potential overheating.
Your boiler has lost its digital connection to your room thermostat, meaning it no longer knows when to turn the heating on or off.
Your boiler is failing to start because it isn't receiving enough electricity from your home's power supply.
Your boiler is struggling to keep the flame lit and is automatically trying to restart itself to get your heating or hot water working again.
Your boiler is struggling to keep its internal flame lit and has safely shut down to prevent any issues.
Your boiler is struggling to move water through the system efficiently, causing it to overheat very quickly.
Your boiler has lost the connection to your room thermostat, meaning it doesn't know when to turn your heating on or off.
Your boiler is running too hot and has automatically lowered its performance to protect itself from heat damage.
Your boiler is shutting itself down because the water returning from your radiators is getting far too hot, which suggests an issue with water flow or a faulty sensor.
Your boiler is struggling to talk to your wireless thermostat, meaning it doesn't know when to turn your heating on or off.
Your boiler's water circulation pump has stopped working, meaning the unit cannot move hot water around your home and has shut down to protect itself.
Your boiler is struggling because there is air trapped inside the system, preventing water from flowing through your radiators properly.
Your boiler is struggling to accurately detect its own internal temperature, which is preventing it from heating your home or water reliably.
Your boiler is failing to heat the water inside it, so it has shut down to prevent damage while it fails to warm up your radiators or taps.
Your boiler is struggling to accurately monitor the temperature of the water circulating through your heating system, so it has stopped working as a safety precaution.
Your boiler is currently unable to read the water temperature correctly, so it has shut down as a precaution to prevent overheating.
Your boiler is trying to start up but cannot light the internal flame needed to heat your water.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal parts.
Your boiler has detected that the flue gases are becoming too hot, so it has safely shut itself down to prevent any damage.
Your boiler is currently unable to read the temperature of the water flowing to your radiators, so it has shut down to prevent potential overheating.
Your boiler is struggling to accurately measure the temperature of your hot water, which means the system may stop producing hot water until the faulty sensor is replaced.
Your boiler has failed to light the flame after several attempts and has safely locked itself to prevent gas buildup.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has stopped because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has lost the ability to read the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler has detected that the internal air circulation system is not working correctly, so it has safely shut down to prevent unsafe operation.
Your boiler has detected a flame inside when it should be turned off, which prevents it from starting up safely.
Your boiler's control panel is not responding correctly, which is preventing the system from starting up or adjusting its settings.
Your boiler has lost its digital connection to your room thermostat or remote control unit, preventing it from receiving instructions to start heating.
Your boiler has detected a flame inside when it should be turned off, which is a significant safety precaution that causes the system to shut down to prevent potential gas build-up.
Your boiler has detected that the electricity coming from your home's main supply is weaker than necessary to run safely.
Your boiler has stopped working because it cannot detect a flame, meaning it is currently unable to safely heat your home or water.
Your boiler is failing to stay lit because it cannot consistently detect the flame, meaning you currently have no heating or hot water.
Your boiler's internal fuel control system is experiencing an electrical measurement error, causing it to shut down for safety reasons.
Your boiler has detected an electrical issue with the part that controls the gas supply, meaning it has safely shut itself down to prevent any risk.
Your boiler is struggling to send enough power to the gas valve, which prevents it from safely igniting the fuel needed to heat your home.
Your boiler has detected an internal fault with the component that controls your gas supply, meaning it has safely shut down to prevent unsafe operation.
Your boiler has detected that the exhaust pipe used to vent gases outside is blocked, preventing it from operating safely.
Your boiler is simply reminding you that it is time for its annual safety service to keep it running efficiently and safely.
Your boiler is currently in a manual testing mode used by engineers to check the system, which is normal and not a malfunction.
Your boiler has lost its electronic link to the remote temperature controller, meaning it can no longer receive instructions on when to turn the heating on or off.
Your boiler is reminding you that it is time for its annual safety check and routine maintenance service.
BoilerFaultCodes