88 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start but is unable to light the flame needed to produce heat or hot water.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent any damage or safety risks.
Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has automatically shut itself down to prevent damage or safety hazards.
Your boiler has detected a faulty connection to the component that controls the gas supply, meaning it cannot safely turn on.
Your boiler is struggling to detect the temperature of the water flowing through your heating system, so it has turned itself off as a precaution.
Your boiler is having trouble accurately measuring the temperature of the water used for your taps and shower.
Your boiler has reached its safety limit for automatic restarts after repeated failures, meaning it has locked itself out to prevent further issues.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has lost the ability to accurately measure the temperature of your hot water tank, so it has stopped heating it to prevent overheating.
Your boiler's computer is confused because its internal settings do not match the signals it is receiving, preventing it from operating correctly.
Your boiler has stopped working because it cannot properly clear exhaust gases, which is a safety mechanism to prevent harmful fumes from building up.
Your boiler is confused because it thinks a flame is burning when it shouldn't be, or it cannot confirm the flame is lighting correctly, causing it to shut down for safety.
Your boiler has detected a communication error with a temperature sensor, which is preventing it from heating your home safely.
The boiler's control panel detects that one of the buttons is jammed, preventing it from functioning correctly.
Your boiler has detected an abnormally fast rise in temperature and has shut itself down to prevent internal damage.
Your boiler is struggling to pump water around your heating system fast enough, causing it to overheat and shut down for safety.
Your boiler has detected that the sensor monitoring the temperature of the gases leaving the flue is reading incorrectly, so it has safely shut down to prevent potential overheating.
Your boiler has lost its connection to its smart thermostat, meaning it cannot receive instructions on when to turn the heating or hot water on.
Your boiler is having trouble communicating with the temperature sensor for your secondary heating area, which may cause that part of your home to not heat up correctly.
Your boiler has detected that a secondary heating circuit, such as underfloor heating, has become too hot and has automatically shut down to prevent damage.
Your boiler has detected that a specific part of your heating system has reached a dangerously high temperature and has shut itself down to prevent damage.
Your boiler is displaying a communication error that shouldn't exist on this specific model, suggesting a temporary glitch in its internal computer system.
Your boiler is struggling because it is not receiving enough electricity from your home's power supply to run safely.
Your boiler is struggling to keep the flame alight once it has started, so it is automatically pausing to try again safely.
Your boiler is struggling to stay lit because the flame keeps going out, which can sometimes happen during very windy weather.
Your boiler has detected that the water leaving your heating system is returning much cooler than expected, suggesting a blockage or a failure to circulate heat properly.
Your boiler has detected an interruption in a safety circuit, likely caused by an external add-on like a frost protection sensor or safety thermostat being triggered or disconnected.
Your boiler has detected that the exhaust gases are getting too hot, so it is slowing down its performance to avoid damaging itself and to prevent a total shutdown.
Your boiler has lost its wireless connection to your room thermostat or controller, meaning it doesn't know when to turn your heating on or off.
Your boiler is struggling to read the electricity coming from your home's power supply, preventing it from starting up safely.
Your boiler has detected that the water pump responsible for circulating heat around your home is jammed or experiencing an electrical issue, meaning it cannot provide you with heating or hot water.
Your boiler is struggling because air bubbles are trapped inside the system, preventing the water from circulating properly to heat your home.
Your boiler has lost its specific operating settings and needs a professional engineer to electronically recalibrate it to ensure it is burning fuel safely and efficiently.
Your boiler's computer system has detected that some of its internal settings have drifted or been changed, and it needs a professional to recalibrate it to run correctly.
Your boiler has detected conflicting temperature readings between its internal sensors, leading it to shut down for safety reasons.
Your boiler has detected a faulty reading from an internal temperature sensor, causing it to shut down for safety reasons.
Your boiler has detected an issue with the internal component that controls the gas supply, meaning it has safely shut itself down to prevent unsafe operation.
Your boiler has detected an internal error with the mechanism that controls the fuel supply, meaning it has safely shut itself down to prevent unsafe operation.
Your boiler has detected an internal electrical problem that is preventing it from safely opening the gas supply, so it has shut down to protect your home.
Your boiler is not receiving enough gas to run at full power, so it has automatically limited its own performance to keep you safe.
Your boiler has detected an internal safety fault in the part that manages the gas supply, meaning it has shut down to prevent unsafe operation.
Your boiler is struggling to keep its internal flame lit steadily, so it has safely shut itself down to prevent any issues.
Your boiler has detected an abnormal reading from the flame sensor, meaning it cannot safely determine if the burner is operating correctly and has shut down as a precaution.
Your boiler is trying to start but failing to keep the flame lit, which means it has automatically shut down to stay safe.
Your boiler's fan is struggling to push air out as it should, meaning the unit has stopped working to keep you safe.
Your boiler has detected an issue with the flame sensor reading, meaning it cannot safely regulate the internal flame and has shut down to prevent damage.
Your boiler has detected a problem with burning fuel safely and has shut itself down to prevent any potential danger.
Your boiler is struggling to keep a steady flame, causing it to shut down because it cannot safely maintain the fire needed to heat your home.
Your boiler has detected a blockage in the ventilation system, meaning it cannot exhaust fumes safely and has shut down to prevent a hazard.
Your boiler's computer has encountered too many internal processing errors and has locked itself down as a safety precaution.
Your boiler has detected an issue with the internal water pressure or circulation flow, meaning it cannot safely heat your home or water.
Your boiler's internal pump is currently running at a fixed, constant speed rather than adjusting to the needs of your heating system.
Your boiler is receiving an unusual reading from an external weather-sensing device linked to your heating system, signaling that the correction value is set incorrectly.
Your boiler is failing to light the flame needed to heat your water and home.
Your boiler has detected that it is getting too hot and has automatically shut down to prevent any internal damage.
Your boiler has detected that the internal exhaust area is getting too hot and has automatically shut down for your safety.
Your boiler is struggling because it cannot detect enough water flowing through its internal system, which prevents it from safely heating your home.
Your boiler's temperature sensor is providing faulty readings, which has caused the system to stop heating for safety reasons.
Your boiler is struggling to accurately measure the temperature of the hot water it is producing, which will likely prevent you from having a consistent supply of hot water.
Your boiler has blocked itself from being restarted because it has detected a recurring fault that you have tried to reset too many times.
Your boiler has lost its connection to the component that controls gas flow, meaning it cannot ignite safely and has shut down to protect your home.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler's computer has lost its internal settings, meaning it no longer knows how to operate correctly and has locked itself for safety.
Your boiler has detected an issue with the internal fan that pushes exhaust gases out of your home, so it has safely shut down to prevent unsafe operation.
Your boiler has stopped heating because it is struggling to keep the flame lit, which means you currently have no heating or hot water.
Your boiler's control panel is experiencing a communication fault, meaning it cannot properly process your button presses or display the correct settings.
Your boiler is struggling to move enough water through its system, meaning it has switched off to protect itself until the flow is corrected.
Your boiler has lost its connection to the digital wall thermostat, meaning it no longer knows when to turn the heating on or off.
Your boiler has detected that the incoming electricity supply is too low for it to operate safely and has shut down to protect itself.
Your boiler has stopped working because it cannot maintain a stable flame, meaning it is currently unable to provide you with heating or hot water.
Your boiler has tried to light the burner several times but keeps failing, so it has safely shut itself down to prevent wasting gas.
Your boiler has lost its internal settings regarding the type of fuel it uses and requires a professional engineer to perform a re-calibration to function safely.
Your boiler has lost its fine-tuned settings and needs to recalibrate its internal systems to function correctly again.
Your boiler has detected an internal electrical issue with the mechanism that controls the gas supply, meaning it has shut down as a precaution to keep your home safe.
Your boiler is struggling to send the necessary electrical signal to its internal gas control system, meaning it cannot ignite or maintain a flame safely.
Your boiler is struggling because the water inside is not circulating properly, causing a significant temperature difference between the water leaving and returning to the unit.
Your boiler's computer is experiencing an internal error, which means the system has stopped working as a safety precaution.
Your boiler has detected an obstruction in the pipe that expels waste gases, causing it to shut down to prevent the buildup of dangerous fumes indoors.
Your boiler is currently in a manual testing mode used by engineers to check exhaust emissions, so it is not actually broken.
Your boiler has automatically activated its internal heater to protect itself from freezing during cold weather.
Your boiler is simply performing a routine safety clear-out to remove any remaining exhaust gases after finishing a heating or hot water cycle.
Your boiler is simply cooling itself down after use, which is a normal part of its automatic shutdown process.
Your boiler is currently running an automated 18-hour maintenance cycle to remove trapped air bubbles from your heating system, and you should simply wait for this process to complete.
Your boiler has stopped circulating water because a critical internal component is stuck, meaning you currently have no heating or hot water.
Your boiler is currently in a manual setup mode for output adjustments rather than reporting a functional breakdown.
Your boiler is currently set to a specific operational mode that balances water flow and energy use, which is normal behavior rather than a fault.
Your boiler is failing to switch off when the house reaches the target temperature, meaning your radiators will stay on until you manually turn the boiler down.
Your boiler has blocked itself from restarting due to too many failed attempts and needs to remain off for an hour before it will let you try again.
BoilerFaultCodes