74 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's control panel is experiencing a communication error, which means it cannot process commands or display information correctly.
Your boiler has lost the ability to read the temperature of the water circulating through your heating system, so it has shut itself down to prevent it from overheating.
Your boiler has lost the ability to measure the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of the water used for your heating, so it has shut down to prevent any damage.
Your boiler has lost the ability to accurately measure the temperature of the water coming back into it, so it has shut down to prevent overheating.
Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage to its internal systems.
Your boiler has stopped working because the water pressure inside the system is too low.
Your boiler has detected that the water flowing out is significantly hotter than the water returning, suggesting a poor flow through your heating system.
Your boiler is struggling to move water around your heating system correctly, which is causing it to shut down to prevent overheating.
Your boiler is unable to regulate its gas flow correctly, which is preventing it from lighting safely.
Your boiler is failing to detect a flame, so it has safely shut itself down to prevent gas from building up.
Your boiler is trying to start but cannot light the flame, which means you currently have no heating or hot water.
Your boiler has stopped because the flame inside has gone out and will not stay lit.
Your boiler is struggling to breathe properly because it cannot pull in enough fresh air to safely burn the gas, so it has shut down to prevent any risk.
Your boiler is struggling to communicate with its internal controls due to a problem with the electrical signal it uses to coordinate its functions.
Your boiler has detected an internal electrical problem that is preventing it from safely controlling the gas supply, so it has shut down to keep you safe.
Your boiler has detected an issue with the valve that controls the gas supply and has safely shut itself down to prevent any risk.
Your boiler’s internal computer has encountered a critical storage error and can no longer safely control your heating or hot water.
Your boiler is struggling because it is detecting confusing and jumpy temperature readings, causing it to shut down to prevent damage.
Your boiler has detected that its internal control unit is getting too hot, so it has safely shut itself down to prevent damage.
Your boiler has stopped working because it cannot detect the flame used to heat your water.
Your boiler is struggling to maintain a steady flame, causing it to shut down to stay safe.
Your boiler's electronic control panel is not communicating correctly with the main internal computer, causing the system to lock out for safety.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water being sent to your radiators, causing it to shut down for safety.
Your boiler has detected that the water inside the unit is not circulating properly, so it has stopped working to protect itself from overheating.
Your boiler is struggling to accurately detect the water pressure in your heating system, so it has safely shut down to prevent potential damage.
Your boiler is struggling to read the water pressure in your heating system, which is preventing it from firing up reliably.
Your boiler has detected a safety-related overheating issue and has shut itself down to prevent any damage or danger.
Your boiler has detected an issue with the valve that controls the supply of gas to the burner, meaning it has safely shut itself down and will not provide heating or hot water.
Your boiler has detected that there is not enough water circulating inside the system to carry the heat away safely, so it has turned itself off to prevent damage.
Your boiler has detected an imbalance in the water temperature flowing in and out of the heating system, causing it to shut down to prevent potential damage.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating through your heating system.
Your boiler has detected an issue with the connection to your underfloor heating system, which prevents the boiler from communicating correctly with that circuit.
Your boiler is currently in standby mode because it has not received a signal from your thermostat or timer to turn on the heating.
Your boiler is currently performing a routine startup check of its internal ventilation system before it begins to heat your home.
Your boiler is currently checking the water circulation pump before it fires up, which is a standard part of its startup process.
Your boiler is failing to light the flame needed to provide you with heating or hot water.
Your boiler is operating normally and the burner is currently lit, meaning it is successfully heating your water or radiators.
Your boiler is currently running its cooling cycle after being turned off, which is a normal part of its operation to prevent overheating.
Your boiler is currently running its internal fan to clear any leftover air or gases after a heating cycle, which is a normal part of the shutdown process.
Your boiler is simply performing a routine cooling cycle to move hot water away from the heat exchanger, which is a normal part of its shutdown process.
Your boiler is perfectly fine and is simply taking a short, programmed break to prevent it from switching on and off too frequently.
Your boiler is simply currently running to provide hot water to your taps or shower, and this is a normal operating status rather than a fault.
Your boiler is performing a routine safety check by starting the internal ventilation fan before the burner ignites.
Your boiler is failing to light the flame properly, so it has safely shut itself down to prevent a gas buildup.
Your boiler is operating correctly and is currently firing up to heat your water or home.
Your boiler is currently running its internal cooling process to safely clear out residual heat after the heater has finished its cycle.
Your boiler is simply running its fan for a short time after you have turned off your heating or hot water to safely clear any leftover gases from the unit.
Your boiler is simply performing a routine cooling process to move leftover hot water out of the system after the heating or hot water has switched off.
Your boiler is currently checking its internal water pump to ensure everything is ready to safely start heating your home.
Your boiler is currently performing a routine start-up check of its air extraction system to ensure it is safe to ignite.
Your boiler is failing to light the internal flame needed to produce heat or hot water.
Your boiler is operating normally and the burner is currently lit, meaning it is successfully heating your water or radiators.
Your boiler is currently cooling down its internal components, which is a normal part of its shutdown process after heating or hot water usage.
Your boiler is simply finishing its cooling cycle to safely clear leftover gases after the burner has turned off.
Your boiler is simply moving water around the system for a few minutes after the heating has turned off to make sure the leftover heat is safely cleared.
Your boiler has temporarily stopped heating your hot water cylinder because it has reached its safety limit after a long heating session.
Your boiler is currently in standby mode because it is not receiving any instructions from your thermostat or hot water tap to start heating up.
Your boiler is currently set to only provide hot water and will not heat your radiators.
Your boiler is struggling to get the internal fan spinning at the right speed to safely clear exhaust gases, so it has stopped working as a safety precaution.
Your boiler has detected that the external temperature is very low and has automatically turned itself on to heat the pipework and prevent it from freezing.
Your boiler's fan, which is essential for safely removing exhaust gases, is failing to spin at the correct speed to operate properly.
Your boiler has detected that water is not circulating properly around your heating system, likely due to a blockage in the pipes or a stuck valve.
Your boiler is struggling to push air through the system correctly, which is preventing it from heating your home safely.
Your boiler has detected that the water pressure inside the system is currently too high for it to operate safely.
Your boiler has temporarily held back its output because it senses that water is moving too slowly or cooling down too quickly between the heating pipes.
Your boiler has paused because either the water pressure in your system is too low or the water is not circulating properly between your radiators and the boiler.
Your boiler is temporarily running at a fixed heat setting because it has detected an unusual operating condition it needs to manage.
Your boiler is currently running a series of automated self-check tests and is not experiencing a fault.
Your boiler has detected that water is not flowing through the system as expected, which means it has switched itself off to prevent internal damage.
Your boiler has detected an electrical issue that is forcing it to stop working for safety reasons to prevent further internal damage.
Your boiler is struggling to accurately measure the temperature of the water returning to it, meaning it cannot properly regulate your heating or hot water.
Your boiler has detected that the water pressure sensor is not working properly, which has triggered a safety shutdown to prevent damage to the system.
Your boiler has detected that water is not circulating properly through the system, meaning it cannot provide heating or hot water safely.
BoilerFaultCodes