74 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Heatline Capriz
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Your boiler's electronic display panel is failing to communicate with the internal system, which means the boiler cannot operate or respond to your commands.
Your boiler has lost the ability to measure the temperature of the water being sent to your radiators, so it has shut down as a precaution to prevent overheating.
Your boiler is failing to light because it cannot detect a flame or is not receiving a steady gas supply.
Your boiler is struggling to circulate water properly, which stops your heating and hot water from working correctly.
Your boiler has lost the ability to measure the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage to its internal components.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected that the water is not circulating properly, meaning it is getting hot in one area but not moving to the rest of your system fast enough.
Your boiler is struggling to move water around the system fast enough, likely due to low water pressure or a blockage.
Your boiler has detected a problem with the internal part that controls the flow of gas, meaning it cannot safely start up to provide heat or hot water.
Your boiler is failing to detect a flame, so it has purposefully shut down to prevent gas from building up inside the system.
Your boiler is trying to start but the flame is not catching, meaning it cannot provide you with heating or hot water.
Your boiler has stopped because the internal flame keeps going out while it is trying to heat your water or home.
Your boiler is struggling to push air through its system properly, which has caused it to stop working to keep you safe.
Your boiler has lost the communication signal between the main controller and the heating system, meaning it cannot receive instructions to provide heat or hot water.
Your boiler's electronic control centre has detected a critical internal error and has shut down to prevent damage or unsafe operation.
Your boiler has detected an issue with its internal gas supply system and has safely shut itself down to prevent any unsafe operation.
Your boiler's internal computer has encountered a critical memory error and can no longer safely control the heating system, requiring professional attention.
Your boiler is struggling to accurately read the water temperature, causing it to shut down for safety because the readings are changing too quickly.
Your boiler has detected that its internal computer has become dangerously hot and has shut itself down to prevent fire or electrical damage.
Your boiler has detected an issue with the flame detection system, meaning it cannot confirm that the burner is safely lit and will refuse to operate as a precaution.
Your boiler is struggling to keep a steady flame, causing it to shut down for safety reasons.
Your boiler's electronic control panel is not communicating correctly with the main internal computer, which prevents the system from starting up safely.
Your boiler has lost the ability to accurately measure the temperature of the water used for your radiators, causing it to shut down for safety reasons.
Your boiler has detected an unusual temperature gap between the outgoing and incoming water, indicating the system is struggling to circulate heat correctly.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from safely starting up your heating.
Your boiler's sensor is struggling to read your heating system's pressure, which prevents the unit from starting the heating or hot water safely.
Your boiler has detected an internal issue with a safety device designed to shut the system down if it gets too hot, and it will no longer operate until this is inspected.
Your boiler has detected an issue with the internal component that controls the gas supply, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has detected that there is not enough water pressure inside the system for it to heat your home safely.
Your boiler is confused because its temperature sensors are giving conflicting readings or are not properly connected, causing it to stop heating your home to prevent potential damage.
Your boiler's temperature sensors are reporting conflicting information because they are detecting heat from the same spot, causing the system to stop heating for safety.
Your boiler has lost the signal from the sensor that monitors your underfloor heating system, preventing it from activating those circuits.
Your boiler is currently in standby mode because it has not received a signal from your thermostat to turn on the heating.
Your boiler is currently performing a required safety check by running its internal fan before attempting to light the flame.
Your boiler is currently performing a routine internal check to ensure water is circulating properly before it attempts to fire up the burner.
Your boiler is failing to light the flame needed to produce heat or hot water.
Your boiler is operating normally and the burner has successfully ignited to provide heat or hot water.
Your boiler is currently cooling down by running its internal components to clear heat, which is a normal part of the shutdown process.
Your boiler is currently running its internal fan to safely vent any remaining gases after the burner has turned off, which is a normal part of the shutdown process.
Your boiler is simply performing a routine safety cycle where the pump continues to run for a short time after heating to distribute residual warmth.
Your boiler is currently taking a temporary rest pause between heating cycles to prevent excessive wear and tear, which is a normal part of its operation.
Your boiler is simply working as intended and is currently heating up water for your taps or shower.
Your boiler is currently preparing to ignite, but the internal fan is checking its position before the system starts burning fuel.
Your boiler is failing to light the flame, so it has safely stopped operating to prevent gas from building up inside.
Your boiler is operating normally—this code simply indicates that the burner is currently lit and heating your water.
Your boiler is currently performing a standard cool-down process after your heating or hot water has been running.
Your boiler is simply performing a routine safety process where the fan runs for a short time after the heating switches off to clear any leftover gases safely.
Your boiler is simply performing a routine safety cycle to circulate leftover heat away from the system, and no action is required.
Your boiler is currently preparing to fire by checking the water circulation, which is a normal part of the start-up process.
Your boiler is currently checking that its internal air extraction system is working correctly before it attempts to ignite the flame.
Your boiler is failing to light the flame properly, meaning it cannot provide you with heating or hot water.
Your boiler is operating normally and the burner is currently lit to provide heat or hot water.
Your boiler is currently cooling down its internal components after finishing a heating or hot water cycle, which is a normal part of the shutdown process.
Your boiler is simply finishing its cooling cycle after being in use, which is a normal part of its operation.
Your boiler is simply finishing a final water circulation cycle to safely cool itself down after heating has been running.
Your boiler has temporarily stopped heating your hot water cylinder because it has reached a protective safety limit meant to prevent the system from overheating.
Your boiler is currently in standby mode because it hasn't received a signal from your thermostat or hot water tap to start heating.
Your boiler is currently set to only provide hot water and is ignoring requests for central heating.
Your boiler is struggling to operate its internal fan correctly, which is preventing it from safely lighting and heating your home.
Your boiler has detected very low temperatures and is automatically firing up to protect its internal pipework from freezing.
Your boiler is having trouble managing the airflow needed to operate safely and has shut down to prevent any issues.
Your boiler has detected that water is not circulating properly through the heating system, which is preventing it from distributing warmth to your radiators.
Your boiler has detected that the internal fan responsible for safely venting fumes is not spinning at the correct speed to run efficiently.
Your boiler's internal water pressure is currently too high, which prevents it from operating safely to protect the system.
Your boiler has paused its heating process because the water circulating through your radiators is not returning to the unit quickly enough, often due to a blockage or restricted flow.
Your boiler has temporarily stopped heating because the water is not flowing through the system correctly, likely due to low water pressure or an airlock.
Your boiler is temporarily running at a restricted, pre-set power level to protect itself, rather than adjusting its heat output normally.
Your boiler is currently performing a mandatory internal self-check sequence and is not indicating a fault.
Your boiler has detected that water is not flowing through the system correctly, which is preventing it from heating your home or your water.
Your boiler has detected an electrical power problem that is preventing it from safely heating your home or water.
Your boiler has detected that hot water cannot circulate properly through the system, so it has safely shut down to prevent overheating.
Your boiler has detected that the water pressure sensor is not providing a signal, which prevents the heating and hot water from turning on.
Your boiler has detected that hot water cannot flow through the pipes properly, which has caused it to stop working for your radiators and taps.
BoilerFaultCodes