126 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Heatline Capriz
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Your boiler is struggling to detect if water is moving through the system, which is preventing it from heating up your radiators or taps.
Your boiler's electronic brain is experiencing a critical internal failure and is unable to safely control the system.
Your boiler is struggling to detect the flow of water because it is having trouble reading the internal pressure levels correctly.
Your boiler is struggling to detect the flow of water because its internal sensor is faulty, which is preventing it from heating your home or water reliably.
Your boiler is struggling to detect the temperature of your hot water supply, so it has safely stopped heating to prevent potential issues.
Your boiler is currently unable to read the water temperature correctly, so it has shut down to prevent overheating while it waits for a repair.
Your boiler's water circulation device is not moving water effectively, which prevents your heating and hot water from working.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has detected a critical internal hardware fault with its main electronic control unit, preventing it from operating safely.
Your boiler has lost the ability to accurately measure the temperature of the water flowing through the system, so it has shut down to prevent damage.
Your boiler is not detecting water flowing through its pipes, which means it will stop heating your water or home to prevent damage.
Your boiler is failing to detect that water is circulating through the system, so it has shut down to prevent the internal components from overheating.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from firing up safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected an issue with the water circulation, meaning it has shut down to prevent internal damage or overheating.
Your boiler has detected an issue with the fan system that prevents it from safely exhausting air, causing the unit to shut down to protect itself.
Your boiler is failing to start up properly after multiple attempts.
Your boiler has detected an electrical issue where it is not receiving the correct voltage required to run its components safely.
Your boiler is experiencing a communication error between its internal electronic control systems, which is preventing it from operating correctly.
Your boiler is failing to monitor the exhaust fumes correctly due to a communication error with the fan or venting system, causing it to shut down for safety.
Your boiler is experiencing a communication error between its internal electronic parts, preventing it from operating correctly.
Your boiler is trying to start but the flame is failing to light, stopping your heating and hot water from working.
Your boiler has automatically shut down because it has detected that it is running too hot and needs to cool down to prevent damage.
Your boiler is struggling to clear exhaust gases safely, so it has shut down to prevent any risk of fumes entering your home.
Your boiler is failing to light the internal burner, so it has safely shut itself down to prevent a gas build-up.
Your boiler has stopped working because it cannot detect that the internal fan is moving air properly, which is a key safety requirement for the appliance to ignite.
Your boiler has lost the ability to read the temperature of the water being used for your heating, so it has shut down as a precaution to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the hot water it produces, so it has turned off the hot water supply to prevent overheating.
Your boiler has stopped working because it can no longer accurately read the temperature of the water used for your heating.
Your boiler is currently unable to read the temperature of the water returning to it, which means it has safely shut down to prevent overheating.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has detected that the water pressure inside your heating system is too high and is shutting down to prevent damage.
Your boiler is struggling to accurately detect the temperature of the water used for your taps and showers, so it has stopped heating them to prevent potential overheating.
Your boiler is struggling to read the outdoor temperature, so it has defaulted to a standard setting to ensure you still have heating and hot water.
Your boiler is failing to detect when you turn on the hot tap, meaning you are unlikely to get any hot water from your taps or shower.
Your boiler is struggling to control the internal gas flow correctly, which is preventing it from firing up or maintaining a consistent flame.
Your boiler's internal fan is failing to spin at the correct speed, which prevents it from safely venting gases and forces it to shut down for your protection.
Your boiler's internal fan is struggling to spin at the right speed, which means the unit has safely shut down to prevent unsafe combustion.
Your boiler is unable to move water around the system, meaning your heating and hot water will stop working until the internal pump is restored.
Your boiler is struggling because the temperature difference between the water leaving the boiler and the water returning to it is too high, meaning the system cannot circulate heat effectively.
Your boiler's computer system is experiencing a software communication error, preventing it from operating correctly.
Your boiler has detected that the water pressure inside the system is inconsistent, which is preventing it from heating your home reliably.
Your boiler's computer memory has become scrambled, preventing it from understanding its own settings and stopping it from working properly.
Your boiler's computer is struggling to read its own configuration settings, which is preventing it from starting up correctly.
Your boiler is struggling to clear exhaust gases effectively because the internal fan is not spinning fast enough, so it has safely shut down to prevent unsafe operation.
Your boiler has detected that heat is not moving away from the internal heating element efficiently, causing a sharp difference in temperature that has triggered a safety shutdown.
Your boiler has detected an internal electrical issue with the mechanism that controls the gas supply, meaning it has switched itself off for safety.
Your boiler has detected an issue with how the electrical supply is connected to its internal components, causing it to shut down for safety reasons.
Your boiler has detected an issue with the internal ventilation system that removes exhaust gases, so it has safely shut down to prevent unsafe operation.
Your boiler has detected that the exhaust gases cannot escape safely, so it has shut down to prevent the build-up of dangerous fumes inside your home.
Your boiler has detected that the flue exhaust is becoming dangerously hot and has shut itself down to prevent damage or safety hazards.
Your boiler's internal computer is struggling to talk to its control panel, meaning it has safely shut down to prevent incorrect operation.
Your boiler has detected an internal computer error which prevents it from operating safely.
Your boiler is failing to detect the correct air or gas pressure required to operate safely, so it has shut down to prevent any risk.
Your boiler has detected that the electricity supply coming into it is unstable or at the wrong voltage, causing it to shut down to protect its internal electronics.
Your boiler is detecting a flame inside even though it shouldn't be running, which suggests a safety component is failing to shut down correctly.
Your boiler has detected that a safety device or external control linked to the system has been triggered or disconnected, causing the unit to stop operating to remain safe.
Your boiler has detected that the electricity supply coming from your home's mains is below the level required for it to run safely and consistently.
Your boiler is struggling to talk to an optional outdoor temperature sensor, which may cause your heating to run less efficiently than usual.
Your boiler is receiving an confusing signal from a temperature sensor located outside your home, likely due to a loose wire or a faulty connection.
Your boiler has lost track of the water temperature coming back into the unit, so it has safely shut down to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of the water being sent to your radiators, so it has shut down to prevent damage.
Your boiler has lost the ability to accurately measure the temperature of the water used for your taps and shower, so it has switched off the hot water supply to prevent overheating.
Your boiler has lost signal from the temperature sensor on the outside of your house and is no longer able to automatically adjust its heating based on the weather.
Your boiler has detected an issue with the control mechanism that regulates the gas supply, meaning it is currently unable to start or maintain a flame safely.
Your boiler has detected that the internal water pump is stuck or blocked, meaning it cannot circulate heat to your radiators or taps.
Your boiler has lost the ability to accurately measure the temperature of the water being heated for your taps and shower, so it has shut down to prevent overheating.
Your boiler has lost its connection to the heat sensor, preventing it from knowing the temperature of the water and causing it to shut down for safety.
Your boiler's internal computer is having trouble talking to its own parts, which has caused it to shut down for safety.
Your boiler has detected an internal electrical problem with its main control unit, meaning it has safely shut down to prevent further damage.
Your boiler's water pump is failing to circulate water correctly, meaning the system cannot move heat to your radiators or taps.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not operating correctly, so it has shut down to prevent any risk of fumes entering your home.
Your boiler is unable to safely control the flow of gas required to light the burner, so it has shut down to prevent any risk.
Your boiler has detected an internal electronic error that is preventing it from operating safely, signalling that the main control system has encountered a critical fault.
Your boiler has detected that the internal fan responsible for safely venting fumes is not spinning at the correct speed, so it has shut down to prevent unsafe operation.
Your boiler has detected a problem with the internal mechanism that controls the gas supply, meaning it cannot safely start up to provide heating or hot water.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, which will likely result in the hot water not working correctly.
Your boiler is currently unable to determine how hot the water inside is circulating, so it has safely shut down to prevent overheating.
Your boiler has detected an issue with the internal electrical connections or a sensor signals a communication breakdown.
Your boiler has detected that it is overheating or that a safety sensor is misreading the temperature, causing it to shut down to prevent damage.
Your boiler's computer has encountered an internal communication error and has shut down to prevent incorrect operation.
Your boiler's temperature sensor is providing inconsistent readings, causing the system to stop working as a precaution.
Your boiler is struggling to read its own internal signals, likely due to a loose wire or a faulty electronic component, which has caused it to stop heating your home as a safety precaution.
Your boiler is having trouble communicating with its internal sensors, which means it cannot accurately monitor temperatures and has stopped working as a safety precaution.
Your boiler has failed to light the flame needed to produce heat or hot water, meaning it has safely shut itself down as a precaution.
Your boiler is failing to light the fuel inside to start the heating process, so it has shut down as a safety precaution.
Your boiler is struggling to detect if the internal fan is spinning correctly, which causes it to shut down for your safety to prevent the build-up of harmful exhaust gases.
Your boiler has detected an issue with the flame ignition process and has safely locked itself out to prevent fuel waste or unsafe operation.
Your boiler has detected an issue with the internal fan that pushes exhaust gases out of the flue, so it has shut down to keep your home safe.
Your boiler has reached its programmed service interval limit and currently requires a professional safety check by a qualified engineer.
Your boiler is struggling to read its own temperature because a sensor responsible for monitoring the heating water has likely failed or sent an incorrect signal.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water being sent to your radiators.
Your boiler is struggling to push air through its system correctly, so it has safely shut down to prevent any unsafe operation.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water inside it.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has shut down to prevent overheating.
Your boiler is struggling to accurately measure the temperature of your hot water, which means it will likely stop producing hot water until the faulty sensor is replaced.
Your boiler's temperature sensor is providing incorrect readings, which prevents the unit from starting your heating or hot water safely.
Your boiler's temperature sensor is providing incorrect readings, which means the system has safely shut down to prevent it from overheating.
Your boiler has detected an issue with the valve that controls the flow of gas, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has stopped working because it cannot confirm that the internal fan, which is essential for safely venting exhaust gases, is spinning at the correct speed.
Your boiler has detected an issue with its electrical power supply, preventing it from operating safely.
Your boiler has detected a general internal electrical or software glitch that is preventing it from operating safely.
Your boiler's main control unit has identified an internal electronic error and has shut down for safety to prevent system damage.
Your boiler is struggling to accurately measure the temperature of the hot water it provides, which may result in your tap water being inconsistently heated.
Your boiler is failing to ignite because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is failing to detect the flame correctly, so it has safely shut itself down to prevent gas from being released without burning.
Your boiler is failing to detect a flame when it tries to start, which prevents it from heating your home safely.
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 a communication error with its internal temperature sensors, causing the heating system to stop working as a safety precaution.
Your boiler's temperature sensor for hot water is reporting a fault, which means the domestic hot water system may stop heating up correctly.
Your boiler has detected that the fan mechanism responsible for expelling exhaust gases is not operating correctly, meaning it will remain safely shut down until checked.
Your boiler has lost the ability to detect the temperature of your hot water supply, so it has stopped heating it to prevent the system from overheating.
Your boiler has lost the ability to accurately measure the temperature of the water being heated for your taps and shower, so it has turned off the hot water to stay safe.
Your boiler has lost its connection to the external temperature sensor or the central heating thermostat, meaning it doesn't know when to turn the heating on or off.
Your boiler is struggling to communicate with your thermostat, meaning it doesn't know when to turn the heating on or off.
Your boiler has detected that the fan, which is essential for safely venting exhaust gases, is not operating correctly and has stopped working to prevent a safety risk.
Your boiler has detected that it is not receiving the correct amount of gas to operate safely and reliably.
Your boiler is failing to receive a consistent supply of gas, which is preventing it from igniting or staying lit.
Your boiler has developed a fault with the sensor that detects the temperature of your hot water, which means it may currently struggle to provide a consistent hot shower or tap supply.
Your boiler is struggling to accurately detect the temperature of your hot water, which may cause your taps to run cold or the water to fluctuate in temperature.
Your boiler is struggling to detect the temperature of the water coming out of your taps, which means it cannot reliably heat your hot water.
Your boiler is failing to light the flame properly, which means it cannot produce heating or hot water at the moment.
Your boiler is failing to light the flame properly, which means it cannot produce heating or hot water at the moment.
Your boiler is having trouble communicating with an optional outdoor temperature sensor, which may cause your heating to fluctuate or run less efficiently.
Your boiler is having trouble communicating with an outdoor weather sensor, which means it might not adjust its internal temperature settings correctly based on the outside air.
BoilerFaultCodes