51 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that the exhaust gases are getting too hot and has automatically shut itself down to prevent damage or safety issues.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler is failing to light the flame, which means it cannot produce any heat or hot water for your home.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage to the system.
Your boiler is failing to light the burner, meaning it cannot produce heat or hot water because it has lost the ability to detect or maintain a stable flame.
Your boiler is struggling to move water through your heating system, which is preventing it from heating up your home or water properly.
Your boiler is struggling to accurately measure the temperature of the water being stored for your taps and showers.
Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage.
Your boiler is struggling to circulate water properly because there is too large a temperature difference between the water leaving and returning to the boiler.
Your boiler has attempted to start several times but failed, so it has locked itself for safety to prevent any potential issues.
Your boiler is failing to light or stay lit, so it has safely shut itself down to prevent gas from building up.
Your boiler is failing to light the flame after several attempts, so it has shut itself down to prevent a gas buildup.
Your boiler is failing to start because it cannot detect the expected temperature rise when it tries to fire up.
Your boiler has detected a fault in the system that controls the flow of gas, meaning it cannot safely ignite to provide heating or hot water.
Your boiler is failing to light the flame properly during start-up, so it has turned itself off for safety.
Your boiler has stopped working because it is struggling to ignite or maintain a stable flame during the combustion process.
Your boiler has detected an internal communication error with the mechanism that controls the gas supply, meaning it has safely shut itself down to prevent operation with a potential fault.
Your boiler has detected an electrical issue with the internal component that controls the gas supply, meaning it has safely shut itself down to prevent any risk.
Your boiler is temporarily limiting its performance because it has detected a reading that suggests the air mixture is not quite right, often triggered by flue conditions or pressure changes.
Your boiler's computer is struggling to start up correctly, which has caused it to stop working to prevent any potential damage.
Your boiler has encountered a general internal system error that it cannot automatically resolve, and it requires a professional reset or diagnostic check.
Your boiler has too much water in the system, causing it to shut down to prevent damage from excessive pressure.
Your boiler has lost the ability to measure the temperature of your tap water, meaning you will likely have no hot water until the sensor is fixed.
Your boiler has lost its connection to the sensor that monitors the heating temperature, causing the system to stop running to prevent damage.
Your boiler is struggling to accurately read the temperature of the water returning to it, so it has stopped working to prevent potential damage.
Your boiler is unable to control the gas flow properly because of a communication fault between its brain and the gas valve.
Your boiler has shut down because the internal exhaust gases have reached a dangerously high temperature, triggered by a safety sensor.
Your boiler has detected that the sensor monitoring the temperature of the exhaust fumes is sending an incorrect signal or has failed.
Your boiler has detected a problem with the fan that clears exhaust gases, preventing the unit from starting safely.
Your boiler has detected a fault with a secondary temperature sensor that monitors water returning to the unit, causing it to stop operating for safety.
Your boiler has detected that water is not moving through the system correctly, causing a temperature imbalance that has shut the unit down for safety.
Your boiler is struggling to detect the flow of water, which means it cannot tell if the taps are running or if it needs to heat your home.
Your boiler has detected that the electrical supply coming into the unit is too weak for it to run safely.
Your boiler has detected an issue with the stability of the electrical power supply coming into your home.
One of the buttons on your boiler's control panel has become stuck or is malfunctioning, preventing you from changing settings.
Your boiler has lost its connection to your room thermostat, meaning it cannot receive instructions on when to turn the heating on.
Your boiler has lost its settings and doesn't know how to burn gas efficiently, so it has shut down as a safety precaution.
Your boiler has stopped working because it cannot correctly measure the temperature of the water inside the system.
Your boiler has detected an issue with its internal combustion levels and cannot regulate the gas flame safely.
Your boiler has reached its safety limit for monitoring the gas flame and cannot adjust itself correctly to heat your home.
Your boiler is struggling to maintain its lowest flame setting, which is preventing it from running safely and efficiently.
Your boiler has detected an inconsistent flame, which is often caused by a temporary interruption in the gas supply or a slight blockage in the air vent.
Your boiler is slowing down its performance because it has detected that the gas pressure coming into the unit is too low to run at full power.
Your boiler has stopped working because it cannot detect a stable flame, often due to a problem with the gas supply or a faulty internal sensor.
Your boiler has detected an issue with how it mixes fuel and air for combustion, meaning it cannot operate safely or efficiently.
Your boiler has detected that wind or air pressure outside is affecting the way the gas burns, and it needs a professional check to ensure it is operating safely.
Your boiler is struggling to control its flame correctly and has shut down as a safety precaution.
Your boiler is struggling to maintain a steady flame because it either isn't receiving enough gas or it is drawing in its own exhaust fumes.
Your boiler is struggling to maintain a steady flame, which is likely caused by a loose connection or a dirty component inside the burner unit.
Your boiler has detected an issue with how exhaust gases are leaving the flue or a problem with the air-fuel mixture, causing it to shut down for safety.
Your boiler is struggling to ignite the gas properly and has locked itself out for safety after several failed attempts.
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BoilerFaultCodes