33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost its connection to the gas valve, meaning it cannot ignite safely and has stopped providing heating or hot water.
Your boiler's outside temperature sensor has developed a fault or lost its connection, which might make your heating less efficient.
Your boiler has detected that water is not circulating correctly through the system, preventing it from heating up safely.
Your boiler has detected that a internal sensor is stuck, making the system think water is moving when it should be at rest.
Your boiler has detected an internal communication error with the part that controls the gas supply, meaning it cannot ignite safely to provide heat or hot water.
Your boiler's internal temperature sensor has developed a fault, meaning the system cannot correctly monitor the heat of your radiators and has shut down as a precaution.
Your boiler has detected a problem with the internal sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning from your radiators.
Your boiler is having trouble measuring the temperature of your hot water, which usually means it won't be able to provide reliable hot water to your taps.
Your boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
Your boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
Your boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
Your boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
Your boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
Your boiler is struggling to move water around the system before it starts the ignition process, which is preventing it from firing up.
Your boiler has shut down because it has detected it is getting too hot too quickly, usually caused by poor water circulation or trapped air.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that hot water isn't moving through the system properly, which is likely caused by a blockage or a pump issue.
Your boiler is struggling to keep its burner lit and has shut down after multiple failed attempts to maintain a flame.
Your boiler is struggling to keep a steady flame alight and has failed to automatically adjust itself after several attempts.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot, which is a safety feature to prevent damage.
Your boiler has failed to ignite, meaning it cannot light the gas to provide heating or hot water, often due to a lack of gas flow or a blocked condensate pipe.
Your boiler is struggling to light because it cannot detect a steady supply of gas or a flame within the required timeframe.
Your boiler has lost its connection to the gas supply due to an internal electronic communication failure, meaning it cannot ignite to provide heat or hot water.
Your boiler has detected that the water is circulating or heating up incorrectly, likely due to a pump issue or a blockage.
Your boiler has detected a problem with the fan that clears exhaust gases, preventing it from starting up for safety reasons.
Your boiler has detected a problem with the sensor that monitors hot water temperature, meaning you likely have no hot water or the temperature is inconsistent.
Your boiler has sensed it is getting too hot too quickly, likely because water isn't moving through the system properly.
Your boiler has detected an issue with the electrical power supply coming into your home, meaning the electrical frequency is not compatible with the boiler's electronics.
Your boiler has a faulty temperature sensor responsible for tracking the heat of your tap water, which usually results in inconsistent or no hot water.
Your boiler thinks a flame is present when there shouldn't be one, which stops it from starting up correctly for safety reasons.
Your boiler is not receiving enough electrical power to run safely and has shut down to protect its internal components.
Your boiler has detected a sudden drop or change in water pressure and has temporarily paused to re-check the system levels.
BoilerFaultCodes