19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost communication with the sensor that measures the temperature outside, which may cause your heating to behave unpredictably.
Your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot safely regulate heat.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning from your radiators, preventing it from heating your home safely.
Your boiler has detected a problem with the sensor that manages your hot water, which means it cannot accurately tell if the water is at the right temperature.
Your boiler has lost the ability to communicate with its internal control systems or the external thermostat, meaning it cannot receive instructions to heat your home.
Your boiler has detected that the water pressure is either too low or too high, or the sensor that monitors this pressure has lost its connection.
Your boiler is busy removing air bubbles from the pipes after the water pressure was topped up, and it will return to normal operation in about seven minutes.
Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit, which has caused it to stop running for safety.
Your boiler has detected an issue with the sensor that monitors water returning from your radiators, preventing it from heating your home safely.
Your boiler's internal computer brain has temporarily lost its ability to talk to the control sensors and requires a manual power restart.
Your boiler has detected that water is not circulating properly, which could mean the pump has stopped working or the water pressure is too low.
Your boiler is currently running an automatic cycle to clear trapped air from the system, which typically occurs after it has been powered on or refilled.
Your boiler has switched itself off because it has become too hot internally, often due to a lack of water flow or a blockage.
Your boiler has sensed that the water inside has become far too hot and has shut down as a safety precaution.
Your boiler has stopped working because the water pressure is critically low and needs to be topped up.
Your boiler has stopped working because the internal fan, which clears exhaust fumes, is unable to start up correctly.
Your boiler has tried to light several times but has failed to produce a flame, meaning your heating and hot water will not work.
Your boiler has stopped working because the fan that removes waste gases is not spinning at the correct speed.
Your boiler has detected that water is heating up too quickly or flowing in the wrong direction, often because something is blocking the circulation of water through the system.
BoilerFaultCodes