33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost its configuration settings and cannot function because it doesn't recognize its internal identity chip.
Your boiler's internal computer memory chip has either failed or is not being recognised, preventing the system from operating.
Your boiler has stopped working because there is not enough water inside the system to operate safely.
Your boiler has started an ignition process but the flame has gone out, meaning your system has shut down for safety.
Your boiler has lost its flame suddenly and has shut down as a safety precaution, meaning you will have no heating or hot water until it is fixed.
Your boiler has stopped working because the internal fan, which safely pushes exhaust gases out of the flue, is not running correctly.
Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit, causing it to stop heating for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water coming back into the unit, preventing it from heating correctly.
Your boiler has lost connection with its outdoor thermometer, which helps it adjust the heating temperature based on the weather outside.
Your boiler has detected that the electrical supply coming into your home is or has been below the required level to operate safely.
Your boiler's internal computer has not been set up correctly to tell it which model it is, meaning it doesn't know how to operate safely.
Your boiler's internal computer brain is confused or has lost its settings, meaning the unit cannot safely start or run.
Your boiler has detected that the hot water pipes leaving and returning to the unit have been installed or connected the wrong way round.
Your boiler is unable to move water around the system, which is preventing it from heating your home or water.
Your boiler has detected that heat is moving through the pipes in the wrong direction or a temperature sensor has come loose.
Your boiler has detected that its temperature sensors are picking up heat in the wrong order, suggesting a sensor has come loose or failed.
Your boiler has detected that the water is getting too hot too quickly, usually because the water isn't flowing through the system properly.
Your boiler has failed to light several times and has shut down for safety, meaning you currently have no heating or hot water.
Your boiler has stopped working because the water inside has become too hot or is not circulating through the system correctly.
Your boiler has stopped working because it failed to light several times, often due to a lack of gas supply or a blocked pipe.
Your boiler has detected that it is heating up too quickly or isn't circulating water properly, causing it to shut down to prevent damage.
Your boiler has been manually reset too many times in a short period and has temporarily locked itself out as a safety precaution.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators, preventing it from heating correctly.
Your boiler thinks it sees a flame even though it hasn't actually started the ignition process, causing it to shut down for safety.
Your boiler has encountered a temporary electronic error and simply needs to be rebooted to clear the message.
Your boiler is not receiving enough electrical power to operate safely, which is often caused by a general power supply issue or a faulty internal pump.
Your boiler has detected that there is not enough water in the system to operate safely, causing it to shut down to prevent damage.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has stopped working because the internal pump that moves water around your pipes is stuck or seized up.
Your boiler has overheated and shut itself down as a safety precaution to prevent damage to the internal components.
Your boiler has locked itself out because the reset button was pressed too many times in a short period to prevent damage.
Your boiler is repeatedly trying and failing to ignite, causing it to lock itself out for safety after five unsuccessful attempts in a short period.
Your boiler has lost water pressure, meaning there isn't enough water in the system to operate safely and effectively.
BoilerFaultCodes