33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Combi
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Your boiler has failed to recognize its internal memory chip, meaning it has forgotten its specific settings and cannot operate for your safety.
Your boiler's electronic memory card has developed a communication fault or is missing, preventing the system from operating.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has started to fire up but the flame has gone out, meaning the system has shut down for safety.
Your boiler is failing to stay lit or cannot detect its own flame, meaning it has stopped providing heating and hot water for safety.
Your boiler has detected an issue with the electrical fan, meaning it cannot safely clear exhaust fumes and has stopped running for safety.
Your boiler has lost its ability to accurately measure the temperature of the water leaving the unit, meaning it cannot operate safely and has shut down as a precaution.
Your boiler has lost its ability to accurately measure the temperature of the water coming back from your radiators, which prevents it from running smoothly.
Your boiler's external temperature sensor has stopped communicating correctly, which means the system may struggle to adjust your heating efficiency based on the weather outside.
Your boiler has detected that the incoming electricity supply is not at the correct voltage, meaning it cannot operate safely or effectively.
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 has lost its settings or suffered an electrical failure, meaning it can no longer communicate with the rest of the unit.
Your boiler has detected that the water pipes connected to the unit are likely installed in the wrong positions, or a sensor is misreading the temperature direction.
Your boiler has stopped working because there is not enough water pressure or flow to safely circulate around the system.
Your boiler has detected that the temperature sensors on the main pipes are confused, likely because a internal sensor has come loose or failed.
Your boiler has sensed that the water temperatures are the wrong way around, likely because a sensor has come loose or stopped working correctly.
Your boiler has detected that the water is heating up too quickly or not circulating properly, which usually means the water flow is blocked.
Your boiler has tried to light several times but cannot establish a stable flame, meaning your heating and hot water will not work.
Your boiler has stopped working because it has detected it is getting too hot too quickly or there is not enough water moving through the system.
Your boiler has tried to light several times but cannot establish a flame, meaning it has shut down for safety.
Your boiler has detected that water is either not moving through the system or a temperature sensor has failed, causing it to shut down to prevent overheating.
Your boiler has been manually reset too many times in a short window and has now locked itself out for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, causing it to stop running for safety.
Your boiler thinks it sees a flame even though it hasn't started yet, which is causing it to shut down for safety.
Your boiler has likely experienced a temporary communication error or a small software glitch during startup.
Your boiler is not receiving enough electrical power to operate correctly, which is often caused by a general power issue or a faulty internal component.
Your boiler has detected that the water level inside the system is too low to operate safely, which is usually caused by a small leak or air being bled from radiators.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler's internal water circulator has stopped spinning, which prevents heat from moving through your home and can cause the system to shut down.
Your boiler has overheated and shut itself down as a safety precaution to prevent damage.
Your boiler has been manually reset too many times in a short window and has temporarily locked itself to prevent potential damage or mask an underlying fault.
Your boiler is trying to fire up too many times in a short window because it is struggling to stay lit, causing it to lock itself out for safety.
Your boiler has lost the water pressure it needs to push heat around your home, likely due to a small leak or air in the system.
BoilerFaultCodes