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 digital identity card, which means the main computer doesn't know how to operate the system safely.
Your boiler has developed a communication problem with its internal memory chip, meaning it cannot process the instructions needed to run properly.
Your boiler has switched itself off because the water pressure inside the system has dropped too low to operate safely.
Your boiler has lit correctly but the flame has gone out unexpectedly, meaning the system has shut down as a safety precaution.
Your boiler is failing to stay lit or cannot detect its own flame, meaning it has shut down for safety and will not provide heating or hot water.
Your boiler has detected an issue with the electrical fan, which is preventing it from safely clearing waste gases so it has shut down for safety.
Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit.
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 is having trouble readng the temperature outside, which means it cannot adjust its heating settings automatically to match the weather.
Your boiler has stopped working because it isn't receiving enough electrical power from the mains supply to run safely.
Your boiler's internal computer brain hasn't been programmed correctly and doesn't know how to run the system.
Your boiler's internal computer is having trouble communicating or hasn't been set up correctly, meaning the unit cannot safely manage its heating functions.
Your boiler has detected that the water is flowing in the wrong direction through the pipes or the temperature sensors have been installed backwards.
Your boiler is not detecting water moving through the system, which is preventing it from heating up safely.
Your boiler has detected that the temperature sensors are reading values in the wrong order, suggesting water may be moving the wrong way or a sensor has become loose.
Your boiler has detected that heat is moving through the pipes in the wrong direction or the sensors that measure temperature are giving confusing readings.
Your boiler has detected that the water is getting too hot too quickly, usually because it cannot circulate through your pipes and radiators properly.
Your boiler has tried to light several times but failed, so it has shut down for safety purposes to prevent unburnt gas from building up.
Your boiler has shut down because it has become too hot or there is not enough water moving through the system to keep it cool.
Your boiler has tried to light several times but cannot start safely, so it has locked itself out to prevent damage.
Your boiler has sensed a temperature sensor issue or a flow problem, causing it to shut down for safety to prevent overheating.
Your boiler has been manually reset too many times in a short period and has temporarily locked itself out to prevent damage.
Your boiler has detected an issue with the sensor that monitors the temperature of the water coming back into the unit, causing it to stop working for safety.
Your boiler thinks it sees a flame even though it isn't supposed to be running, causing it to shut down for safety.
Your boiler has likely experienced a temporary communication error and simply needs to be restarted.
Your boiler has detected that the incoming electrical supply is too weak or unstable to run the internal components safely.
Your boiler has lost the water pressure it needs to push heat around your home, causing it to shut down for safety.
Your boiler has switched itself off because it has reached too high a temperature, usually due to a lack of water or a blockage in the system.
Your boiler has stopped working because the internal pump that moves water around your pipes is stuck or seized.
Your boiler has overheated because a safety switch has tripped to protect the internal components, and it now needs to be manually restarted.
Your boiler has locked itself out because the reset button was pressed too many times in a short period while trying to clear another fault.
Your boiler is repeatedly trying and failing to ignite, causing it to lock itself out for safety.
Your boiler has lost water pressure and needs to be topped up to work properly.
BoilerFaultCodes