22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost the internal connection between its control units, causing it to stop operating completely for safety reasons.
Your boiler has lost its connection to your room thermostat or central heating controller, meaning it doesn't know when to turn the heating on.
Your boiler's electronic control system has lost the connection to its main internal heat controller, causing it to stop functioning correctly.
Your boiler has stopped working because it cannot safely ignite or clear away waste gases, which may be caused by a blockage in the flue or drain pipes.
Your boiler has detected that it cannot safely get rid of exhaust gases or is struggling to take in fresh air, so it has shut down to keep you safe.
Your boiler has detected a flame inside when it shouldn't be there, which has caused it to shut down for safety.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that the internal part responsible for pushing out exhaust gases is not spinning correctly, so it has safely shut itself down to prevent any unsafe operation.
Your boiler has detected that the water pressure is too low or inconsistent to safely provide heating and hot water.
Your boiler is struggling to detect the flow of water because its internal sensor is faulty, which is preventing it from heating your water properly.
Your boiler has lost the ability to accurately measure the temperature of the hot water it produces, so it has stopped heating your taps to prevent potential overheating.
Your boiler is having trouble measuring the temperature of the water used for your taps and shower, so it has stopped heating that water to prevent it from getting too hot.
Your boiler is struggling to detect the flow of water through the system, which means it has stopped producing hot water and heating to prevent damage.
Your boiler has detected that the water inside the system is becoming dangerously hot, so it has safely shut itself down to prevent damage.
Your boiler has detected that the water temperature difference between the pipes entering and leaving the unit is not what it should be, causing it to shut down to prevent damage.
Your boiler has lost the ability to accurately measure the temperature of the water being sent to your radiators, causing it to stop running to prevent damage.
Your boiler has lost the ability to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler has detected that the water returning to it from your radiators is getting too hot, so it has safely shut itself down to prevent damage.
Your boiler has detected that the water is not circulating between the heating pipes as expected, causing the system to shut down to prevent overheating.
Your boiler's computer software is not communicating correctly with the internal parts, causing the system to lock out for safety.
Your boiler's internal timer is malfunctioning, which means it cannot accurately track when your heating or hot water should turn on or off.
Your boiler is having a communication breakdown with its external thermostat or smart control system, meaning it doesn't know when to turn on or off.
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BoilerFaultCodes