26 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's temperature sensor is failing to provide an accurate reading, which stops the system from knowing how much to heat your water.
Your boiler's internal sensor responsible for reading water temperatures has lost its connection, preventing the system from heating your home safely.
Your boiler has detected a faulty connection in a temperature sensor that monitors internal heat levels, causing the system to stop working as a safety precaution.
Your boiler's secondary system is misreading the temperature because a connection to a heat sensor has become loose or damaged.
Your boiler has lost the connection to the temperature sensor responsible for your hot water, meaning it cannot accurately heat your taps.
Your boiler's control system is struggling to read a temperature sensor, which has likely caused it to stop working to avoid potential damage.
Your boiler is struggling to read a temperature signal from an internal sensor, which is likely caused by a loose wire or a faulty connection.
Your boiler's control system has lost the connection to one of its temperature monitoring sensors, preventing it from operating correctly.
Your boiler's internal computer is currently misconfigured, which is preventing it from starting up correctly.
Your boiler has stopped circulating water, meaning it cannot heat your home or provide hot water because the internal pump is not working.
Your boiler has detected that the water being sent to one of your heating circuits is getting hotter than it should be, so it has safely paused the heating to prevent damage.
Your boiler has detected that the water inside the system is dangerously cold and is taking precautions to prevent the pipes from freezing.
Your boiler's internal control panel has lost communication with the main system, meaning the boiler has stopped working because it no longer knows how or when to heat your home.
Your boiler's electronic control system is failing to communicate correctly with its internal temperature sensors, causing it to stop operating as a safety precaution.
Your boiler has detected that there is not enough water flowing through the system to operate safely, so it has shut down to protect itself.
Your boiler has stopped running as a safety precaution because it couldn't successfully light or maintain a flame.
Your boiler's internal temperature sensor is reporting an error, which means the system cannot monitor its own heat levels and has shut down as a precaution.
Your boiler's burner has shut itself down for safety and requires a manual restart to try and restore heating and hot water.
Your boiler has reached an unsafe temperature and has automatically shut down to prevent damage.
Your boiler has detected that it has become dangerously hot and has automatically shut itself down to prevent damage, requiring a manual reset.
Your boiler has stopped running because it has locked itself out, usually because it can't draw enough oil or light the flame.
Your boiler has automatically shut down because it has detected that the water inside has become dangerously hot.
Your boiler has stopped working because the burner failed to ignite after multiple attempts, so it has shut down for safety reasons.
Your boiler has detected a problem and safely shut itself down to prevent any further issues, meaning you currently have no heating or hot water.
Your boiler has switched itself off because it got too hot, acting as a safety measure to prevent damage.
Your boiler has detected that it is getting too hot and has automatically switched itself off to stay safe.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes