33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has tried to start several times but was unable to light the internal flame.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has detected that waste gases are not being cleared away safely and has automatically shut down to prevent a build-up of fumes.
Your boiler is trying to start, but it cannot successfully ignite or keep the flame burning to heat your water.
Your boiler's control system has lost its internal connection to the parts responsible for lighting the flame, meaning it cannot start up to provide heat or hot water.
Your boiler has stopped working because it cannot move air through the system properly, which prevents it from igniting safely.
Your boiler has detected an issue with the ventilation system that clears exhaust gases, so it has safely shut itself down to prevent any unsafe fumes from building up.
Your boiler's computer system has encountered a critical internal error and is unable to operate safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected that the internal components responsible for expelling exhaust gases are not working correctly, causing it to shut down for safety reasons.
Your boiler has detected that the exhaust gases leaving the system are dangerously hot, so it has safely shut itself down to prevent damage.
Your boiler has detected that the water inside the unit is getting too hot and has automatically shut down to prevent damage.
Your boiler has detected that the water returning from your radiators is too hot, which suggests a possible circulation issue within your heating system.
Your boiler has stopped producing heat and hot water because it is failing to accurately measure the internal temperature of the water.
Your boiler is struggling to accurately measure the temperature of the water returning to it, which causes it to stop operating correctly to protect itself.
Your boiler is struggling to accurately detect the temperature of your hot water supply, so it has stopped heating it to prevent the system from overheating.
Your boiler has detected an issue with the sensor that monitors the safety of the exhaust gases, and it has stopped working as a safety precaution.
Your boiler is struggling because it has lost the signal from an optional outdoor temperature sensor, so it is reverting to a simplified operating mode.
Your boiler's internal computer is experiencing a critical error and cannot communicate with the rest of the heating system, preventing it from functioning.
Your boiler's internal computer is experiencing a critical error and needs to be attended to by a professional engineer to restore your heating and hot water.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has detected an issue with its exhaust system multiple times today and has safely shut down to prevent harmful fumes from entering your home.
Your boiler's fan, which is essential for safely venting exhaust gases, is failing to respond correctly, causing the system to stop working to ensure your safety.
Your boiler is temporarily shutting down because the electricity supply from your home is too weak to operate it safely.
Your boiler has detected that the electricity supply coming into your home is not steady, causing it to shut down for safety.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to read the outside temperature because the external sensor is disconnected or faulty.
Your boiler has lost water pressure repeatedly over the last day, which has caused it to stop working to avoid internal damage.
Your boiler's internal computer is confused because its internal temperature sensors are either disconnected or are reading temperatures that suggest they have been installed in the wrong positions.
Your boiler has detected that the temperature readings from its internal sensors don't match, causing it to shut down for safety.
Your boiler has detected that the water inside the system is getting too hot, too quickly, and has shut itself down to prevent any damage.
Your boiler is struggling to detect the water pressure inside the system, which is preventing it from safely starting up.
Your boiler is currently unable to control the flow of gas correctly, so it has shut itself down to ensure your safety.
BoilerFaultCodes