23 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler has detected that the water pressure in your heating system is currently set too high for safe operation.
Your boiler has detected a fault with the sensor responsible for measuring the temperature of your hot water, so it has shut down to prevent incorrect operation.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water being sent to your radiators.
Your boiler has detected a safety-related issue and has automatically shut itself down to prevent damage or dangerous operation.
Your boiler has detected that the water pressure inside the system is too low to operate safely.
Your boiler has failed to ignite or stay lit because it cannot detect a flame, so it has safely shut down to prevent gas from escaping.
Your boiler is struggling to push water around your heating system, which is often caused by trapped air, a blockage, or a pump that has stopped working.
Your boiler has detected an issue with a secondary sensor that monitors the temperature of the water or heating circuit, causing it to stop operating to stay safe.
Your boiler has detected an issue with the sensors that monitor the safety and flow of exhaust gases, so it has shut itself down to prevent any risk.
Your boiler has detected an issue with the sensor that monitors the air and fumes inside the unit, meaning it has safely shut itself down to prevent any risk.
Your boiler has detected an issue with the internal ventilation system that removes exhaust gases, and as a safety precaution, it has stopped running to prevent unsafe operation.
Your boiler has detected that the water temperature in one of your heating circuits has become dangerously high and has automatically shut down to prevent damage.
Your boiler has lost the signal from a sensor responsible for monitoring the temperature in your underfloor or radiator heating zones, which may stop those specific rooms from heating up correctly.
Your boiler has detected that the water temperature in your secondary heating circuit has become too hot, causing it to shut down for safety.
Your boiler is having trouble communicating with the secondary heating circuit that controls a specific part of your home, such as an underfloor heating zone.
Your boiler's solar water heating system is unable to read the temperature from the roof panel, meaning the solar energy collection feature is currently disabled.
Your boiler is having trouble communicating with the temperature sensor linked to your solar water heating system, which may prevent the boiler from correctly using solar energy to heat your water.
Your boiler is having trouble communicating with the temperature sensor connected to your solar water heating system, which may prevent the solar panels from working correctly.
Your boiler's electronic control system is incorrectly set up to communicate with solar thermal panels that are not currently part of your heating arrangement.
Your boiler is displaying a communication error because it is struggling to recognise an internal setting or a connected external control accessory.
Your boiler's internal electronic system is failing to communicate correctly between its control modules, meaning the unit cannot safely start.
BoilerFaultCodes