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 overheating and has automatically switched itself off to prevent damage.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected that the water pressure in your heating system is too high for it to operate safely.
Your boiler has lost the ability to monitor the temperature of your hot water supply, meaning it will likely stop producing hot water until the faulty sensor is replaced.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water used for your heating system.
Your boiler has detected a serious internal fault and has automatically shut itself down for safety reasons, meaning you currently have no heating or hot water.
Your boiler has detected that the water pressure inside the system is too low, preventing it from heating your home or water properly.
Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is struggling to push water around the system, which is preventing it from providing heating or hot water.
Your boiler has detected an issue with a secondary temperature sensor, which is preventing it from operating correctly.
Your boiler has detected that the flue gases are getting too hot, so it has safely shut itself down to prevent potential overheating or dangerous exhaust issues.
Your boiler has detected a potential issue with the ventilation system that clears away exhaust gases, so it has safely shut itself down to prevent any risk.
Your boiler is unable to safely move air through its system to burn gas properly, so it has shut down to prevent any 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 of the water heading to your radiators, meaning it cannot accurately manage your heating.
Your boiler has detected that a secondary heating circuit, such as underfloor heating, has become too hot and has automatically shut down for safety.
Your boiler is having trouble communicating with the secondary heating zone, which means a specific part of your home may not be receiving heat as requested.
Your boiler has lost the connection to the temperature sensor responsible for reading your solar water heating panel, which may cause your solar system to stop working temporarily.
Your boiler is having trouble communicating with the temperature sensor linked to your solar water heating system, which may prevent the solar panel integration from working correctly.
Your boiler is having trouble reading the temperature from your solar water heating system, which means it may not be able to use solar energy to warm your water right now.
Your boiler's electronic control system is misconfigured to expect a solar water heating setup that is not actually connected or properly recognised.
Your boiler has detected an issue with how its internal settings or electronic controls are communicating, which is preventing it from operating correctly.
Your boiler's internal computer system is struggling to communicate with its electrical components, meaning it cannot reliably operate your heating or hot water.
BoilerFaultCodes