34 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has tried to start up several times but failed to ignite the gas safely, so it has temporarily shut itself down.
Your boiler has detected a flame inside when it shouldn't be burning, so it has locked itself out for safety.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has successfully lit but the flame has gone out unexpectedly, meaning it cannot stay on to heat your home or water.
Your boiler has stopped working because it cannot detect that the internal fan, which safely pushes exhaust gases outside, is running properly.
Your boiler has temporarily stopped working because it cannot accurately measure the temperature of the water flowing through the system.
Your boiler is temporarily locked out because it is receiving an incorrect temperature reading from the pipe returning water back into the system.
Your boiler has lost connection to the weather sensor outside your home, meaning it can no longer automatically adjust your heating based on the outside temperature.
Your boiler has detected that the pipes carrying water in and out of the system have been installed the wrong way around.
Your boiler's hot water cylinder sensor is not working properly, which means it cannot accurately monitor the temperature of your stored hot water.
Your boiler has paused because an external safety device, such as a room thermostat, fire safety valve, or system interlock, has been triggered or disconnected.
Your boiler has lost communication with its internal control chip, meaning it cannot operate safely and has shut down.
Your boiler is still providing hot water for taps, but the radiators are not coming on for central heating.
Your boiler is still keeping your home warm, but it has stopped heating your water for taps and showers.
Your boiler has completely lost power to its control panel, meaning it is switched off and will not provide heating or hot water.
Your boiler has lost communication with its external control system, meaning it is not receiving the signals needed to regulate its temperature properly.
Your boiler has lost connection to its electronic control chip, which means it cannot operate safely and has shut down.
Your boiler's hot water sensor has stopped working correctly, which means it cannot properly monitor the temperature of your stored hot water cylinder.
Your boiler has temporarily locked out because it mistakenly detects a flame when it shouldn't be burning.
Your boiler has stopped working because an external safety device or room control connected to it has been triggered or disconnected.
Your boiler has sensed a flame inside when it shouldn't be burning, so it has safely shut itself down to prevent any risk.
Your boiler has stopped working because the internal fan that safely pushes out harmful gases is not operating correctly.
Your boiler has safely shut down because the internal burner flame has unexpectedly gone out while trying to heat your home.
Your boiler's temperature sensor is providing faulty information, causing it to stop operating to ensure your safety.
Your boiler has detected that the water inlet and outlet pipes were connected the wrong way around during installation.
Your boiler has stopped trying to light because it failed to detect a flame, meaning you currently have no heating or hot water.
Your boiler has tried to start up multiple times but failed to ignite the gas safely, so it has locked itself out to prevent any issues.
Your boiler has stopped because the electricity supply from your home's mains is too weak.
Your boiler has temporarily stopped working because the amount of water inside the system has dropped too low to run safely.
Your boiler is having trouble communicating with the temperature sensor located outside your home, so it is using a default setting to keep your heating running.
Your boiler has temporarily shut down because the internal water temperature became too high, acting as a crucial safety measure to prevent damage.
Your boiler's main electronic brain has encountered a critical error or lost its configuration chip, causing the system to shut down safely.
Your boiler is temporarily unable to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler has locked itself out for safety because it has been manually reset too many times in a short period.
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BoilerFaultCodes