29 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light the internal flame, which means it cannot provide heat or hot water.
Your boiler has automatically shut itself down because it has become dangerously hot.
Your boiler has temporarily stopped working because the exhaust pipe is getting too hot.
Your boiler has lost electrical communication with its internal gas valve, which stops it from safely supplying gas to heat your home.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water flowing through your heating system.
Your boiler has detected an internal fault with the domestic hot water temperature setting.
Your boiler has locked itself out because it has been manually reset too many times in a short period.
Your boiler has temporarily stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has lost connection to the temperature sensor in your hot water cylinder, meaning it may not know how hot your stored water is.
Your boiler's computer system is confused because it has not been set up correctly for your specific heating system.
Your boiler has stopped working because the internal fan, which safely helps the system breathe and clear exhaust gases, is not spinning correctly.
Your boiler is struggling to detect the flame needed to heat your water, even if the burner has successfully lit.
Your boiler is temporarily shutting down because it is getting incorrect temperature readings from the water returning inside the system.
Your boiler's control panel detects that one of the buttons is jammed or being held down permanently, which is stopping the system from operating normally.
Your boiler's main control system has experienced a software glitch and needs to be reset or professionally evaluated.
Your boiler has detected a faulty reading from the temperature sensor measuring your exhaust gases, so it has safely shut down to prevent potential overheating.
Your boiler has lost its digital connection to your room thermostat, meaning it no longer knows when to turn the heating on or off.
Your boiler is failing to start because it isn't receiving enough electricity from your home's power supply.
Your boiler is struggling to keep the flame lit and is automatically trying to restart itself to get your heating or hot water working again.
Your boiler is struggling to keep its internal flame lit while it is running, so it has safely shut down to prevent any issues.
Your boiler is struggling to move water through the system efficiently, causing it to overheat very quickly.
Your boiler is getting too hot inside its exhaust path, so it has automatically turned down its power to prevent any internal damage.
Your boiler is struggling to talk to your wireless thermostat, meaning it doesn't know when to turn your heating on or off.
Your boiler's water circulation pump has stopped working, which means the system cannot move hot water to your radiators or taps.
Your boiler is struggling because there is trapped air inside the system, which is preventing hot water from circulating properly to your radiators.
Your boiler is struggling to accurately measure the temperature of the water inside it, so it has shut down to prevent overheating.
Your boiler is having trouble measuring water temperatures, so it has stopped working to prevent any damage to the internal system.
Your boiler is completely shut down with only a single dot visible on the display, meaning it has lost power or the main control board has turned off.
Your boiler is simply displaying a routine reminder that it has been a year since its last service.
Monthly cover means no unexpected bills when your boiler breaks down.
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BoilerFaultCodes