25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 is struggling to accurately measure the temperature of your hot water, which means it has stopped providing it to prevent system errors.
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'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 has detected that one of the buttons on the control panel is stuck or faulty, preventing you from changing settings.
Your boiler has detected a problem with the sensor that monitors exhaust gases, and it has shut down for safety purposes.
Your boiler has lost its connection with the thermostat or control panel, meaning it cannot receive instructions to turn on or off.
Your boiler has stopped working because the electricity supply coming into the unit has dropped below the minimum level required to operate safely.
Your boiler has started an ignition process but lost its flame unexpectedly, causing the system to shut down for safety.
Your boiler has lost the signal that confirms a flame is burning, so it has shut down for safety.
Your boiler is struggling to circulate water properly because there is a significant temperature difference between the water leaving and returning to the unit.
Your boiler is still working but cannot reach its full power, meaning your radiators might not get as hot as they should.
Your boiler has detected that the water returning from your radiators is too hot, causing it to shut down for safety to prevent damage to the system.
Your boiler has lost its wireless connection with your thermostat or remote control, meaning they can no longer talk to each other to manage your heating.
Your boiler is unable to move water around your heating system effectively because the pump is not operating correctly.
Your boiler's water pump is struggling because it has trapped air inside, preventing it from circulating heat effectively around your home.
Your boiler is confused because it detects that the water returning to the system is hotter than the water leaving it, which shouldn't happen during normal operation.
Your boiler is struggling to accurately measure the temperature of the water circulating inside it, so it has stopped working to prevent potential damage.
Your boiler is unable to read the temperature of the water circulating inside it, so it has safely shut down to prevent overheating.
Your boiler is simply reminding you that it is due for its annual safety service to keep it running efficiently and safely.
Monthly cover means no unexpected bills when your boiler breaks down.
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BoilerFaultCodes