21 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to light the flame needed to heat your water and home, so it has safely shut itself down.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage or safety issues.
Your boiler is struggling to clear exhaust gases safely, so it has shut down to prevent any risk of fumes entering your home.
Your boiler has lost the ability to accurately measure the water temperature, so it has shut down to prevent overheating.
Your boiler is struggling to detect the temperature of your hot water, so it has stopped heating it to prevent the system from overheating.
Your boiler has stopped working because it cannot detect the flame needed to produce heat.
Your boiler is trying to start but cannot light the internal flame, which means it has safely shut down to prevent gas from building up.
Your boiler is failing to light the flame needed to produce heat or hot water.
Your boiler has stopped because the internal flame went out unexpectedly while it was trying to heat your water or home.
Your boiler is failing to shut off its flame properly because of a potential issue with the internal gas controls; you should turn off the gas supply at the meter immediately for your safety.
Your boiler is struggling to clear exhaust gases due to a blockage in the air vent pipes or a faulty safety sensor.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has lost the ability to measure the temperature of the water being sent to your radiators, so it has shut down to prevent overheating.
Your boiler is currently unable to correctly measure the temperature of the water it is heating, so it has stopped providing hot water to keep the system safe.
Your boiler has detected a communication error with its internal safety thermostat and has shut down to prevent the system from overheating.
Your boiler has stopped working because it does not have enough water inside the system to operate safely.
Your boiler has detected that the water pressure inside the heating system is too high and has shut itself down to prevent damage.
Your boiler has detected a problem with the part that controls the gas supply to the burner, meaning it cannot safely start or maintain a flame for heating or hot water.
Your boiler is struggling to push water around your heating system because the internal pump is stuck, meaning you currently have no heating or hot water.
Your boiler has detected that the water inside it is dangerously hot and has shut itself down to prevent any damage.
Your boiler has stopped working because the amount of water in your central heating system is either too low or too high.
BoilerFaultCodes