26 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 or detected an internal control error, so it has safely shut down to prevent gas from escaping.
Your boiler has detected a flame inside when there shouldn't be one and has shut itself down as a safety precaution.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal parts.
Your boiler has failed to ignite because it cannot detect a flame, meaning your heating and hot water will not work.
Your boiler is failing to detect a flame, which means it cannot safely light to provide you with heating or hot water.
Your boiler has failed to detect a flame, meaning it cannot ignite safely to provide heating or hot water.
Your boiler is failing to detect a flame, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has detected an issue with the internal fan that pushes exhaust gases out of the flue, so it has purposefully turned itself off to stay safe.
Your boiler has detected that the water pressure inside the system is likely too low to operate safely and effectively.
Your boiler has detected that the water pressure inside the heating system is too low to operate safely.
Your boiler is struggling to detect the flow or pressure of water moving through the system, which is preventing it from heating your home or water reliably.
Your boiler has detected an issue with the electricity supply entering the unit, which is preventing it from operating safely.
Your boiler's computer system has lost its internal settings, preventing it from knowing how to operate your specific heating system correctly.
Your boiler's electronic control system is failing to correctly regulate the gas flame, causing it to shut down to prevent unsafe operation.
Your boiler is failing to detect the flame correctly, so it has safely shut itself down to prevent a gas buildup.
Your boiler has detected that the water is not circulating correctly or that there is a significant temperature difference between the pipes, causing it to shut down for safety.
Your boiler is struggling to accurately read or detect the temperature of the water circulating through your heating system.
Your boiler has detected that the water temperature readings between the flow and return pipes are inconsistent, causing it to shut down to prevent damage.
Your boiler has detected that it is not burning gas correctly, which poses a serious risk of carbon monoxide fumes being released into your home.
Your boiler has detected that fumes are not escaping through the flue as they should, which means the system has shut down to keep your home safe.
Your boiler is failing to detect a flame, meaning it cannot ignite or stay lit to provide you with heating or hot water.
Your boiler has detected that the temperature of the exhaust gases leaving the unit is higher than it should be, so it has shut down as a safety precaution.
Your boiler has detected that the internal heating surfaces are becoming obstructed, which prevents it from transferring heat effectively and could cause it to stop working soon.
Your boiler has detected that the fuel-burning process is not working efficiently, which poses a serious risk of carbon monoxide poisoning.
Your boiler has detected that it is not burning gas correctly, which poses a serious carbon monoxide safety risk, so it has shut itself down to keep you safe.
Your boiler is failing to detect the flame correctly, so it has shut itself down to prevent an unsafe build-up of gas.
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BoilerFaultCodes