15 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is struggling to control its internal gas supply, which means it has safely shut itself down to prevent any risk of incomplete combustion.
Your boiler is struggling to control the gas supply it needs to stay lit, so it has shut down to keep your home safe.
Your boiler is struggling to manage the gas supply required to light the flame and heat your water, which has caused it to shut down for safety.
Your boiler has lost communication with an optional safety monitoring device, which is preventing it from operating correctly.
Your boiler has lost communication with an optional safety device, meaning it has shut down as a precaution to prevent unsafe operation.
Your boiler is having a communication error with an optional safety monitoring device, which is causing the system to stop functioning as a precaution.
Your boiler has detected that the water inside the heating system has become too hot and has automatically shut down to prevent damage.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler is struggling to circulate water properly or is overheating because it cannot detect the expected changes in water temperature.
Your boiler has stopped because it cannot maintain a stable flame to heat your water.
Your boiler is failing to light because it cannot detect a flame, which may be caused by a temporary gas supply issue.
Your boiler is trying to start but cannot detect a flame, likely because the gas supply is blocked or the ignition system is failing to spark.
Your boiler is failing to light because it is not receiving enough gas or is having trouble sparking, meaning you currently have no heating or hot water.
Your boiler has detected an issue with the system that controls the flow of gas, meaning it has shut itself down to keep your home safe.
Your boiler is having trouble controlling the flow of gas needed to stay lit, so it has shut down as a safety precaution.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes