17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a critical internal error in its safety monitoring system and has automatically shut down to prevent unsafe operation.
Your boiler has failed to light the burner after trying to start and requires a professional inspection of the ignition system.
Your boiler has detected an internal safety error where it thinks a flame is present when it should be switched off, causing it to lock itself out to prevent a hazard.
Your boiler's internal computer is failing to communicate with a key electronic key, meaning the system cannot reliably start or maintain a flame.
Your boiler has detected an internal computer error and is unable to start or maintain its flame, so it has shut down for safety.
Your boiler is struggling to circulate water properly or is sensing that it is overheating instantly, causing it to shut down for safety.
Your boiler has stopped working because it is not receiving a stable power supply or is failing to light the burner safely.
Your boiler's computer is experiencing a memory error and cannot detect the burner flame, meaning it has shut down for safety.
Your boiler is failing to start because it cannot detect that the internal fan is spinning correctly to vent exhaust gases safely.
Your boiler is failing to shut off the gas supply properly after it has finished heating, which poses a significant safety risk.
Your boiler has stopped working because it is struggling to detect heat or confirm a flame is burning safely, so it has shut down to protect itself.
Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut down to prevent damage or safety issues.
Your boiler has failed to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is failing to ignite because it is not receiving enough gas to produce a flame.
Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage or safety issues.
Your boiler is failing to detect when you turn on the hot tap, so it isn't heating the water for your shower or kitchen faucet.
Your boiler has detected that it is running much hotter than it should be and has shut itself down as a safety precaution to prevent damage.
BoilerFaultCodes