12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has registered an issue with its internal programming or configuration settings, which requires a professional to safely reprogram or reset the system.
Your boiler has safely shut down because a sensor measuring the temperature of the exhaust gases leaving the flue is reading incorrectly or has failed.
Your boiler has detected a blockage or restriction in the internal pipe that drains away wastewater, which causes the system to shut down safely to prevent water from backing up.
Your boiler has temporarily stopped because it cannot detect enough water flowing through its main internal pipes.
Your boiler has detected an issue with the internal water pump, which means it cannot circulate water properly to provide your heating and hot water.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water inside its main heating system.
Your boiler has temporarily stopped working because it cannot safely confirm that air and exhaust gases are flowing properly.
Your boiler is failing to detect the flame when it tries to start up, so it is locking out for safety to prevent gas from building up.
Your boiler has temporarily shut down because it has detected dangerously high temperatures inside the unit.
Your boiler has detected an issue with the valve that controls the gas supply to the burner, meaning it has temporarily stopped working to keep your home safe.
Your boiler is having trouble managing the flow of water internally, which usually happens when an automatic valve inside gets stuck.
Your boiler is struggling to accurately measure the temperature of the water inside the heating system, which usually stops the central heating from working properly.
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BoilerFaultCodes