22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with the gas pressure or a component failure and has shut down as a safety precaution.
Your boiler has shut down because the electrical power coming into it is too weak or unstable to run safely.
Your boiler has detected an internal communication error and has shut itself down as a safety precaution.
Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
Your boiler has stopped working because the burner isn't lighting correctly, likely due to a problem with the internal airflow or the ignition system.
Your boiler has shut itself down as a safety precaution because it has detected an overheating issue within the system.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
Your boiler is getting too hot too quickly and is shutting itself down to prevent damage.
Your boiler's computer has become stuck in a repeating internal test sequence and is failing to move into its normal heating mode.
Your boiler has failed to ignite or stay lit, meaning your heating and hot water have stopped working.
Your boiler has sensed that the internal pump is malfunctioning or water is not circulating correctly, which has caused the system to stop as a safety precaution.
Your boiler has detected that the water pump is likely stuck or not moving water correctly, which means the system cannot heat up safely.
Your boiler is having trouble 'talking' to your thermostat, which means it might not know when to turn your heating on or off.
Your boiler has identified a problem with the ventilation system and has shut down as a safety precaution because it cannot confirm that exhaust fumes are being cleared correctly.
Your boiler has shut down because it cannot correctly control the flow of gas needed to stay alight.
Your boiler has detected trapped air inside it which is preventing it from starting up safely.
BoilerFaultCodes