11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has stopped working because it cannot circulate water properly, often due to a pump blockage or air trapped in the system.
Your boiler has detected a blockage or an airflow issue in the pipe that removes exhaust gases, which is preventing it from running safely.
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 talk to the remote control unit mounted somewhere else in your home.
Your boiler's internal computer is struggling to recognise its own settings due to an incorrect configuration of the small connection pins on its control board.
Your boiler is struggling to read its own internal water temperature, so it has shut down to prevent overheating.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage.
Your boiler's internal computer is experiencing a communication error, which has caused it to stop working for your safety.
Your boiler's waste water pipe is clogged, which is preventing it from safely draining away the excess moisture created during the heating process.
Your boiler has detected an issue with the sensor responsible for monitoring the safe removal of condensed water, which has caused it to stop working to prevent internal damage.
BoilerFaultCodes