20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that its two internal temperature sensors are giving very different readings, suggesting a potential circulation issue or a faulty component.
Your boiler has detected a technical issue with the sensor that monitors water temperature returning to the unit, causing it to stop working for safety.
Your boiler has stopped working because it cannot detect a flame, which is likely due to an internal electronic fault or a problem with the gas supply valve.
Your boiler has shut down because it detected a dangerous temperature difference between the water leaving the boiler and the water returning to it, suggesting it is overheating.
Your boiler has detected a temperature mismatch and has locked itself to prevent overheating, requiring a system recalibration to restart.
Your boiler has detected an issue with a secondary temperature sensor used to monitor the hot water leaving the unit, which may cause it to stop working for safety.
Your boiler has detected an electrical issue with the gas control valve, meaning it cannot safely regulate the fuel needed to stay alight.
Your boiler has detected an internal electrical fault with the gas control system and has shut down as a safety precaution.
Your boiler has detected an electrical fault with the gas control valve, preventing it from safely lighting the burner to provide heating or hot water.
Your boiler has detected a communication problem with its internal gas valve or the wiring connected to it, preventing the system from operating safely.
Your boiler has shut down because it has repeatedly struggled to ignite or maintain a stable flame correctly.
Your boiler is not receiving enough gas to operate safely or efficiently, which is causing it to shut down.
Your boiler's main control board has detected an internal electronic failure and has shut down to protect its components.
Your boiler is struggling to maintain a steady flame because it cannot properly monitor the combustion process.
Your boiler is struggling to ignite or maintain a stable flame because the internal combustion levels are not reaching the required safety threshold.
Your boiler is struggling to get the right mix of air and gas for the flame, causing it to shut down for safety.
Your boiler is struggling to burn gas correctly and cannot reach its required power levels, so it has shut down as a precaution.
Your boiler is struggling to keep its flame burning consistently, causing it to cut out for safety.
Your boiler has encountered a digital 'glitch' or software error while trying to start up, preventing it from running safely.
Your boiler's main internal computer has developed a serious fault and is no longer able to control the system.
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BoilerFaultCodes