19 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 internal electronics that simulate the flame, meaning it cannot safely start or maintain a burn.
Your boiler has stopped working because a sensor that monitors water temperature has failed, preventing the system from firing up.
Your boiler has stopped working because its internal safety sensors can no longer monitor the temperature of the exhaust gases.
Your boiler has stopped working because a temperature sensor on the pipework is broken or sends an incorrect signal, preventing the burner from lighting.
Your boiler is not lighting because it is unable to draw the gas it needs to create a flame.
Your boiler has stopped working because the internal computer cannot communicate with the fan that clears exhaust gases.
Your boiler has failed to ignite because the internal control board is not receiving or sending the electricity required to create a flame.
Your boiler's computer control board has encountered a software data error or is mismatched with the boiler, causing it to stop providing heating and hot water.
Your boiler's electronic control board is unable to recognize a small coding chip that tells it how to operate correctly.
Your boiler's electronic command chip is failing to communicate with the main control board, preventing the system from firing up safely.
Your boiler's main control board has lost connection with its configuration chip or the chip is incorrect, meaning the system cannot safely confirm if the burner is lit.
Your boiler's electronic control board has a communication error with its security chip or is failing to recognize the ignition signal.
Your boiler's main control board has lost connection with its security chip or has been configured incorrectly following a repair.
Your boiler is struggling to circulate water properly, causing the flame to cut out shortly after it starts to prevent overheating.
Your boiler has detected that there is not enough water flowing through the system or there is a lack of pressure to operate safely.
Your boiler's internal computer chip has lost communication or failed to recognise the burner, causing the system to shut down for safety.
Your boiler has no power and the screen is completely blank, meaning it cannot provide any heating or hot water until electrical flow is restored.
Your boiler is failing to detect when you turn on the hot tap, meaning it isn't heating the water for your shower or taps.
Your boiler has lost all power and is completely unresponsive, meaning it cannot provide heating or hot water until the electrical fault is resolved.
BoilerFaultCodes