12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has temporarily shut down because the internal water temperature has become too hot.
Your boiler has detected an internal sensor or safety check failure and has safely locked itself out to prevent unsafe operation.
Your boiler has failed to light after five attempts and has safely locked itself out to prevent a gas build-up.
Your boiler has sensed that the exhaust gases are becoming too hot, causing it to shut down automatically for your safety.
Your boiler has shut down because a temperature sensor is faulty or the main unit has become too hot to operate safely.
Your boiler is detecting that a small amount of gas may still be burning briefly after it is supposed to have turned off.
Your boiler has stopped working because its internal fan isn't spinning at the correct speed or the system cannot detect that it is running.
Your boiler has detected an internal electronic or safety system failure and failed to ignite, meaning it has shut down to keep your home safe.
Your boiler has lost its connection to its internal memory chip or cannot detect a flame, meaning it cannot operate safely.
Your boiler appears to have no power at all, meaning the control panel is blank and the unit will not start.
Your boiler is briefly starting up before shutting down because it cannot detect water flowing properly through the system.
Your boiler is struggling to operate because the electrical supply is unstable or too low, preventing the flame from starting safely.
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BoilerFaultCodes