9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has successfully lit its pilot light and is now ready to heat your home.
Your boiler has completely lost power, meaning it cannot start the heating or hot water process.
Your boiler has detected a problem and has shut itself down for safety, meaning your heating and hot water will stop working until it is reset or repaired.
Your boiler is receiving a constant electrical signal even when it should be off, often caused by a faulty external control or internal component failure.
Your boiler's electronic control box has detected an internal electrical failure or a timing error that prevents it from starting the ignition process.
Your back boiler is receiving constant electricity but is not responding, which usually indicates the internal controller or a safety sensor has failed.
Your boiler is attempting to light but is failing to recognize the flame or ignite successfully.
Your back boiler is receiving two different electrical power signals at the same time, which is causing a control conflict and preventing it from running properly.
Your boiler is trying to light the flame but can't quite get the fire started, despite the igniter clicking.
BoilerFaultCodes