14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar Oil Regular
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Your boiler is overheating because it cannot correctly measure or circulate the water inside it.
Your boiler is failing to ignite because it is not receiving the necessary signals or power to start the heating process.
Your boiler's fan motor is not starting, which prevents the unit from firing up to provide your home with heating or hot water.
Your boiler is failing to light because the sensor that monitors the flame is either covered in soot or has stopped working correctly.
Your boiler is not burning its fuel properly, which is causing soot to build up and could potentially lead to harmful fumes entering your home.
Your boiler is failing to start because the internal sensor responsible for lighting the flame is misaligned and cannot spark.
Your boiler is struggling to mix the right amount of air with its fuel to burn cleanly, which means it may not operate safely or efficiently.
Your boiler is struggling to stay lit reliably, causing it to periodically shut down as a safety precaution against flame or flue issues.
Your boiler has stopped working because it failed to ignite safely and has shut itself down to prevent any hazards.
Your boiler has stopped working because fuel is failing to reach the internal burner, meaning you currently have no heating or hot water.
Your boiler is making loud or unusual sounds, which usually means internal moving parts are either struggling to circulate water or starting to wear out.
Your boiler is leaking oil or fumes, which poses a serious fire and health risk and needs an expert immediately.
Your boiler is struggling to ignite smoothly because the air and fuel mixture is incorrect or there is a blockage in the flue, causing it to shudder when it starts up.
Your boiler is rapidly turning itself on and off because it cannot regulate its temperature properly, which makes it work inefficiently.
BoilerFaultCodes