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 properly sense or circulate the water inside, causing it to shut down to prevent damage.
Your boiler is failing to start because it isn't receiving a signal to fire up or has lost its electrical connection.
Your boiler has stopped working because the mechanical fan that pushes air for the combustion process is failing to turn on.
Your boiler is failing to light because the sensor that checks for a flame is unable to see one clearly.
Your boiler is burning fuel improperly, which indicates the system is producing harmful exhaust fumes and needs an urgent inspection to prevent carbon monoxide buildup.
Your boiler is trying to start but cannot spark correctly to light the flame, which prevents it from providing any heating or hot water.
Your boiler is struggling to mix the correct amount of air and fuel during the combustion process, which could lead to unsafe fumes.
Your boiler is struggling to stay lit because it cannot reliably sense the flame or is being affected by outside wind, causing it to turn itself off for safety.
Your boiler has stopped working because it failed to light or stay lit, and it needs a professional to investigate why it cannot maintain a stable flame.
Your boiler has stopped working because it is not receiving the oil supply it needs to create a flame.
Your boiler is making loud or unusual noises, which usually suggests there is trapped air in the system or a mechanical part is starting to wear out.
Your boiler is leaking oil or fumes, which poses a serious fire and health risk and requires immediate professional attention.
Your boiler is struggling to burn fuel properly at start-up, which can cause vibrations and indicates an issue with the air supply or internal combustion settings.
Your boiler is rapidly turning itself on and off because it is struggling to regulate its temperature or is getting conflicting signals from your wall thermostat.
BoilerFaultCodes