20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Promax Ultra Combi
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Your boiler has detected an internal sensor failure and has stopped providing hot water or heating to protect the system.
Your boiler has stopped working because its internal computer board is either the wrong version for this model or has been configured incorrectly.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, and it has likely shut down as a safety precaution.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has stopped working because the water pressure in the central heating system has dropped too low.
Your boiler is struggling to move water around the system correctly, which is causing it to shut down to prevent overheating.
Your boiler has detected that it is getting too hot inside, often because something is blocking the flow of heat or a sensor is faulty.
Your boiler has tried to light several times but cannot establish a stable flame, meaning it cannot provide heating or hot water.
Your boiler has detected that the fan, which safely removes waste gases, is not spinning at the correct speed to operate safely.
Your boiler is struggling to move water around the system correctly, which is likely caused by trapped air or a failing pump.
Your boiler's temperature sensor for the heating system has stopped communicating correctly, meaning your boiler doesn't know how hot the water is and will likely stop running for safety.
Your boiler's internal computer brain is either faulty or has been replaced with the wrong software version for your specific model.
Your boiler's hot water sensor has malfunctioned, meaning the system can no longer accurately measure the temperature of the water coming out of your taps.
Your boiler has likely overheated, causing a safety switch to trip and shut the system down to protect itself.
Your boiler has detected that the water pressure is too low for it to operate safely and has shut down.
Your boiler is struggling to move water through the system, which is causing it to stop running to prevent overheating.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot, which is a safety measure to prevent damage.
Your boiler has failed to light because it isn't receiving enough gas or cannot sense the flame.
Your boiler has detected an issue with the fan that clears exhaust fumes, preventing the system from starting for your safety.
Your boiler has detected that the water is not moving through the system quickly enough before the burner fires up.
BoilerFaultCodes