19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Genus ONE Net
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Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent any damage or safety issues.
Your boiler has detected that water is not moving through the system correctly, which is preventing it from heating your home or water safely.
Your boiler has detected that water is not moving through the system properly, which is causing it to shut down to prevent overheating.
Your boiler's air extraction system is not working correctly, which prevents the unit from starting safely.
Your boiler has detected a software or internal communication error with its main brain, meaning it has safely shut down to prevent incorrect operation.
Your boiler has stopped working because it is unable to accurately read the temperature of the water leaving the system.
Your boiler has detected a faulty electrical signal from its internal temperature reading component, meaning it has switched itself off to prevent overheating or incorrect operation.
Your boiler has detected that the temperature in your underfloor heating system is too high and has safely shut down to prevent damage.
Your boiler is mistakenly detecting a flame when it shouldn't be, which is a safety mechanism preventing it from starting up normally.
Your boiler's internal computer has encountered a critical software or communication error and has safely shut itself down to prevent further damage.
Your boiler is struggling to accurately measure the temperature of the water flowing into and out of your heating system, so it has stopped working as a safety precaution.
Your boiler has detected a series of internal faults and has locked itself down for safety reasons after multiple failed attempts to function.
Your boiler failed to light on its first try and needs a quick reset to attempt to restart the burner.
Your boiler is struggling to detect the temperature of your hot water supply, so it has stopped providing hot water to prevent it from overheating.
Your boiler is having trouble detecting the temperature of the water it is trying to heat for your taps and shower.
Your boiler is struggling to read the temperature of the water in your separate hot water cylinder, which may result in no hot water or an inability to regulate its temperature.
Your boiler is having trouble 'talking' to the temperature sensor inside your hot water tank because of an electrical wiring or component issue.
Your boiler has detected that the water temperature in your hot water storage tank has risen dangerously high and has shut itself down to prevent damage.
Your boiler's wall-mounted thermostat control is unable to communicate with its temperature sensor, which is causing it to stop the heating system from working as intended.
BoilerFaultCodes