17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that a flame is present when it should be switched off, which is a safety concern that requires an immediate professional check.
Your boiler is unable to safely vent exhaust gases because the internal fan that pushes air through the system has stopped working correctly.
Your boiler is failing to light the internal burner, so it has safely shut itself down to prevent a gas build-up.
Your boiler has detected an issue with the air or exhaust system, meaning it cannot safely push fumes outside, so it has shut down to protect you.
Your boiler has stopped working because its internal computer cannot send the necessary instructions to the gas supply mechanism.
Your boiler has locked itself for safety because it was reset too many times while trying to clear a previous error.
Your boiler is struggling to detect the temperature of the water coming out of your hot taps, which means it may fail to provide consistent hot water.
Your boiler is temporarily shutting down because it is not receiving enough electricity from your home's power supply.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler is struggling to read the outdoor temperature, so it is defaulting to a standard internal setting until the sensor is fixed.
Your boiler has detected that water is heating up too quickly compared to the sensors' expectations, causing it to shut down to prevent damage.
Your boiler has detected that the heat exchanger is getting too hot, likely due to a lack of water flow, triggered to prevent potential damage to the internal components.
Your boiler has detected an internal calibration error with its gas and air mixture, meaning it cannot safely regulate its combustion and has locked out to prevent damage.
Your boiler has detected an internal communication error with its main control unit, causing it to shut down safely for your protection.
Your boiler's internal computer has failed to start up correctly, which means it cannot operate your heating or hot water systèmes.
Your boiler is currently in a setup or diagnostic mode because a programming key has been left plugged into its internal control board.
Your boiler is having trouble communicating with an internal memory chip, which usually means the system's brain needs to be reset or reconfigured by a qualified professional.
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BoilerFaultCodes