50 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Keston Heat 80:2
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Your boiler has failed to recognize its internal software identity chip, meaning it cannot currently function or communicate with its control panel.
Your boiler’s internal computer chip has encountered a communication error or is malfunctioning, which means the unit cannot operate safely.
Your boiler thinks a flame is burning even though it hasn't been told to light yet, which stops it from starting up for safety reasons.
Your boiler has tried to light itself several times but cannot establish a flame, meaning you have no heating or hot water.
Your boiler thinks it sees a flame even though it isn't currently firing, often caused by an electrical glitch or a dirty internal sensor.
Your boiler has reached an unsafe temperature and has shut itself down to prevent damage.
Your boiler has lost power or was switched off while it was already trying to report a different fault, causing it to freeze on this error screen.
Your boiler has stopped working because the internal fan, which safely exhausts gases, is not spinning or cannot be detected by the system.
Your boiler has switched itself off because its exhaust gases have become too hot, which can be a sign of a blockage or internal damage.
Your boiler is having trouble detecting its own flame correctly, which prevents it from running for safety reasons.
Your boiler has stopped working because the internal parts that control the gas flow are not communicating correctly with the main control system.
Your boiler's main internal computer has encountered a critical error and can no longer control the heating system safely.
Your boiler has disabled itself because it cannot verify that the internal temperature sensors are measuring the correct pipes accurately.
Your boiler's internal computer has encountered a critical electronic failure and can no longer control the heating system safely.
Your boiler has detected that the water inside is getting too hot because it is not moving around your heating system properly.
Your boiler has switched itself off because the water returning to it is too hot, which usually means the water isn't moving through your radiators properly.
Your boiler has stopped working because it cannot correctly detect the water pressure, often caused by a faulty sensor or an electrical issue.
Your boiler has shut down because it keeps losing water pressure and has had to be reset too many times in a single day.
Your boiler's main internal computer has encountered a serious communication error and cannot operate safely.
Your boiler is struggling to keep a flame lit, often because the pipes that carry air in or waste water out are blocked or frozen.
Your boiler has stopped working because its internal temperature sensor has developed an electrical fault and is unable to send the correct readings.
Your boiler has lost communication with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Your boiler has detected a fault with the temperature sensor for your hot water, which means it cannot accurately tell how hot the water is.
Your boiler has detected a problem with the sensor that monitors your hot water temperature, meaning your hot water may not reach the correct temperature or might not work at all.
Your boiler has detected that the electrical supply coming from your home's mains is too low for it to operate safely.
Your boiler has detected an issue with the electrical power coming into your home, meaning the timing of the electricity supply is not stable enough for it to run safely.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water leaving the unit.
Your boiler has detected that the water pressure is too low to operate safely and has shut down to protect itself.
Your boiler's control panel has developed a technical fault with the reset button and is no longer responding to commands.
Your boiler has detected that there is too much water in the system, which can put unnecessary stress on the pipes and seals.
Your boiler’s internal computer parts are having trouble talking to each other, which prevents the unit from working.
Your boiler has stopped working because it cannot correctly measure the temperature of the water returning to the unit due to an electrical sensor fault.
Your boiler has stopped working because it cannot communicate with the part that monitors the temperature of the water returning to the unit.
Your boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Your boiler's internal display screen is having trouble talking to the main control computer, meaning the boiler cannot receive commands to turn on.
Your boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Your boiler has encountered a system error that is preventing it from firing up to provide heating or hot water.
Your boiler's internal memory chip is missing or not making a proper connection, which means the system doesn't know how to operate and has shut down.
Your boiler has detected that there is not enough water in the system to operate safely.
Your boiler is not staying lit, which means the flame is going out when it should be providing heat.
Your boiler's fan is not spinning at the correct speed or has stopped working, meaning the system cannot safely clear exhaust fumes and has shut down as a precaution.
Your boiler has stopped working because it cannot correctly detect the temperature of the water moving through the system.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning to the unit, causing it to shut down for safety.
Your boiler is having trouble communicating with the external temperature sensor that monitors the weather outside, which may cause your heating to be less efficient.
Your boiler has detected that the electricity supply coming into your home is at a lower voltage than it needs to operate safely.
Your boiler's internal computer has encountered a critical error and can no longer control the heating system safely.
Your boiler has shut down because the water inside has become too hot, often caused by a circulation blockage or a pump issue.
Your boiler was running but the flame went out unexpectedly, causing the system to shut down for safety.
Your boiler has been manually reset too many times in a short period and has temporarily locked itself out as a safety precaution.
Your boiler thinks there is a flame burning when there shouldn't be, causing it to shut down for safety purposes.
BoilerFaultCodes