50 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Keston Heat 55 2
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Your boiler has failed to recognize its internal identity chip, preventing it from starting up correctly.
Your boiler's identity card has stopped communicating with the main control board, preventing the system from operating.
Your boiler thinks it sees a flame even though it hasn't tried to light yet, which is causing it to shut down for safety.
Your boiler has tried to light several times but cannot start, which means you currently have no heating or hot water.
Your boiler thinks a flame is burning even when it shouldn't be, which is preventing it from starting up safely.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent internal damage.
Your boiler has lost power or been turned off while it was already trying to report a different fault, causing it to freeze in its lockout state.
Your boiler has stopped working because the internal fan, which safely pushes exhaust gases out of the flue, is not spinning correctly.
Your boiler has shut down because the internal exhaust gases are getting too hot, indicating that heat is not being transferred correctly into your home's water system.
Your boiler is having trouble detecting the flame used to heat your water, which is causing the system to shut down for safety.
Your boiler has detected an internal electrical problem with the parts that control the gas flow, meaning it cannot ignite for safety reasons.
Your boiler's internal computer has encountered a critical electronic failure and cannot safely manage the heating process.
Your boiler has stopped working because its internal sensors are reporting conflicting temperature readings from your pipework.
Your boiler's main internal computer has encountered a critical error and is unable to manage the heating process safely.
Your boiler has detected that the water inside is getting too hot because it is not moving around your heating system quickly enough.
Your boiler has shut down because the water returning to it is too hot, which usually means the water isn't moving through your radiators properly.
Your boiler is having trouble detecting or maintaining the correct water level needed to operate safely.
Your boiler has shut down because it keeps losing water pressure and needs a top-up or has a leak that needs investigation.
Your boiler's internal computer has encountered a critical error and can no longer safely manage the heating process.
Your boiler has started an ignition but the flame has unexpectedly gone out, causing the system to shut down for safety.
Your boiler has stopped working because its internal computer has lost communication with the sensor that monitors water temperature leaving the unit.
Your boiler has lost communication with the internal sensor that monitors the temperature of the water leaving the unit, causing it to stop running for safety.
Your boiler has detected a fault with the sensor that monitors your hot water temperature, meaning it cannot safely heat your water.
Your boiler has detected a technical fault with the sensor that monitors your hot water temperature, meaning it cannot provide hot water safely.
Your boiler has detected that the electricity supply coming into your home is too weak for it to operate safely.
Your boiler is struggling to operate because it detects an inconsistency in the electricity supply entering your home.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water leaving the unit.
Your boiler has stopped working because the water pressure inside the system is too low.
Your boiler's control panel has developed an internal electrical fault and is no longer responding to the reset button.
Your boiler has detected that there is too much water pressure in the system, which can cause internal leaks or damage if not reduced.
Your boiler's main control panel has lost contact with the internal computer that runs the system, preventing it from starting up.
Your boiler has stopped working because it cannot correctly read the temperature of the water coming back into the system.
Your boiler has lost communication with the sensor that monitors the temperature of the water coming back from your radiators, causing the system to stop working for safety.
Your boiler has stopped working because it cannot correctly read the temperature of the exhaust gases, usually due to a faulty electrical connection or sensor.
Your boiler's main control panel is having trouble talking to the internal 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 it to shut down for safety.
Your boiler has encountered a critical system error that has forced it to shut down to prevent damage or safety issues.
Your boiler's computer memory card is missing or not making a proper connection, which means the system doesn't know how to operate.
Your boiler has detected that the water pressure inside the system has dropped too low to operate safely.
Your boiler has started to light but the flame has gone out, meaning the system has shut down as a safety precaution.
Your boiler's internal fan, which safely pushes exhaust gases out of the flue, is not spinning correctly and the system has shut down for safety.
Your boiler has detected that water is not circulating correctly or the sensors that measure temperature are failing, causing the system to shut down for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators, preventing it from heating correctly.
Your boiler has lost connection with the sensor that measures the temperature outside, which may cause your heating to work less efficiently or run at the wrong temperature.
Your boiler has detected that the electricity supply from the mains is too low for it to operate safely and correctly.
Your boiler's main internal computer has developed a fault and is unable to control the heating system correctly.
Your boiler has shut down because the internal water temperature has become too hot.
Your boiler has lost its flame during operation, meaning it can no longer safely heat your water or radiators.
Your boiler has been manually reset too many times in a short period and has locked itself out as a safety precaution.
Your boiler thinks there is a flame present when there shouldn't be one, so it has shut down for safety purposes.
BoilerFaultCodes