36 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your electric boiler has stopped working because it has detected an internal fault and has automatically shut down for safety.
Your boiler has tried to start several times but failed to light, causing the system to lock itself out for safety.
Your boiler's internal computer is having trouble processing signals from its sensors, which has caused the system to stop working for safety.
Your boiler's internal computer has encountered a memory error and can no longer process data correctly.
Your boiler is repeatedly failing to keep a steady flame going and has locked itself out for safety.
Your boiler has stopped working because its internal thermometer has developed an electrical fault and can no longer monitor the water temperature accurately.
Your boiler has lost its connection with the internal temperature sensor that monitors the main heating output, meaning it can't tell how hot the water is.
Your boiler has stopped providing hot water because the internal sensor used to monitor water temperature has developed an electrical fault.
Your boiler has detected that the electricity supply coming into your home is too low for it to operate safely and correctly.
Your boiler has stopped working because the water level inside the heating system has dropped too low.
Your boiler has detected too much water pressure in the system, which can cause the safety valve to leak or the unit to stop working.
Your boiler has stopped working because it cannot detect any water pressure, which means it has shut down to protect itself from damage.
Your boiler has detected an electrical fault with the internal sensor that monitors exhaust gases, causing the system to shut down for safety.
Your boiler has stopped working because it cannot communicate with the sensor that monitors the safety of the exhaust gases.
Your boiler has stopped working because it can no longer detect the water pressure level inside the system.
Your boiler has failed to light after several attempts and has locked itself out for safety.
Your boiler has detected a flame when it shouldn't be there, causing the system to shut down for safety purposes.
Your boiler has switched itself off because it has reached an unsafe temperature to prevent damage to the internal components.
Your boiler has detected that the internal fan is not spinning correctly, which means the system cannot safely clear away waste gases to start the heating process.
Your boiler is failing to detect the flame it needs to stay on, meaning it cannot safely generate heat for your home.
Your boiler has stopped working because its internal control system is not receiving the correct return signal from a control valve or motor.
Your boiler's internal computer memory has encountered a data error, which has caused the system to shut down for safety.
Your boiler has sensed that one of its temperature monitors is giving an unreliable reading, so it has shut down as a safety precaution.
Your boiler has detected that a temperature sensor is stuck or giving an incorrect reading, causing the system to stop running for safety.
Your boiler's electronic control board has detected a memory or processing error and has shut down as a safety precaution.
Your boiler's temperature sensor responsible for monitoring water returning to the unit has stopped working correctly.
Your boiler has shut down because the electrical supply voltage is too low for it to operate safely.
Your boiler's internal thermometer that measures water temperature has stopped reporting correctly, preventing the system from heating up properly.
Your boiler has detected a problem with the sensor that monitors internal temperatures and exhaust gases, causing the system to shut down for safety.
Your boiler has shut itself down for safety after too many unsuccessful attempts were made to restart it remotely or via the control panel.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has too much water inside it, which might cause it to shut down for safety or leak from the pressure relief valve.
Your boiler has stopped working because it cannot detect the sensor that monitors water pressure inside the system.
Your boiler is having trouble measuring the temperature of your hot water, which means your taps and showers may not get warm.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot.
Your boiler has detected a general internal malfunction and has shut down as a safety precaution, meaning you currently have no heating or hot water.
BoilerFaultCodes