58 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Duo-tec 2 Combi
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Your boiler has stopped working because it has failed to ignite, which means you currently have no heating or hot water.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has detected an issue with the ventilation system that clears away exhaust gases, so it has safely shut down to prevent any risk.
Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water until the issue is resolved.
Your boiler is not firing up properly, which means it cannot light the gas to provide heat or hot water.
Your boiler is struggling to accurately measure the temperature of the water used for your radiators, causing it to stop heating to prevent internal damage.
Your boiler is currently unable to read the temperature of the water flowing through it, so it has shut down to prevent overheating.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, causing the system to stop working as a precaution.
Your boiler is having trouble communicating with the part that controls the gas supply, so it has safely shut itself down to prevent any issues.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal components.
Your boiler is struggling to detect water flow or pressure, so it has safely shut itself down to prevent damage.
Your boiler's safety sensor is stuck, which prevents it from starting because it cannot confirm that the fan is working correctly.
Your boiler is having trouble communicating with the part that controls the gas flow, meaning it cannot light the burner to provide heat or hot water.
Your boiler is currently topping itself up with water automatically and is simply waiting for the process to complete before it resumes normal heating.
Your boiler has detected that the water pressure in your system is incorrect and it cannot safely maintain the correct level.
Your boiler has lost the ability to accurately measure the water temperature for your central heating, so it has shut down to prevent overheating.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, meaning it has shut down as a precaution to ensure it is operating safely.
Your boiler's temperature sensor is providing faulty readings, so the system has shut down to prevent overheating or operating inefficiently.
Your boiler has lost the digital connection to its control panel or remote thermostat, preventing it from receiving instructions to heat your home.
Your boiler has detected that limescale buildup is affecting the sensor that monitors your hot water flow, which may lead to lukewarm water or inconsistent temperatures.
Your boiler has detected a flame signal when it is not supposed to be running, which forces the system to shut down as a safety precaution.
Your boiler is currently unable to read the temperature of the water returning to it, which prevents it from heating your home or water safely.
Your boiler is struggling to accurately detect the temperature of the water it is heating, so it has shut down to prevent the system from overheating.
Your boiler is struggling to breathe properly because the exhaust pipe outside might be blocked or the gas is not burning correctly, causing the system to shut down for safety.
Your boiler has lost its fine-tuning and needs to undergo a self-calibration process to ensure the gas and air are burning efficiently.
Your boiler has lost the ability to measure the water pressure accurately, which has caused it to stop running for safety.
Your boiler's main computer has encountered an internal error and cannot communicate with the system to operate correctly.
Your boiler has failed to calibrate its internal settings correctly during a self-check of the gas and air mixture.
Your boiler is struggling because the electrical voltage being supplied to it is lower than it needs to be to operate correctly.
Your boiler is struggling to move water around the system effectively, which is causing it to shut down to prevent overheating.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent any damage or safety hazards.
Your boiler has detected that there is too much water pressure in the system, which can cause it to shut down for safety.
Your boiler has stopped working because the water pressure in the system has dropped too low.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to pump water around your heating system effectively, so it has shut down to prevent damage from overheating.
Your boiler started to heat up but the flame went out unexpectedly while it was running.
Your boiler has lost its flame while trying to automatically adjust its settings for efficient burning.
Your boiler has detected that the flue gases are getting too hot, so it has safely shut itself down to prevent any damage.
Your boiler has detected that the electricity supply was cut off while it was trying to protect itself from overheating or circulation issues.
Your boiler is failing to ignite because it is not receiving enough gas or cannot detect a flame.
Your boiler's internal computer has encountered a software glitch or a communication error that is preventing it from running properly.
Your boiler's computer has detected an internal error and has shut down as a safety precaution.
Your boiler’s internal computer has encountered a memory error and cannot safely manage the heating process, meaning it has shut down to protect itself.
Your boiler is signalling that the reset button has been pushed even though no actual error has been detected.
Your boiler has detected that water is not circulating correctly through the system, often due to a pump issue or a blockage.
Your boiler has detected that the fan, which is essential for safely venting exhaust gases, is not operating correctly and has shut itself down to keep you safe.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning at the correct speed.
Your boiler’s internal computer has encountered a serious communication error and has safely shut down to prevent further issues.
Your boiler has lost the ability to measure how much water is inside its system because a sensor has become disconnected or faulty.
Your boiler has detected a brief power interruption or an internal electronic glitch that has caused the system to stop working safely.
Your boiler has detected trapped air bubbles that are preventing the water from circulating correctly, causing it to shut down to protect itself.
Your boiler has detected that it is overheating because water is not moving through the system properly.
Your boiler has detected an issue with the electrical frequency coming from the mains power supply or a fault within its own internal control board.
Your boiler has detected a problem with the sensor that monitors hot water temperature, which may mean you have no hot water or the temperature is inconsistent.
Your boiler thinks it sees a flame even though the gas supply should be turned off, which is a safety conflict that prevents the system from starting.
Your boiler has stopped working because it isn't receiving enough electrical power from the mains supply to run safely.
Your boiler is currently running a brief self-diagnostic calibration test, which is a normal process after recent adjustments or a power cycle.
BoilerFaultCodes