38 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal computer brain is unable to talk to the front display panel, meaning the system cannot receive instructions to provide heating or hot water.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water flowing through the system due to a sensor or wiring issue.
Your boiler has stopped working because it cannot read the temperature of the water returning to it, usually due to a loose wire or a faulty sensor.
Your boiler has detected a faulty connection or sensor linked to its built-in hot water storage tank, meaning your hot water supply may be affected.
Your boiler has detected a faulty connection or sensor inside the built-in hot water storage tank, which means your hot water supply may be affected.
Your boiler has temporarily stopped working because a temperature sensor inside the unit is giving a false reading due to an electrical short.
Your boiler has detected a faulty temperature reading on its internal water return pipe, which causes it to safely shut down to prevent damage.
Your boiler has detected an electrical short-circuit in the sensor that monitors the built-in hot water storage tank.
Your boiler has detected an electrical short circuit related to the hot water storage tank temperature sensor.
Your boiler has detected that it is running too hot and has automatically shut down to prevent any damage or danger.
Your boiler has temporarily stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has stopped working because it has detected a major difference in water temperature between the pipes going out and coming back, usually due to a circulation problem.
Your boiler has shut down because the internal water is getting too hot too quickly, usually caused by low water pressure or trapped air stopping the water from flowing properly.
Your boiler has detected an internal electrical connection issue within its main heating module, meaning it has temporarily shut down for safety.
Your boiler is safely shutting down because it cannot accurately detect whether the burner flame is actually lit.
Your boiler is trying to start up, but it is failing to ignite because it is not getting the right gas supply or spark.
Your boiler tried to stay lit, but the flame went out and it couldn't restart because the gas supply was interrupted or it couldn't detect the flame properly.
Your boiler has detected that the internal fan responsible for safely clearing exhaust gases is not spinning correctly.
There is a communication error between your boiler and its controls, often caused by an electrical wiring fault or a heavy load on the internal data connection.
Your boiler has detected an electrical fault with the internal valve that controls the gas supply, meaning it has safely shut down to prevent any risk.
Your boiler has detected a potential issue with the internal gas valve failing to shut off properly, which requires immediate attention from a qualified professional for safety reasons.
Your boiler has encountered an internal memory error, meaning the main computer system is failing to read its operating data correctly.
Your boiler has detected an issue with its internal temperature sensors or its main electronic brain.
Your boiler’s internal computer has overheated, causing it to shut down to prevent permanent damage.
Your boiler's main control board is receiving an incorrect electrical signal from the flame sensor, meaning the system cannot safely confirm if the burner is lit.
Your boiler's computer system is confused because replacement parts were recently fitted without being properly programmed.
Your boiler has temporarily stopped working because a sensor that measures water temperature is giving a faulty reading.
Your boiler is temporarily shutting down because it is receiving conflicting temperature readings from its internal water sensors.
Your boiler's water pressure sensor is failing to read correctly, meaning it cannot accurately check the pressure of the system.
Your boiler has detected that the internal water pressure reading is too high due to a sensor or electrical fault.
Your boiler has noticed that the water pressure does not jump up as expected when the internal pump starts, usually due to low water pressure, trapped air, or a faulty sensor.
Your boiler has shut down because a safety sensor detected that the main part of the boiler has become too hot.
Your boiler has temporarily stopped working because it has detected an issue with the device that removes wastewater or the safety flap connected to your flue.
Your boiler has detected that an incompatible control accessory has been wired into the system incorrectly.
Your boiler has detected a faulty connection or wiring issue with one of its internal temperature sensors.
Your boiler has detected a problem with how water is being pumped and heated inside its built-in hot water storage tank.
Your boiler has temporarily lost communication with its hot water storage tank module, which usually points to a loose wire or a temporary electronic glitch.
Your boiler is receiving an incorrect temperature reading from its internal hot water storage tank sensor, which stops it from working properly.
BoilerFaultCodes