25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Combi
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Your boiler has detected a problem with the fan that safely removes exhaust gases, meaning it will not fire up for heating or hot water until it is repaired.
Your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, causing it to shut down as a safety precaution.
Your boiler has detected an electrical fault within the ignition system, preventing it from safely lighting the flame.
Your boiler has detected that a sensor monitoring the temperature of the exhaust gases is not working correctly, causing the system to shut down for safety.
Your boiler has detected an electrical wiring issue where the live and neutral connections are reversed, preventing it from starting for safety reasons.
Your boiler is unable to safely move air through its system, so it has shut down to prevent any unsafe conditions.
Your boiler has lost the ability to accurately measure the water temperature, so it has shut down to prevent overheating.
Your boiler is having trouble measuring the temperature of the water returning to it, which causes it to stop working as a safety precaution.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, which will likely prevent you from getting hot water.
Your boiler has detected that the temperature monitoring system for the exhaust gases is not reading correctly, which means the boiler will stop working to ensure safety.
Your boiler has detected an issue with the flame during operation, causing it to shut down for safety.
Your boiler's electrical power supply has been connected with the live and neutral wires swapped, which is preventing the system from detecting the flame safely.
Your boiler's temperature sensor is reporting an inconsistent or faulty reading, causing the system to stop working as a safety precaution.
Your boiler has detected a serious internal system error that requires a professional engineer to investigate.
Your boiler has detected an internal communication error and has safely shut itself down as a precaution.
Your boiler has detected a critical internal error that prevents it from starting until a qualified heating engineer resets or repairs the system.
Your boiler's main control unit has identified an internal electronic error and has shut down for safety to prevent unpredictable system behaviour.
Your boiler has detected a communication breakdown between its internal computer and the main control board, preventing it from functioning correctly.
Your boiler has detected a serious communication error between its internal parts and has automatically shut down to prevent damage.
Your boiler has detected an issue with the internal air circulation system, meaning it cannot safely clear waste gases and has shut down to prevent risk.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage or safety issues.
Your boiler's main computer control panel has detected an internal error, which means the system has safely shut down to prevent damage.
Your boiler is failing to light the flame or keep it running, which means it has safely shut itself down to prevent gas from building up.
Your boiler has safety-shut itself down because it detected that the water inside has become dangerously hot.
Your boiler is failing to ignite the internal flame, which means it cannot produce any hot water or heating.
BoilerFaultCodes