31 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Heat
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Your boiler's internal computer has encountered an electronic error and is unable to communicate with its controls to provide heat.
Your boiler's internal computer brain has experienced a malfunction and can no longer communicate with the heating system.
Your boiler’s internal computer has encountered a critical electronic error and can no longer communicate with the main system.
Your boiler has experienced a fundamental software or memory error that has caused it to shut down securely for safety.
Your boiler’s internal computer has encountered a critical electronic error and can no longer control the heating system safely.
Your boiler's internal computer brain has developed an electrical fault and is unable to communicate with its own sensors.
Your boiler's internal computer has encountered a critical electronic error and can no longer control the heating system safely.
Your boiler has detected a problem with how air or water is flowing through the system and has shut down as a safety precaution.
Your boiler’s internal computer brain has developed a critical electronic fault and can no longer communicate with the rest of the system.
Your boiler's internal computer has encountered a critical electronic error and can no longer communicate with the rest of the system.
Your boiler’s internal control computer has encountered a critical electrical error and can no longer manage the system safely.
Your boiler's internal computer has encountered a critical electronic error and has stopped working to protect the system.
Your boiler's internal computer has suffered a technical malfunction and can no longer control the heating system safely.
Your boiler has experienced an internal computer error and cannot safely operate the heating or hot water until the main control parts are checked.
Your boiler's computer control board has experienced an internal electrical fault and is unable to communicate with its components.
Your boiler has detected that the internal temperature sensors have been wired or installed in the wrong positions, preventing it from heating safely.
Your boiler is not receiving enough gas to stay lit safely, which is preventing your heating and hot water from working.
Your boiler has detected that water is moving too slowly or not at all through the system, causing a heat imbalance that has triggered a safety shutdown.
Your boiler has detected a fault with its temperature sensor, which means the system cannot safely monitor the heat of the water and has stopped working as a precaution.
Your boiler has detected a fault with one of its internal temperature sensors, which is preventing the system from heating up safely.
Your boiler has stopped working because one of its internal temperature sensors has broken or become disconnected.
Your boiler has stopped working because a sensor that monitors water temperature has lost its connection or stopped sending information.
Your boiler's internal computer brain has developed a terminal electronic glitch and can no longer control the heating process safely.
Your boiler has experienced a nervous breakdown in its main computer brain, which means it cannot communicate with itself and has stopped working for safety.
Your boiler's internal computer has encountered a critical error and can no longer communicate with the rest of the system.
Your boiler's fan is failing to start or communicate with the control board, meaning the system cannot safely clear exhaust fumes to stay running.
Your boiler's fan is spinning but the control board cannot detect its speed, preventing the boiler from firing up for safety.
Your boiler has shut down because it believes the internal water pressure is too low or it is getting too hot inside.
Your boiler has shut down because the water inside it has become too hot, which is often caused by a blockage or a pump that isn't moving water through the system correctly.
Your boiler has switched itself off because the water returning to the unit is too hot, meaning the heat isn't being distributed around your home properly.
Your boiler is heating up too quickly and has shut down to prevent overheating, likely because the water isn't moving through the system properly.
BoilerFaultCodes