55 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost its connection to the solar panel temperature sensor, meaning it cannot monitor how much heat is coming from your solar system.
Your boiler has lost connection with one of its temperature sensors, meaning it cannot accurately monitor the water temperature to operate efficiently.
Your boiler has lost its connection to the sensor that monitors the temperature of your hot water cylinder, meaning it cannot properly manage your hot water supply.
Your boiler has lost communication with the solar heating system or has detected a fault within the solar control unit.
Your boiler's outside temperature sensor has developed an electrical fault, causing the system to behave as if it is exactly 0°C outdoors regardless of the actual weather.
Your boiler has lost connection to its outdoor sensor, causing it to think it is freezing outside and potentially making your radiators warmer than necessary.
Your boiler has lost its connection to the temperature sensor that monitors the main water flow, likely due to a faulty electrical component or sensor.
Your boiler has lost connection with a temperature sensor that monitors the main water flow, meaning it cannot accurately regulate how much heat to send to your radiators.
Your boiler has stopped working because its internal temperature gauge has failed, causing the system to lock the burner for safety.
Your boiler has stopped working because it can no longer accurately measure its own internal temperature due to a broken wire or faulty sensor.
Your boiler has detected a technical fault with a sensor on one of your heating zones, which means that specific part of your heating will likely shut down to prevent damage.
Your boiler has lost communication with a temperature sensor in your secondary heating zone, causing that specific circuit to shut down as a safety precaution.
Your boiler is unable to heat your water because the temperature sensor for your hot water cylinder has failed or has a wiring fault.
Your boiler is unable to heat your hot water cylinder because it has detected a faulty or short-circuited temperature sensor.
Your boiler is unable to heat your water because the sensor that monitors your hot water cylinder temperature has lost its electrical connection.
Your boiler is unable to provide hot water because it has lost its connection to one of the sensors that monitors the temperature inside your hot water tank.
Your boiler has detected a fault with the sensor that monitors the temperature of your solar panels, meaning the solar heating system will not work correctly.
Your boiler has detected a technical fault with a sensor in your solar heating system, which means your solar panels may not be contributing to your hot water as they should.
Your boiler has detected a fault with the sensor that monitors the temperature of your solar hot water tank, meaning your solar thermal system may not heat your water correctly.
Your boiler's control panel has lost communication with the internal computer, making it difficult or impossible to adjust your heating settings.
Your boiler has stopped working because it has detected an electrical fault with the sensor that monitors the safety of your exhaust gases.
Your boiler's main control panel is having trouble talking to the internal computer, meaning you cannot adjust settings or operate the unit correctly.
Your boiler has encountered an internal electronic error while trying to process sensor data, which is preventing it from running properly.
Your boiler has experienced an internal communication error or software glitch within its main electronic control unit.
Your boiler's internal computer chip is either missing, faulty, or not communicating correctly with the main controls, meaning the unit cannot start for safety reasons.
Your boiler has stopped working because it can no longer safely monitor the temperature of the exhaust gases leaving the system.
Your boiler has lost communication with the control box that manages your second heating zone, meaning your underfloor heating or additional radiators may not warm up correctly.
Your boiler has lost its connection with the remote control thermostat for your main heating circuit, meaning it cannot receive instructions on when to turn the heating on.
Your boiler has lost communication with the remote control unit that manages your second heating circuit, meaning that part of your home may not heat correctly.
Your boiler is having trouble communicating with your wall-mounted room thermostat because the settings weren't configured correctly during installation or after a power cut.
Your boiler's internal communication component is either missing, faulty, or not recognised by the main control system.
Your boiler is having trouble talking to the solar heating system, meaning your solar panels may not be contributing to your hot water as they should.
Your boiler is struggling to communicate with its internal pump, which means it cannot properly move heated water around your system.
Your boiler is having trouble communicating with the internal pump that moves water around your second heating zone, which may prevent some of your radiators from getting hot.
Your boiler is having trouble communicating with the internal pump that moves water around your radiators, meaning your heating may not work correctly.
Your boiler has lost its connection with the remote control or internet communication module, which may stop you from controlling your heating via an app or external thermostat.
Your boiler is having trouble 'talking' to an external accessory, such as an extra heating controller or a smart home module.
Your boiler's internal communication system has failed, meaning the main control board cannot talk to its connected expansion modules.
Your boiler has lost its connection to the indoor temperature sensor for your main heating zone, meaning it cannot accurately judge how warm your home is.
Your boiler has lost signal from the temperature sensor that controls your second heating zone, meaning it cannot correctly regulate the warmth in that specific part of your home.
Your boiler has lost connection with the sensor that monitors the temperature for your second heating zone, meaning it cannot accurately heat that specific area of your home.
Your boiler has detected an issue with its incoming electrical power supply, meaning it isn't getting the steady voltage it needs to operate safely.
Your boiler is struggling to detect a flame correctly, causing it to shut down for safety purposes.
Your boiler is struggling to breathe because the pipe that vents exhaust gases outside or brings fresh air in is obstructed.
Your boiler's main internal computer has developed a serious electronic failure and can no longer communicate with the rest of the system.
Your boiler has automatically shut down because its exhaust gases have reached an unsafely high temperature, which is often caused by a blockage or a lack of water circulation.
Your boiler has switched itself off because it has reached a dangerous temperature and triggered a safety cut-out to prevent overheating.
Your boiler detects a flame before it has even started the ignition process, which is a safety conflict that prevents it from firing up.
Your boiler is failing to light the flame properly, meaning it cannot provide heating or hot water for your home.
Your boiler has detected a problem with internal pressure readings, which means it cannot safely confirm the correct flow of air for combustion.
Your boiler has detected that the fuel supply is not shutting off as quickly as it should, causing it to shut down for safety.
Your boiler is failing to start because the internal fan is not spinning at the correct speed to safely clear the exhaust gases.
Your boiler has detected that the fan is spinning faster than it should during the start-up sequence, preventing the burner from lighting safely.
Your boiler's internal computer has detected a fault with the control system that manages the burner, preventing it from heating your home or water.
Your boiler's electronic control system is experiencing electrical interference or a hardware internal communication error, preventing it from operating.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes