55 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost connection with a temperature sensor for one of your heating zones, meaning that specific area may not heat up correctly.
Your boiler has lost communication with the solar panel sensor on your roof, meaning it cannot monitor or use solar energy to heat your water.
Your boiler has lost connection with the sensor that monitors the temperature of the solar hot water cylinder, meaning it cannot properly manage your solar-heated water.
Your solar heating system has stopped circulating fluid properly or has become too hot, meaning your solar panels won't help heat your water right now.
Your boiler has lost communication with the solar heating control unit, meaning your solar panels won't be helping to heat your water right now.
Your boiler is struggling to accurately read the outdoor temperature, which means your heating might not adjust correctly to the weather outside.
Your boiler has lost its connection to the sensor that measures the temperature outside, meaning it may not know how hard it needs to work to heat your home.
Your boiler has lost its wireless connection to the sensor that measures the temperature outside, which may cause your heating to be less efficient.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water being sent to your radiators.
Your boiler has lost connection with its main internal temperature sensor, meaning it cannot accurately monitor the water temperature to heat your home.
Your boiler has detected a fault with the sensor that measures water temperature, causing the system to shut down for safety.
Your boiler has stopped working because it cannot accurately measure the temperature of the water inside the system.
Your boiler has detected an electrical connection problem with the sensor that controls the temperature for your second heating zone, such as underfloor heating or a separate radiator circuit.
Your boiler has detected an electrical fault with a sensor that controls the temperature for a specific part of your heating system, which may prevent that area from warming up properly.
Your boiler has lost communication with the temperature sensor for your secondary heating zone, meaning it can no longer accurately control the warmth of that specific area.
Your boiler has stopped heating up your hot water because a sensor that monitors the temperature in your storage tank has failed.
Your boiler has stopped heating your water because the sensor responsible for checking the temperature of the hot water leaving the unit has failed.
Your boiler is unable to heat your hot water because it has lost its connection to the temperature sensor inside the water storage cylinder.
Your boiler has stopped producing hot water because a sensor responsible for monitoring the water temperature has broken or disconnected.
Your boiler has detected a faulty electrical connection or a technical issue with the sensor that monitors the temperature of your solar panels.
Your boiler has detected a technical fault with the sensor that monitors the temperature of your solar water cylinder, which may affect how your hot water is heated by the sun.
Your boiler has detected that the water pressure in the system has dropped too low to operate safely, causing it to shut down to prevent damage.
Your boiler has detected that a temperature probe inside the flue system has shifted from its correct position and needs to be physically reset.
Your boiler has detected that the water pressure inside your heating system has become too high, which can put unnecessary strain on the internal components.
The control panel that manages your boiler's settings is having a communication error, meaning your heating and hot water controls will likely not work until it is reset or repaired.
Your boiler has detected that water is struggling to flow through the system properly, which may be due to trapped air or a blockage.
Your boiler has detected that the internal water pump is not working correctly, which prevents heat from moving around your home.
Your boiler has detected a faulty electrical signal from the sensor that monitors the temperature of the exhaust fumes, causing the system to stop working as a safety precaution.
Your boiler's control panel is struggling to communicate with the main internal computer, which is preventing the system from operating correctly.
Your boiler has detected an internal electronic error that is preventing it from operating correctly.
Your boiler has detected an internal electronic error that is preventing it from operating safely and reliably.
Your boiler's computer is having trouble reading the configuration card that tells it how to operate correctly.
Your boiler has detected a disconnected wire or a faulty sensor in the flue system, which prevents it from safely monitoring exhaust gases.
Your boiler is having trouble 'talking' to an add-on control unit, which means it may not be managing your heating or hot water zones correctly.
Your boiler is having trouble communicating with the solar panel controls, which may mean your solar hot water heating system is not currently working.
Your boiler is having trouble 'talking' to an accessory unit that manages extra features like additional heating zones or solar equipment.
Your boiler is having a communication problem with its smart control system, which means it cannot properly share information between the thermostat and the heating unit.
Your boiler is having trouble communicating with the internal water pump, which means it cannot circulate heat effectively around your home.
Your boiler has lost communication with an external accessory, such as a solar thermal controller or an additional heating control module, which is preventing the system from operating correctly.
Your boiler has detected that an external accessory connected to it, such as a heating zone controller or a sensor, is reporting an error signal.
Your boiler has detected an external signal or safety switch connected to it that is currently reporting an error, meaning the system has paused to prevent operation until the external issue is resolved.
Your boiler is struggling to accurately measure its own flame quality during a self-check, which prevents it from firing up safely.
Your boiler is currently performing an internal self-check to ensure it is burning gas safely and efficiently.
Your boiler has detected an issue with the internal electrical power supply, which is preventing it from operating correctly.
Your boiler is failing to confirm that the burner flame has ignited, so it has safely shut down to prevent gas from escaping.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler is struggling to detect the flame needed to heat your home, so it has safely shut down to prevent any issues.
Your boiler is struggling to confirm that the internal flame has successfully ignited, so it has safely shut down to prevent gas buildup.
Your boiler has detected an internal electronic error that is preventing it from operating safely and reliably.
Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has detected that it is overheating and has automatically shut itself down to prevent damage.
Your boiler has detected a flame signal when it is not supposed to be lit, which acts as a safety lockout to prevent potential issues with the ignition process.
Your boiler's internal sensor that detects how much water is inside the system is currently failing to send a signal, which stops the boiler from operating to prevent potential damage.
Your boiler has detected an issue with the internal gas control system where the fuel supply is not shutting off as quickly as it should during the safety shutdown process.
Your boiler has detected that the internal fan responsible for safely removing exhaust gases is not operating correctly, so it has shut down to keep your home safe.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes