66 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost the connection to the temperature sensor on your solar panels, meaning it cannot properly read how much solar energy is available.
Your boiler has lost the connection to the hot water storage sensor connected to its solar control system, meaning it cannot properly monitor your stored hot water temperature.
Your solar thermal or collector system is not detecting enough water flow, or a safety limit switch has tripped.
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 has lost the connection to the sensor that measures the temperature of your hot water tank, meaning it cannot accurately heat your water.
Your boiler has lost the connection to the sensor that measures how hot your water is, meaning it cannot safely regulate the temperature.
Your boiler has detected an electrical fault with the sensor that monitors your solar panel water temperature.
Your boiler has detected a faulty electrical connection related to the hot water cylinder temperature sensor for the solar system.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
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 water pump which moves heat around your home is stuck or unable to spin freely, causing the heating system to stop working.
Your boiler has detected an electrical fault in the sensor that monitors the temperature of the gases leaving your flue, meaning the boiler has safely shut down to prevent potential damage.
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 monitoring the temperature of the exhaust gases, causing it to shut down for safety reasons.
Your boiler has lost connection to the extra control unit responsible for managing your second heating zone, meaning that specific part of your heating system cannot be controlled properly.
Your boiler has lost communication with an extra heating zone controller, which means one specific part of your underfloor or zoned heating system may not respond properly.
Your boiler has temporarily lost its connection to the main room thermostat controller, meaning it cannot properly receive temperature commands for your heating.
Your boiler has lost communication with the remote control or thermostat for your second heating zone, meaning that specific part of your heating system cannot take instructions properly.
Your boiler has lost communication with one of its remote room thermostats, which means that particular heating zone cannot be controlled properly.
Your boiler is having trouble communicating with an optional external control system, which usually means a link device is not connected correctly or has developed a fault.
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 has temporarily lost communication with its built-in solar water heating controller, though your standard heating and hot water should continue to work.
Your boiler has lost communication with an optional control module that manages external heating components like extra zones or solar pumps.
Your boiler is struggling to talk to its external controls or internal smart settings, which means it doesn't know when to turn on or off.
Your boiler has lost its connection to the remote control or internet monitoring system, so you may not be able to adjust settings via your app or external thermostat.
Your boiler's internal computer parts have temporarily lost connection with each other, causing the system to stop working.
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 has lost its connection to the indoor temperature sensor for your main heating area, meaning it cannot accurately tell how warm your rooms are.
Your boiler has detected an electrical wiring issue with the temperature sensor on your second heating zone.
Your boiler has detected an electrical fault in the temperature sensor for one of your specific heating zones, which may cause that part of the house not to heat properly.
Your boiler is temporarily unable to read the temperature of your main heating area because a connection to its temperature sensor has come loose or broken.
Your boiler has lost connection to a temperature sensor used for your second heating zone, meaning that part of your home may not heat properly.
Your boiler has lost the connection to the temperature sensor for one of your heating zones, meaning it is running without room temperature guidance.
Your boiler's main computer has temporarily lost communication with an external heating control or add-on module.
Your boiler has temporarily stopped working because the flame detector sensed an irregular signal during its internal self-check.
Your boiler has detected that it is getting too hot inside because the heat isn't moving away properly, so it has safely shut down to prevent damage.
Your boiler has temporarily stopped working because it has detected an issue with the internal electrical power supply and cannot safely ignite the burner.
Your boiler has temporarily stopped working because it cannot safely detect the burner flame.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler has temporarily stopped working because it cannot properly detect the flame inside, which prevents it from safely igniting.
Your boiler has stopped working because it cannot detect a stable flame inside the burner.
Your boiler has failed to ignite or stay lit because it cannot properly detect the burner flame, so it has safely shut itself down to prevent any risk.
Your boiler has temporarily stopped because it is having trouble detecting the flame properly or managing its gas and exhaust supply safely.
Your boiler has stopped working because it has detected an internal control error while trying to calibrate its burner.
Your boiler has detected an internal electronic error and has safely shut itself down to prevent further issues.
Your boiler has detected an issue with its internal ignition control system and has safely stopped working to prevent any risk.
Your boiler is trying to light, but the flame keeps going out immediately, which usually indicates an issue with the gas supply or the flame detection.
Your boiler has detected an internal error that has forced it to safely shut down, meaning it is currently unable to provide heating or hot water.
Your boiler has temporarily stopped working because it detected that the exhaust gases coming out of the flue got too hot, acting as a safety precaution.
Your boiler has safely shut down because it has detected an overheating risk inside the system.
Your boiler has detected a flame signal before it has even tried to light, which stops it from starting up safely.
Your boiler has lost connection to its water pressure monitor, meaning it cannot accurately check the system pressure.
Your boiler has detected an issue with the gas safety valve closing properly, which means the system has safely locked itself out to prevent any risk.
Your boiler has detected an issue with the internal fan that safely pushes waste gases outside, causing it to lock out for your safety.
Your boiler has detected that the internal exhaust fan is still running or stuck when it should be completely stopped.
Your boiler has detected an issue with either the gas supply or the blocked removal of exhaust gases, so it has safely stopped working.
Your boiler has detected an internal fault with its main electronic brain, which stops the burner from operating safely.
Your boiler has detected an internal communication error with its main control brain, meaning it cannot operate safely and has shut down.
Your boiler has detected an internal computer error and needs to be restarted.
BoilerFaultCodes