57 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost communication with a sensor that monitors the water temperature for your third heating zone, which will prevent that specific area from heating correctly.
Your boiler has lost communication with the solar panel sensor on your roof, meaning it can no longer monitor the solar heating system properly.
Your boiler is having trouble communicating with the solar heating part of your hot water system, meaning your water might not be heating as efficiently as it should.
Your solar heating system is struggling to move fluid correctly, which could be due to a blockage, air in the pipes, or a safety sensor cutting in to prevent overheating.
Your boiler is having trouble communicating with the solar heating components, meaning your solar panels won't be helping to heat your water right now.
Your boiler has lost its connection to the external weather sensor, meaning it may not know how hard it needs to work to heat your home accurately.
Your boiler has lost its connection to the outside weather sensor, which helps it decide how hard it needs to work to heat your home.
Your boiler has lost its connection to the wireless sensor that tells it how cold it is outside.
Your boiler has stopped working because it cannot correctly measure the temperature of the water flowing into your heating system.
Your boiler has lost connection with its internal temperature sensor, meaning it cannot monitor water heat and has shut down as a safety precaution.
Your boiler has detected a fault with its internal thermometer and has stopped the burner from firing to prevent overheating and damage.
Your boiler has stopped working because it cannot accurately measure the temperature of the water inside the unit.
Your boiler has detected a sensor fault in your second heating area, which means it cannot accurately measure the temperature of the water flowing to those radiators.
A sensor that monitors the water temperature in one of your heating zones has developed a fault, which may prevent that part of your home from warming up correctly.
Your boiler has lost connection with a temperature sensor for your underfloor heating or second heating zone, meaning that specific area may not warm up correctly.
Your boiler has lost its connection to the hot water storage tank sensor, which means it cannot heat your water for taps and showers.
Your boiler has detected a faulty internal sensor, which means it cannot tell the temperature of your water and has stopped providing hot water as a result.
Your boiler has detected an electrical fault in the sensor that monitors the temperature of the water flowing through the system, causing the unit to stop operating as a safety precaution.
Your boiler has lost connection with the sensor that monitors your hot water tank, meaning the system cannot heat your water for taps and showers.
Your boiler has lost its connection to the hot water temperature sensor, meaning it cannot heat your water for taps and showers.
Your solar heating system has detected a fault with the temperature sensor on your roof, meaning it cannot currently heat your water using solar energy.
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 has detected that the water pressure is too low for it to operate safely, meaning your heating and hot water will likely be limited.
Your boiler has detected that a temperature probe monitoring your exhaust gases is not sitting correctly in its intended spot.
Your boiler has detected that the water pressure inside your central heating system has become too high, which can put unnecessary strain on the internal components.
Your boiler's electronic control panel is experiencing a communication error or internal failure, meaning it cannot process settings or operate your heating system correctly.
Your boiler is struggling to push water through the system, likely because there is trapped air or a blockage preventing proper flow.
Your boiler is having trouble 'talking' to your room thermostat, which means it may not know when to turn the heating on or off.
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 overheating.
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's internal computer has detected an unexpected system error, causing it to shut down for safety reasons.
Your boiler's computer is struggling to read its internal identification chip, which means it cannot safely start up or regulate your heating.
Your boiler has detected that a sensor measuring the temperature of the exhaust fumes has stopped working, so it has shut down as a precaution to ensure it remains safe to operate.
Your boiler has lost the digital connection to an external accessory, such as a solar thermal unit or an additional heating control, preventing the system from coordinating properly.
Your boiler is struggling to talk to the part of the system that manages your solar-heated water, which means the solar panel integration isn't currently working.
Your boiler is having trouble 'talking' to an accessory unit, which is likely preventing it from managing your heating or hot water correctly.
Your boiler has lost its connection with your external thermostat or smart controller, meaning it doesn't know when to turn your heating on or off.
Your boiler is having trouble communicating with its internal water pump, which means it cannot circulate heat effectively around your home.
Your boiler is struggling to communicate with an external accessory or control unit, which may cause your heating or hot water to function inconsistently.
Your boiler has detected an issue with an external device or sensor connected to it, such as a solar thermal system or an external controller, which is currently preventing normal operation.
Your boiler has detected an external signal or safety switch connected to it that is currently reporting an error, which is preventing the system from operating normally.
Your boiler has detected an issue with how it manages its internal flame, causing it to shut down for safety reasons.
Your boiler has detected that it is overheating because it cannot effectively move the heat away from its internal components, causing it to shut down for safety.
Your boiler has detected a problem with its internal electrical power supply, which is preventing it from operating correctly.
Your boiler has detected an internal electronic malfunction and has shut down to protect itself, meaning you currently have no heating or hot water.
Your boiler has stopped working because the water pressure inside your heating system has dropped below the required level.
Your boiler is failing to detect a steady flame during its internal setup process, which is preventing it from starting up correctly.
Your boiler is struggling to detect the flame correctly, so it has safely shut itself down to prevent any issues.
Your boiler has detected an internal electronic error that is preventing it from operating correctly.
Your boiler has detected that the exhaust gases leaving your home are becoming dangerously hot and has shut itself down to prevent overheating.
Your boiler has detected that it is overheating and has automatically shut itself down to prevent damage or dangerous pressure buildup.
Your boiler has detected a flame signal when it shouldn't be there, which means it cannot safely start up as it believes the fire is already lit.
Your boiler is trying to start but cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is currently unable to read the water pressure inside the system because the sensor responsible for this measurement is not communicating properly.
Your boiler has detected an issue with the internal gas control valve, meaning it is not closing as quickly as it should when the burner turns off.
Your boiler is failing to start because the internal air circulation fan is not spinning fast enough to safely begin the combustion process.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes