72 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an electrical issue with its internal pump, meaning it cannot circulate water effectively to provide your home with heat or hot water.
Your boiler has detected an issue with your solar water heating system, meaning it cannot currently communicate with or properly integrate the solar-heated water into your home's system.
Your boiler has detected that the internal air circulation fan is not starting or running correctly, so it has turned itself off to stay safe.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler is trying to start but the flame is failing to light or stay on, so it has stopped for your safety.
Your boiler has detected an internal error where it thinks a flame is present when it actually isn't, causing the system to shut down for safety.
Your boiler has stopped working because the flame has unexpectedly gone out while it was trying to heat your home.
Your boiler has been intentionally switched off by an external device, such as a smart controller, a timer, or a safety sensor, which is preventing it from firing up.
Your boiler's computer is having trouble communicating with its internal components, meaning it has safely shut itself down to prevent any further issues.
Your boiler has detected an electrical issue with the internal component that controls the gas supply, meaning it cannot safely start up to provide heating or hot water.
Your boiler's internal computer is having a communication error because its software does not match the hardware components currently installed.
Your boiler has detected an internal communication error between its main control components, causing it to stop operating until the issue is resolved.
Your boiler's main computer is having trouble communicating, which has caused the system to shut down for safety.
Your boiler's main control unit is having trouble communicating with its internal electrical components, which has caused the system to shut down for safety.
Your boiler has detected an internal communication or software issue with its main control board, meaning it has safely shut itself down to prevent potential damage.
Your boiler's main computer has encountered an internal error and cannot communicate with the rest of the system to operate safely.
Your boiler's internal computer is experiencing a communication error, meaning it has safely shut itself down to prevent potential damage.
Your boiler's main computer brain is experiencing a technical communication error, meaning it cannot safely operate your heating or hot water.
Your boiler's internal computer is experiencing a communication error, meaning it has safely shut down to prevent incorrect operation.
Your boiler's internal computer is experiencing a communication error and has shut down to prevent incorrect operation.
Your boiler's main computer is having trouble communicating, which has caused the system to shut down to prevent further issues.
Your boiler's main computer has detected a serious internal communication error and has shut itself down to prevent damage.
Your boiler's main computer has encountered a serious internal error and can no longer safely operate your heating or hot water system.
Your boiler's internal computer has encountered a serious error and is unable to communicate with its own systems, causing it to shut down for safety.
Your boiler's internal computer has detected a serious electronic error and has stopped working to protect the system.
Your boiler's internal computer is experiencing a communication error, causing the system to shut down for safety.
Your boiler's main computer is having trouble communicating, which has caused it to shut down to prevent potential damage.
Your boiler's internal computer is experiencing a communication error, meaning it has safely shut down to prevent damage.
Your boiler's main control computer is experiencing a communication error, causing it to shut down to prevent incorrect operation.
Your boiler's main computer is having trouble communicating, which has caused it to shut down for safety reasons.
Your boiler has detected an issue with the burner flame during operation and has safely shut itself down to prevent any risk.
Your boiler has detected a problem with the internal air or exhaust flow and has safely shut itself down to prevent it from running incorrectly.
Your boiler has detected that the water pump is struggling to move water around your heating system, likely because it is jammed or there is trapped air in the pipes.
Your boiler has detected that a flame is still present even though it has commanded the gas to turn off, which indicates a potential safety issue with the shut-off system.
Your boiler's internal computer has encountered a serious communication error and cannot safely manage the heating or hot water system.
Your boiler's computer is having trouble communicating with the internal parts, causing the system to stop working to ensure safety.
Your boiler's internal computer has detected a serious communication or hardware error that prevents it from operating safely.
Your boiler has detected an internal communication error and has safely shut itself down to prevent operation while it is uncertain about its internal control status.
Your boiler has lost the connection to the temperature sensor in your hot water cylinder, which means it cannot reliably detect when your water needs heating.
Your boiler is struggling to accurately monitor the temperature of the water returning to it, which prevents it from heating your home safely.
Your boiler has detected an internal electronic error that is preventing it from operating safely.
The boiler's internal computer is experiencing a communication error and cannot operate correctly, which has caused your heating and hot water to shut down.
Your boiler is struggling to clear exhaust gases properly, likely because the external vent is blocked, disconnected, or damaged.
Your boiler's electronic control system is experiencing an internal communication error, which means it cannot safely operate your heating or hot water.
Your boiler's main control unit is experiencing a communication error, meaning it can no longer safely operate your heating or hot water system.
Your boiler's internal computer is struggling to communicate with its electrical components, preventing it from starting safely.
Your boiler has stopped working because it cannot confirm that the internal flame is burning correctly, so it has shut down for your safety.
Your boiler's internal computer has detected a significant electrical communication error that is preventing the system from operating safely.
Your boiler's internal computer has detected a serious electronic communication error, meaning it has safely shut itself down to prevent further damage.
Your boiler's internal electronic control system has encountered a communication error and is unable to operate safely.
Your boiler's internal computer is struggling to communicate properly with its components, causing the system to stop working as a safety precaution.
Your boiler's main control unit has detected an electrical communication failure, meaning the system cannot safely operate your heating or hot water.
Your boiler's computer has encountered a serious internal error and has shut itself down to prevent damage, meaning you currently have no heating or hot water.
Your boiler's main computer has encountered a serious internal error and can no longer safely control the heating system.
Your boiler has detected an internal electronic error within its main control system, meaning it has safely shut itself down and cannot operate until the fault is cleared.
Your boiler's internal computer has identified an incorrect configuration card, which prevents it from operating safely.
Your boiler is failing to ignite because it cannot maintain a stable flame at the lowest power setting.
Your boiler is attempting to start but is failing to detect a flame, meaning it cannot produce heat or hot water.
Your boiler is trying to ignite but cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is struggling to keep its flame lit and has shut itself down as a safety precaution.
Your boiler has detected an internal error while checking the flame sensor, meaning it cannot confirm that the burner is operating safely and has stopped working to prevent a hazard.
Your boiler's electronic control system is confused because it is set up in a way that doesn't match the physical equipment installed in your home.
Your boiler's internal computer has detected a significant electrical communication error that is preventing it from operating safely.
Your boiler has detected that the internal exhaust fan is not spinning or responding, which prevents the unit from starting safely.
Your boiler has stopped working because it cannot confirm that the internal fan, which clears exhaust gases, is running correctly.
Your boiler has detected invalid temperature readings, meaning it cannot safely determine how much to heat your water and has switched itself off to prevent potential damage.
Your boiler has detected that the water inside the system is getting much hotter than it is supposed to be, so it has stopped working to prevent any potential damage.
Your boiler has shut down because it cannot circulate water through your radiators, likely due to low system pressure or a blockage.
Your boiler has detected that the water inside is heating up far too quickly, which usually suggests a restricted flow preventing heat from moving away from the burner correctly.
Your boiler has detected that it is heating up far too quickly, likely because water is not flowing through the system as it should.
Your boiler is struggling because the electricity supply coming into your home is dipping below the level required to keep the system running reliably.
Your boiler is preventing itself from overheating because the water inside is heating up much faster than it can be moved around your home.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes