75 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a minor fluctuation in the water circulation system, but it is still operating safely and does not require immediate intervention.
Your boiler has detected an internal communication or unexpected electronic fault that is preventing it from operating correctly.
Your boiler is having trouble communicating with your solar water heating system, which may prevent the solar panels from boosting your hot water.
Your boiler has shut down because the water inside its internal loop has become hotter than the system is programmed to allow.
Your boiler has detected that the internal fan responsible for clearing exhaust gases has failed to start correctly, so it has automatically shut down to keep your home safe.
Your boiler has stopped working because it cannot confirm that the internal fan is blowing air correctly to safely clear exhaust gases.
Your boiler has detected that it has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler is trying to start, but it cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is confused because it senses an internal signal that makes it think the flame is burning even when it is not, causing it to shut down for safety.
Your boiler is struggling to stay lit and has cut itself off as a safety precaution because it cannot maintain a stable flame.
Your boiler has been instructed to turn off by an external device, such as a smart thermostat, weather sensor, or a specialized security system.
Your boiler's computer is having trouble recognising its own internal settings and components, which means it has safely shut itself down to prevent further issues.
Your boiler is struggling to communicate with the part that controls the gas supply, meaning it cannot ignite to provide heat or hot water.
Your boiler's internal computer system is having a communication error because it cannot recognise the current configuration of the internal electrical parts.
Your boiler has detected an internal communication error and has safely shut itself down to prevent potential damage.
Your boiler's main computer control panel has encountered an internal error and cannot communicate with the rest of the unit to heat your home.
Your boiler has detected an issue with its internal electronic control system that prevents it from operating safely.
Your boiler's internal computer has encountered a critical communication error and needs to be reset or inspected by a professional.
Your boiler's main computer brain is experiencing a technical communication error, meaning it has safely shut down to prevent incorrect operation.
The internal computer board of your boiler is experiencing a communication or processing error, which has caused the system to shut down for safety.
Your boiler's internal computer is experiencing a communication error or software glitch that is preventing it from operating correctly.
Your boiler's main computer brain is experiencing a general error and cannot communicate properly to start the system.
Your boiler's main computer brain is experiencing a internal communication error, which has caused it to stop working for your safety.
Your boiler's main computer is experiencing a software or communication error and has safely shut itself down to prevent potential damage.
Your boiler's main control computer is experiencing an internal error and cannot communicate with the rest of the unit, meaning it has shut down for safety.
Your boiler's internal computer is experiencing a memory error, which means it cannot safely control its own operation and has shut down to protect itself.
Your boiler's main control computer is experiencing a communication error, meaning it has safely shut down to prevent incorrect operation.
Your boiler's main computer system has encountered an internal error and needs a reset to try and regain control.
Your boiler has detected an internal communication error with its main control system, meaning it cannot process the signals needed 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 computer has encountered a memory or communication error and is unable to follow its normal startup routine.
Your boiler is struggling because it is producing more heat than your home is currently ready to absorb, which usually happens when the internal flow of water is blocked or restricted.
Your boiler has detected that the flame inside is not staying lit as it should, so it has turned itself off to stay safe.
Your boiler has detected that the internal components responsible for burning fuel and venting gases are not communicating properly, so it has safely shut itself down to prevent unsafe operation.
Your boiler is not detecting enough water flow or pressure to push warmth into your radiators and taps.
Your boiler has detected that it is still sensing a flame even though it has tried to shut off the gas supply, which could indicate a safety issue with internal components.
Your boiler has detected an electrical fault in a temperature sensor, which is preventing it from safely heating your home or water.
Your boiler's internal computer has lost its 'identity' because the small data chip that tells it how to operate correctly is either faulty or not plugged in properly.
Your boiler's computer is having trouble recognising its internal configuration or has suffered a hardware failure, meaning it cannot operate safely.
Your boiler's main control computer is experiencing an internal error and cannot communicate properly, which means it has shut down as a safety precaution.
Your boiler has detected that a small valve responsible for controlling the fuel supply is not closing properly, which means it cannot operate safely.
Your boiler has detected a failure within its internal electronic brain, meaning it has safely shut itself down to prevent any unsafe operation.
Your boiler is struggling to accurately measure the temperature of the water being heated for your taps and shower, so it has stopped heating it to prevent overheating.
Your boiler is struggling to accurately read how hot the water returning from your radiators is, which prevents it from heating your home properly.
Your boiler is currently unable to accurately read the water pressure inside the system because the sensor responsible for this signal has stopped working or has lost its connection.
Your boiler has detected an internal software or communication error that is preventing it from operating safely.
Your boiler's main computer control panel is experiencing a communication or processing error, preventing the system from operating safely.
Your boiler is struggling to breathe properly because its flue pipe, which vents gases outside, may be blocked or disconnected.
Your boiler's internal electronic brains have lost their connection, meaning the system cannot safely ignite to provide heating or hot water.
Your boiler's main control unit is experiencing a communication error, which has caused the system to shut down for safety reasons.
Your boiler's internal computer is struggling to communicate with its electrical parts, which has caused the system to shut down for safety.
Your boiler is struggling to detect the flame correctly and will stop working to keep your home safe.
Your boiler's internal computer is struggling to communicate with its electrical components, preventing it from starting up correctly.
Your boiler's internal computer is struggling to communicate with its electrical components, preventing it from starting up safely.
Your boiler's main control system is experiencing a communication error, which has caused the unit to shut down for safety reasons.
Your boiler's internal computer has detected a serious communication error between its electronic components, causing the system to stop working for safety reasons.
Your boiler's computer is experiencing a temporary software glitch and cannot communicate correctly with its internal systems.
Your boiler's internal computer is experiencing a critical processing error and has stopped functioning to protect itself from unpredictable operation.
Your boiler is struggling because it is not receiving the correct amount of electrical power, which is stopping it from operating normally.
Your boiler's computer is struggling to identify the specific configuration chip meant for your model, causing it to shut down for safety.
Your boiler is attempting to start but is failing to stay lit because it cannot detect a flame, which has caused it to shut down for safety.
Your boiler is trying to start but is failing to detect a flame, which means your heating and hot water have stopped working.
Your boiler is attempting to light but is failing to detect a flame, meaning it cannot produce heat or hot water.
Your boiler is repeatedly failing to keep its internal flame lit, so it has stopped working to keep your home safe.
Your boiler is having trouble confirming that the burner has lit safely, so it has stopped working to keep your home safe.
Your boiler's computer settings do not match the way your heating system has been physically installed, preventing it from functioning correctly.
Your boiler's internal computer has detected a general electrical fault, which means the system has safely shut down to prevent further damage.
Your boiler has stopped working because it cannot confirm that the internal fan, which is essential for safely clearing exhaust gases, is spinning correctly.
Your boiler has identified an issue with the internal air circulation system, which is preventing it from lighting safely.
Your boiler has detected data from its internal temperature sensors that falls outside the expected range, prompting it to shut down for safety.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has shut down because the water inside it is heating up much faster than it can be moved around your system.
Your boiler has detected that the water pressure in your heating system is dropping much faster than it should, which usually points to a leak somewhere in your radiators, pipes, or the boiler itself.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Your boiler is struggling because the electricity supply coming from your mains is weaker than required to operate safely.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes