37 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a flame inside when it shouldn't be burning, so it has safely shut down to prevent any risk.
Your boiler's main control computer has encountered an internal error and can no longer safely manage the heating system.
Your boiler has detected an electrical wiring short circuit, causing it to safely shut down to prevent further damage.
Your boiler's main control computer has encountered a serious internal error and has shut down to prevent further damage.
Your boiler is trying to start up, but it cannot detect a flame to keep the burner lit, so it has safely shut down to stop unburnt gas from building up.
Your boiler's main brain has detected a critical internal error, which means it has safely shut itself down to prevent further damage.
Your boiler's main electronic control unit has encountered an internal communication error and has safely stopped working.
Your boiler has detected a serious internal fault that has permanently shut it down for safety reasons and it requires a professional to reset it.
Your boiler has temporarily stopped working because it cannot safely detect the correct airflow needed for combustion.
Your boiler has detected an internal computer error that is preventing it from starting up safely.
Your boiler has detected an internal computer error that is preventing it from starting up safely.
Your boiler's main control unit has detected a critical internal error and has shut down to prevent further damage.
Your boiler has detected a problem with the internal air flow system, which prevents it from igniting safely.
Your boiler has automatically shut down because the water inside has become dangerously hot.
Your boiler's main computer brain has detected an internal error and has shut down for safety, meaning you currently have no heating or hot water.
Your boiler's main control unit has detected a serious internal system error and has shut down for your safety.
Your boiler has stopped working because it cannot detect enough water pressure or has identified an issue with the exhaust flue system.
Your boiler's main computer brain has encountered a internal error and needs to be reset or inspected by a professional.
Your boiler has detected a critical internal computer error and has shut itself down as a safety precaution.
Your boiler's internal computer has encountered a critical error, meaning it has safely shut itself down to prevent further issues.
Your boiler's main control computer has detected a serious internal processing error and has shut down to prevent unsafe operation.
Your boiler's main control computer has developed an internal error and can no longer safely manage the heating system.
Your boiler has temporarily stopped working because the water inside it has become too hot.
Your boiler has temporarily stopped because the water returning from your radiators is getting too hot, which helps protect the system from overheating.
Your boiler's temperature sensors have been incorrectly wired or swapped, causing the system to misread the water flow and preventing it from operating safely.
Your boiler is getting too hot too quickly, usually because water isn't circulating through the system properly.
Your boiler is failing to ignite because it is not receiving enough gas to run safely.
Your boiler has stopped working because the internal fan, which clears exhaust gases, is failing to spin or report its status correctly.
Your boiler has detected that the fan, which is responsible for safely venting fumes, is spinning but not reporting its speed correctly to the control system.
Your boiler has detected an issue with the electrical power supply to the unit while it was running.
Your boiler has temporarily stopped working because it has detected a faulty reading from one of its internal temperature sensors.
Your boiler has temporarily stopped working because a temperature sensor is giving an incorrect reading.
Your boiler has stopped working because it has lost the signal from its primary temperature sensor, which measures how hot the water is getting.
Your boiler has detected an issue with a temperature sensor, causing it to temporarily stop working for your safety.
Your boiler has detected an internal electronic error and has safely shut down to prevent further issues.
Your boiler has detected an internal electronic error and has safely shut down to prevent further issues.
Your boiler has detected an internal electronic error and has safely shut down to prevent further issues.
BoilerFaultCodes