19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a false flame signal, meaning it thinks a fire is burning inside when it shouldn't be.
Your boiler has detected an electrical short circuit in its low-voltage control system, which causes it to shut down for safety.
Your boiler is trying to start up, but it is failing to ignite or stay lit after a couple of attempts.
Your boiler has experienced a power drop while attempting to lock out for a safety fault.
Your boiler is not detecting proper airflow or exhaust movement, which temporarily stops it from running safely.
Your boiler has detected an internal memory error within its main control unit, causing it to temporarily lock out for safety.
Your boiler has stopped working because an internal electrical fuse has blown, cutting power to essential components.
Your boiler has temporarily stopped working because the water inside it has become too hot.
Your boiler has detected that the flow and return water pipes or their temperature sensors may have been installed the wrong way around, or water isn't flowing correctly.
Your boiler has detected that the temperature of the water inside it is rising much faster than normal, which usually indicates poor water flow.
Your boiler has stopped working because the internal fan that safely removes combustion gases is not spinning.
Your boiler's internal fan is continuing to run constantly even when the heating or hot water is turned off.
Your boiler has temporarily stopped working because the water temperature getting too hot compared to the water returning, usually caused by a blockage in water flow.
Your boiler has temporarily stopped working because it has detected a short circuit in the main temperature sensor that measures how hot the water is.
Your boiler has temporarily stopped working because it has detected a faulty signal from one of its internal temperature sensors.
Your boiler has temporarily stopped working because it cannot properly read the water temperature due to a faulty or disconnected sensor.
Your boiler has detected an issue with a temperature sensor that measures the water returning to the system, causing it to temporarily pause heating to protect itself.
Your boiler's internal memory settings have gone out of the correct operating range, causing it to lock out for safety.
Your boiler has detected an issue with the air pressure switch not opening properly, which temporarily stops the appliance from firing up safely.
BoilerFaultCodes