BoilerFaultCodesYour boiler is currently preparing or delivering hot water, which is a normal operating status of the pre-heat function rather than a failure.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Check diagnostic code - Warmstart / DHW demand (turboMAX Plus only)
What causes this fault?
This status occurs when the boiler's internal pre-heat function, known as Warmstart, is active to ensure hot water is available quickly. It is triggered either by the boiler periodically heating its own internal store or when you turn on a hot water tap. This is part of the appliance's normal operation and indicates the system is working as intended to maintain comfort.
DIY fix possible
Check if the hot water tap is currently runningTurn off the 'Warmstart' comfort function using the dial if you do not want the boiler to fire periodically to keep water hotMonitor the display to see if it switches back to a heating or standby code once the demand ends
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