BoilerFaultCodesTechnical description
DHW flow rate: Hot water flow rate.
What causes this fault?
This code is triggered when the boiler's internal sensor detects water moving through the hot water pipes, even if you haven't turned on a tap. It often occurs due to a 'passing' tap that isn't fully shut off, a minor leak in the pipework, or a sensor that has become overly sensitive or faulty. Effectively, the boiler is simply notifying you that it is working to heat water because it believe there is a demand.
DIY fix possible
Check that all hot water taps in the property are fully closedInspect for any dripping taps or leaking shower headsMonitor the display to see if the code clears once water usage stops
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