BoilerFaultCodesWhat the manual says
Manufacturer manualdomestic hot water demand
From this model's manual
Verified against the Glow Worm Flexicom Cx installation & service manual, page 45.
What causes this fault?
This code appears when the boiler’s internal sensors detect that a hot water tap or shower has been turned on somewhere in your home. It isn't a fault, but rather a status message confirming the boiler is successfully diverting energy to heat your water. If you see this when no taps are running, it could indicate a dripping tap or a minor internal sensor issue.
DIY fix possible
Check if any hot water taps are slightly open or drippingMonitor the display; the code should change once you turn off the hot waterNo action is required if hot water is currently being used
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