BoilerFaultCodesWhat the manual says
Manufacturer manualdomestic hot water demand
From this model's manual
Verified against the Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
What causes this fault?
This code appears when the boiler's internal flow sensor detects that water is moving through the hot water pipes. It triggers the burner to ignite so that it can provide an immediate supply of heat to your taps or shower. This is a normal operational message rather than a mechanical failure.
DIY fix possible
Check if any hot water taps have been left running slightlyEnsure your shower is fully turned offNo action is required as this is a normal status message, not a fault
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