BoilerFaultCodesYour boiler is simply indicating that you have turned on a hot tap or shower and it is successfully heating the water for you.
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: Domestic hot water demand
What causes this fault?
This is not a fault, but a normal status message triggered when the boiler's internal flow switch or sensor detects water moving through the pipes. It signifies that the burner has successfully ignited to provide heat to your taps or shower. Once you turn the hot water off, this code will disappear and return to its standby state.
DIY fix possible
No action required; this is a normal status code, not a fault.The number 6 will disappear once you turn off the hot tap.
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A boiler cover plan would cover faults like 6 — no call-out fees, no surprises.
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