BoilerFaultCodesYour boiler is providing a status update to show it is currently heating up the water for your taps.
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: Burner start up in hot water mode
What causes this fault?
This code appears when the boiler detects a demand for hot water and begins the ignition sequence to heat it. It is not actually a fault, but a status message indicating that the internal burner is firing up to provide water for your taps or shower. Once the water reaches the required temperature, the code will usually change or disappear.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like D.83 — no call-out fees, no surprises.
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