BoilerFaultCodesYour boiler is simply working as intended by heating up the water for your taps or shower.
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: Boiler is supplying domestic hot water.
What causes this fault?
This isn't actually a fault, but a status message indicating that a hot water tap or shower has been turned on. The boiler has detected water flowing through the system and is firing the burner to provide instant heat to your taps.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 4 — no call-out fees, no surprises.
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Glow-worm Energysaver Combi 2 80 100 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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