BoilerFaultCodesYour boiler is simply indicating that it is currently firing up to provide hot water to 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: DHW mode: Burner on. The burner for domestic hot water mode is activated.
What causes this fault?
This is not actually a fault, but a status message that occurs when the boiler detects a demand for hot water. When you turn on a tap or shower, the internal flow sensor triggers the burner to ignite so it can heat the water passing through the heat exchanger. Once the tap is turned off, this code will naturally disappear as the boiler finishes its cycle.
DIY fix possible
No action requiredMonitor the display to ensure the code changes to S.0 or S.4 once you turn off your hot water tap
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A boiler cover plan would cover faults like S.24 — no call-out fees, no surprises.
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