BoilerFaultCodesWhat the manual says
Manufacturer manualDHW mode: Burner on. The burner for domestic hot water mode is activated.
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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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