BoilerFaultCodesWhat the manual says
Manufacturer manualDHW mode: Ignition. The ignition 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 isn't actually a fault, but a status message indicating that you have turned on a hot tap and the boiler is starting its ignition process. It occurs because the internal sensor has detected water flow and is now sparking the burner to heat that water for your shower or sink. If the code stays on screen without the water getting hot, it may suggest an issue with the gas supply or the ignition electrodes.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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