BoilerFaultCodesYour boiler is currently trying to light the flame to provide hot 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: DHW mode: Ignition. The ignition for domestic hot water mode is activated.
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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A boiler cover plan would cover faults like S.13 — no call-out fees, no surprises.
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