BoilerFaultCodesYour boiler is currently going through the normal steps to light the flame and start heating your home.
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: Ignition sequence
What causes this fault?
This is actually a status code rather than a fault, occurring every time your boiler prepares to provide heating or hot water. It indicates that the system is safely working through its internal checks to spark the burner and establish a flame. If the boiler stays stuck on this code without firing up, it usually suggests a temporary delay in the ignition process.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like S.23 — no call-out fees, no surprises.
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