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.
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