Your boiler is currently trying to light the flame to start provide heating or hot water, and this is a normal status message rather than a permanent error.

Ignition sequence

What causes this fault?

This code appears when the boiler's control system sends a signal to generate a spark and open the gas valve simultaneously. It is a natural part of the start-up process where the appliance attempts to establish a flame to satisfy a demand for heat. If the boiler stays on this code without firing, it usually means there is a temporary struggle to sense the flame or a delay in gas reaching the burner.