Technical description
Fault occurs; requires reset (Turn On/Off switch to 0, wait five seconds, then to I).
What causes this fault?
This fault happens when the boiler tries to light the flame but fails to detect one after several attempts. It is usually caused by a temporary interruption in the gas supply or a worn-out component that struggles to create the initial spark. To keep you safe, the system shuts down completely until it is manually told that it is okay to try again.
This issue is more frequent during the first cold snap of winter when older components are under sudden strain after being idle over the summer.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.