Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Unclip diverter valve and place in a position where
the diverter spindle can be easily observed
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

During boiler the two minute self check diverter should move between the fully retracted and fully extended positions several times.
Observe for at least 1 minute to determine whether diverter is moving correctly.