Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
CH Demand
Slacken water pump manual restart nut and take precautions to ensure any water released is safely contained
Gas On; Pilot On
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

After approximately 6 seconds from main burner ignition
verify that the pump is running.
Note:
Do not take noise or vibration as an indication that the pump is running.