Set Appliance State:

Mains Power Off
CH Demand
Locate pump position on system
Boiler on/off switch ON
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Does the pump run?
Note:
The pump is not an integral part of the appliance.
Do not take noise or vibration as evidence of pump running.