Set Appliance State:

CH Demand
Isolate Mains Power to appliance as per TOPs P4
Insert a link between the mains connector and the pump live at the main terminal block
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Does the pump now run?
If the pump has started to run does the appliance now operate?