Set Appliance State:

Mains Power Off
DHW Demand
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Mains reset switch On.
Does the pump run with the HW demand?
Do not take noise or vibration as pump running.
Note:
If removing the pump screw please contain any water spillage safely to prevent damage to the electrics.