Set Appliance State:

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

Observation:

Allow CH to operate and reach a reasonable temperature (approx 60°C).
Remove CH demand.
Does the pump continue to run for approximately 30 seconds?
Note:
You may wish to turn off some radiators to reduce time taken for system to heat up.