Set Appliance State:

NO demands
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Check the system pressure is 1 - 1.5bar (when cold).
Allow a small amount of water into the system via the filling loop and check that the gauge responds to the increase in pressure.
Check that there is no air in the boiler and system.
Note:
1. System pressure should be set between 1.0 and 1.5 bar.
2. It is also advisable to check the auto air vent on the pump hydroblock.