Set Appliance State:

Mains Power Off
CH Demand
Mode Selector Switch to CH position
Gas On
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Observation:

Run CH for 5 to 10 minutes and monitor the system pressure on the gauge.
The system pressure should remain stable at approximately 1.5 to 2 bar.