Set Appliance State:

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

Observation:

Is the system pressure correctly set between 1
and 1.5 bar and the boiler and system free from air ?
Note.
If you suspect that the appliance has air in it, you can activate the de-aeration process by holding the RESET button in for 5 seconds. The boiler will run in this mode for approximately 5 minutes before restarting.