Set Appliance State:

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

Measurement:

CH temperature set to MAX
Allow the boiler to run on central heating, is the heating operating satisfactorily?
Monitor the pressure to check that it does not rise excessively as the system heats.
Note:
Syphon fill mode can be disabled if required to test the heating by entering the installer mode and accessing level 4 - A2.
(click here for information on how to do this)
Then changing the setting to 0 (Siphon Fill Off) this should only be done during a repair or maintenance visit and must be reset correctly afterwards to 1 (Siphon fill on at minimum).