Receiently had a new Alpine 150 installed in our home.

Had several problems and realized my plumber/installer had on idea on how to size a boiler or set it up proberly.
After many hours of reading the manual and boiler operation observation, and posting questions I am somewhat up to speed and have a handle on whats going on.
On e question if I may: I am trying to determine the actual D/T on my system. The system was plumbed with P/S loops. In reading the return temp on the screen am I not reading both the zone return water temp mixed with the boiler pump water also? If so then would this not would give a incorrect higher than actual zone return water temp?