The prototype was successful with one major lesson learned: the water meter for recording the total amount of collected condensate should be installed either in the vertical section of pipe above the pump, or in a U-trap in the horizontal run, because, otherwise, the pipe is never totally full of water, and an impeller-type meter could misread the flow volume.
The dimensions of the U-trap in the existing condensate drain pipe between the AHU and the floor drain should be maintained when connecting the drain pipe to the external collection pan.