Well I finally had a chance to climb up there a find a model number for the evaporator (from my old fridge days, I think that is a good name for it).
I have attached the appropriate pics. of the unit and the manual. The PDF was too large so I had to screen capture the necessary pages.
My interpretation is that both condensate drains are draining the same area. Would you concur?
If so, should I just add another short length from the plugged line to the pan below?
But that drain from the pan is useless. It has virtually no pitch across about a 20 foot run. It is just laying on a joist for the run then goes into a wall.
Maybe I should replace it with a line from the plugged outlet (which is 3 or 4 feet above the joists) with a pitch of about 3 or 4 feet across the 20 feet to where the far end of the pan drain line goes into a wall.
Or just rely on the switch on the pan. I tested it and it seemed to work.
Also, I was hoping to get some information about the recommended temperature drop but, no luck