This was my first one. Questions:
The fresh air intake was not sealed at the unit as well as sloping away from the unit before it went up through the roof, problem?
Exhaust vent has “trap” installed to catch condesate, 2 lines, small one drains to a little plastic tub, big one loops around and has water in the line but doesn’t go anywhere.
I think the answers are obvious, but take a look and see if you notice anything else.