Is cool air supposed to be blowing out of my condensate drain on my central ac unit where the evaporator coils are?.
I also feel air blowing out of the hole where the freon lines run into the evaporator housing.
Both of the above comments are describing the part of my ac that sits just down stream of my furnace.
I posed the same questions to the HVAC tech who serviced my AC a couple of weeks ago. My condensate line has a short vertical tube which discharges some cool air, and looking down through it, you can see the condesate draining through the horizontal part. He said this is by design. As for some air escaping around the coolant lines where they enter the coil, he applied some tape to get a better seal.
Any holes in the plenum (the box around the coil) should be sealed just as any air leaks in the ductwork. If there is a trap on the condensate line it shouldn't have any openings between the coil and the trap an open vent after the trap isn't a problem.