[JRTJH]

The Passport 3221BH is a 37' trailer. It comes "standard" with a 13,500 BTU air conditioner. The optional 15,000 BTU unit helps "a bit", but in reality, it will take at least two rooftop units to keep that trailer cool in 95F temperatures.

Some things you can do to help are:

Check the air return/supply box (in the filter area on the ceiling unit) to make sure the two are properly sealed. If cold air is being "sucked up the return" rather than being pushed through the ducting, it will reduce efficiency.

Check all the ceiling duct outlets to make sure they are properly sealed so no air is being lost into the ceiling cavity and all the cold air is being delivered into the rooms.

Check the "end run" beyond the last ducts to make sure they are sealed and not "allowing cold air to flow into the ceiling cavity.

Don't park in direct sunlight,

Keep the shades pulled to prevent hot sunlight from shining into the trailer.

Keep the awning extended to "shade" the side of the trailer from direct sunlight.

Start the air conditioner early in the day. It's easier to maintain the cool than to "overcome the hot"....

Consider a second rooftop unit if you have 50 amp shore power service. If you don't have 50 amps, then you're going to need to focus on the above suggestions since a second rooftop unit isn't an option without "very expensive electrical modifications"....