On some roof airs, like the Coleman, you can tighten the four bolts. As the seal compresses, the spring tensioners on the bolts try to keep it from leaking.
If you have a Coleman, remove interior unit locate the four bolts. They are 9/16 inch socket size. Tighten them up.
If you plan on replacing seal you would need to provide make and model.
Yes, the units are not the lightest. I was able to roll mine onto heavy card board that was used to protect roof. It would be better with two people to lift unit straight up and over onto cardboard or some other protective material.
