Coleman AC freezing up constantly?

Have you cleaned the evaporator coils? If they are dirty you will not get enough air through them and can/will ice up. Most of these units are sealed systems and freon cannot be added. Pull both outside and inside covers off. On roof you should be able to remove shroud covering evaporator fan and coils. I used my air compressor and back blow air through the coils, mind you this will also blow all the******back into RV. Once that is done I spray coil cleaner on both sides of coils, let sit and use a pump sprayer to rinse coils. Make sure you have towels on the floor. Not hard to do just messy. Clean out your condenser coils before closing everything back up. Hope this works. Good luck.