Why does my AC unit make the floor in the next room cold?
Do you like spiders and field mice?  You do? Great, you're gonna love this. 

There are some pipes running underneath the trailer, between the air conditioning unit (ironically called the condenser) outside, and the air handler or mini-split inside your trailer (ironically called the evaporator even though it condenses water).  

Those pipes are supposed to be wrapped with insulation.  I'm betting they're not anymore, as it has degraded or a mentally ill rodent made a meal of it. (clearly not the rat from Ratatouille.)   You would need to go on down there and have a looksy, and replace it with insulation from the building supply if so.