It sounds like my old AC unit I had in my 2003 Prowler. You set the fan speed and that does run all the time. For the temp, if you crank it to the coldest setting, it'll run forever I'd think..
If you get to the temp you want, you should be able to turn the temp knob to a warmer setting and then hear the compressor turn off.. The fan will still run.
Then as the rig warms up again, you should hear the compressor kick on again and start blowing cold air.
My new Rockwood trailer does have a wall mounted thermostat for both the heat and AC. For the AC, it does have the option to turn off the fan when the desired temp is reached. There is no fan/temp knobs on the AC unit on the Rockwood.
Good luck! Mitch
2013 F150 XLT 4x4 SuperCab Max Tow Egoboost 3.73 gears #7700 GVWR #1920 payload. 2019 Rockwood Mini Lite 2511S.