The dash air on any motorhome does not cool quite as well as a car because of the large volume of air that it has to cool and the very high heat load that you can get from the sun coming in that huge windshield. Since you have about the same size compressor as a car and it usually is turning slower (depending on pulley sizes) there is not enough capacity to cool the whole cab area like a car can with the smaller area.
This being said, you should feel cold air at the duct outlet (usually a 40 deg. or so drop dependant on engine RPM).
As for a place to have it serviced, the air conditioner was installed by Beaver and Cat has no connection with the unit and most Cat dealers will not work on it. Beaver Coach Sales would be a good choice if they service air conditioners (not all RV service centers do) (call first).
I would give the unit a little time to see how it performs, it may be OK or it may need a partial recharge as all R134A refrigerant systems will have a slight leak over time.
Gerald
