I think your tech didnít want to try to diagnose the issue. Is he/she the only tech at the dealership? You donít have to go to a Keystone dealer, any authorized repair facility that deals with your BRAND of AC can look at it under warranty.
2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.