Norcold refrigerator question

We have a 12 cu ft Norcold refrig. on a slide(1200LR), and recently had a new condenser installed because the refrig wasn't cooling below 50 degrees. Our refrig has 9 settings and I have to keep adjusting it depending on the outside temperatures. If it is going to be cold at night I have to set it on 5 or 6 so the food won't freeze. If it is hot (75 -80+ degrees) during the day, I have to set it on 9 and then re refrig will maintain a temp of 42-46. Since the refrig is on a slide, it is not vented out the top, but out the side. Has anyone else experienced this problem?

Your help is greatly appreciated.