tshogan

Thanks Windbreaker, I will give it a try.  It looks like trial and error on the adjustment.  Tipper, yes a rear roof ac was added and two front roof vents.  We are not the original owner.  We just bought this a week ago and are in the process of learning what we have.  I lucked up and found this wonderful message board with lots of help a few weeks before I bought the trailmanor.  Its a 1990 Trailmanor 28.  I hope the instructions will work for one that old.  I plan on joining trailblazer soon and hopefully visiting the factory.  
tshogan