Yep, Florida here. About 15 miles southeast of Tampa, as the crow flies. The insulation values (according to what the contractor wrote down) is R-30 in the ceilings and R-16.45 in the exterior block walls. You said something about the design temps are probably around mid 90's and 98 most likely exceeds the design temps of the system." I guess that would explain why this unit runs all the time in the summer. Geeze....everyone knows Florida freaking bakes down here....why the h*** would someone put in a unit that is not designed for the heat?? But after some of the things I saw and dealt with during construction, I believe it! I will look into tint and have someone check the insulation in the roof.
I noticed today in my son's room that it gets pretty warm in there even though the temp at the register says 61F. His room is on the southern side and is the farthest from the Trane. His sister's room is on the northern side of the house about 12' down the short hall and her room stays comfortable. The tstat is right in the middle between their rooms. My room is at the other end of the house right between the attic unit and the OD unit and it is always chilly in there. Maybe there isn't enough insulation at the far end over my son's room?