This is a great forum. I have learned so much that I am actually EXCITED to spend $30K on an heating and AC system!
Here is my situation. I have calculated my heating and cooling requirements using HVAC-Calc inputting very conservative values. The program spits out that I just need a 4 ton system for cooling. The local HVAC contrators who have NOT DONE a manual j calculation think I am crazy. "5 ton minimum" "I would add two 3 ton system" " 1 ton per 800 sqft" etc.
So I am I wrong to assume that a 4 ton system will work?
Here are additional details:
rancher w/ basement
r4 insulation on outside, r13 in walls
west side partially shaded
aluminium radiant barrier in ceiling under rafters (over 5,000 sqft of the stuff!!)
latest andersen windows, only two facing north, most facing west.