Ok, HVAC professionals if I'm not out of line with my question here goes. My house size is 2300 sq.ft., two levels, the attic has 12 inches of cellulose, the walls are filled to R-11, the windows are double pane, LowE krypton filled with with a .28 U- factor and the entry doors are weatherstripped. The blower door test says the house has a .2 air changes per hour rating and the house is pretty tight. It also stated I need 55cfm in the house. Now, I have a Sears AC 2.5 or 3 ton unit that was installed in 1986 or 1987 and a Carrier 58SSB095-BC gas furnace that was installed in 1988. I would like to change both units out in order to receive better comfort and more efficency in my home. Ok , now for the hard part, my contractor say's his company does not normally do a load calculation on change outs and that should have been done when the original system was installed. Also if the current sizes worked fine cooling and heating the house stay with what I got except for modernizing the equipment. Based on his inspection of the property he thought a 3 ton 13 SEER unit and a 80% 2 stage VS system would work just fine based on his eyeballing the place. I realize most of you guys say "go with what your contractor recommends" but should that rule work in this situtation. The price of the equipment and install is not the problem, but am I getting the right size of equipment for the house. There are four people in the house and we like like it warm, not hot, in winter and cool in summer. We are in the mid-Atlantic section of the country. Sometimes cold and always hot in summer. Thank you for your input and have a cold one on me.