How hard is it to do the "Manual J" A/C tonnage calculation for a residential detached home?
(Case in point: a 1966 brick ranch home in Denver Metro; 1400 sq ft main level, 1200 sq ft basement.)
What is the procedure to follow? Download the Manual J spec and follow the instructions? Or is there some kind of software or Excel spreadsheet that will make the calc easier?
I know I'm supposed to insist that the HVAC contractor use the Manual J method, but how do I verify that that they indeed did it correctly, took all the factors into account, did not cut corners in the formulas, etc?
cheers