What size central air-conditioning compressor do I need?
On One Hand: Do Your HomeworkThe method used by good contractors to determine the proper size of an air-conditioning compressor is the design load calculation. This method takes into consideration factors such as building insulation; air leaks; seals and insulation on ducts; size, type, number and direction of windows; overhang and landscape shading; and size, layout and orientation of the building.On the Other: Don’t Cut CornersSome contractors use the rule-of-thumb method, or guidelines based solely on building area, to determine compressor size. According to the U.S. Department of Energy, rules of thumb can overestimate the size [of compressor] needed” and are not always reliable.Bottom LineConsumerSearch.com advises, “Make sure your contractor does a Manual J cooling-load calculation …
