What is Load Calculation (Manual J)?
Manual J is the industry-standard engineering method for calculating exactly how much heating and cooling a specific home needs, room by room — factoring square footage, insulation, window area and orientation, ceiling height, and air leakage. It's how a system gets sized correctly instead of guessed at.
Why it matters in Arizona
Desert homes punish sizing mistakes: an oversized AC short-cycles, dies younger, and controls humidity poorly during monsoon weeks, while an undersized one runs flat-out and never catches up in July. If a contractor quotes tonnage without measuring anything, that's a guess, not a size.
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