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BTU Myths That Waste Money
Five common BTU assumptions that lead to oversizing, uncomfortable rooms, and higher energy bills.
Myth 1: 500 square feet always needs 12,000 BTU
Ceiling height, sun exposure, and insulation can swing the load by 20 percent or more. Always run the ACCalculator BTU calculator with your real conditions, then translate the impact with the multi-room planner if other rooms share supply runs.
Myth 2: SEER2 does not matter if BTU is correct
Higher SEER2 systems maintain capacity with less watt draw. Combine the BTU recommendation with SEER2 comparisons and the BTU and tonnage converter to estimate annual costs.
Myth 3: Oversizing solves humidity issues
Oversized systems short cycle and fail to wring moisture from the air. Use the comfort range guidance to stay within plus or minus ten percent of the target BTU and verify with the sizing summary.
Myth 4: Watt and amp ratings tell you load size
Watts or amps alone do not describe sensible and latent loads. Translate those specs into BTU with the tonnage converter to compare apples to apples.
Myth 5: All rooms can share the same load factor
Basements, lofts, and sunrooms react differently. Use the climate load adjuster to plan for zones with higher or lower demand.