1. Find the square footage of the room. Measure the length and width of the room with the measuring tape and multiply the two numbers together to get square footage. For example,
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The formula is simple. One ton of cooling equals 12000 btu. So a three ton A/C has a 36000 btu capacity.
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A 5 ton air conditioner is typically rated at 60,000 BTUs (British
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1 ton 288,000 BTUs/24 hours or 12,000 BTUs/hour.
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