Question: I have been told my house has a 2 ton air conditioner. Does this mean my air conditioner weighs 4,000 lbs? Answer: The first air conditioning or cooling was done in theaters by hanging tons of ice in nets and circulating theater air across the ice to cool the air. In turn the ice would melt. They calculated that one ton of ice would remove 288,000 BTUs in a 24 hour period or 12,000 BTUs per hour. Your 2 ton air conditioner may only weigh 170 lbs but it removes 24,000 BTUs per hour of heat from your house. Tonnage refers to a rate of cooling.