How much R-22 is in a 3 ton unit depends on the specific manufacturer, model, line set length, and whether it is a split system or packaged unit, but generally a 3 ton residential air conditioner or heat pump contains about 6 to 12 pounds of R-22, which is about 2.7 to 5.4 kilograms. A ton of cooling equals 12,000 BTU per hour, so 3 tons is 36,000 BTU per hour, typical for a medium sized home. Factory charge for the outdoor condensing unit alone is often around 5 to 7 pounds, and additional refrigerant is needed for line set length beyond standard 15 feet, usually about 0.6 ounces per foot of 3/8 inch liquid line, plus indoor coil volume. Some larger or older systems with long line sets may hold up to 10 to 12 pounds total. The exact charge is listed on the nameplate of the outdoor unit as factory charge plus required field charge. Overcharging or undercharging affects efficiency and can damage compressor, so technicians weigh in charge according to manufacturer specs using superheat and subcooling measurements. Since R-22 is now expensive and phased out, knowing charge amount is important for estimating recharge cost.
1 votes
Marked as accepted