A 9 ton AC unit is a large air conditioning system that is capable of cooling a large area, such as a commercial building or industrial facility. It is typically used in areas where a large amount of cooling is needed, such as in a large warehouse or factory. The size of a 9 ton AC unit is determined by the cooling capacity of the unit, which is measured in tons. A 9 ton AC unit is capable of cooling up to 72,000 BTUs of air per hour, which is enough to cool a large area. The unit is also capable of producing a large amount of air flow, which is important for cooling large areas. The unit is usually installed outdoors and is powered by electricity. The unit is usually connected to a duct system, which distributes the cooled air throughout the building. A 9 ton AC unit is a great choice for large commercial and industrial facilities that require a large amount of cooling.