A 20 ton air handler is a large, industrial-grade air conditioning system that is used to cool large commercial and industrial spaces. It is typically composed of an evaporator coil, a condenser coil, a compressor, and a fan. The evaporator coil absorbs heat from the air in the space, and the condenser coil releases the heat outside. The compressor pumps the refrigerant between the two coils, and the fan circulates the cooled air throughout the space. The capacity of a 20 ton air handler is measured in tons, which is equivalent to 12,000 BTUs per hour. This is enough to cool a large space, such as a warehouse or a manufacturing facility. In addition to cooling, a 20 ton air handler can also be used to dehumidify the air, which is important for certain industrial processes.