Below is a list of Air Conditioning Systems manufacturers from Appleton, Wisconsin. Air conditioning systems remove heat from the air in a space through the utilization of a compressor, a condenser, an expansion valve, a thermostat and a series of motorized fans. In addition, air ducts or air handling equipment may be used too. Despite popular belief, air conditioning systems do not add cold air to a space but instead remove heat from the existing air, which makes the space feel cooler.