The AirCon is not a traditional Air Conditioning unit like you would find in your house or car. There are no compressors, condensers, or Freon in the AirCon. The AirCon actually is a combination of two heat sinks, two fans, and a thermoelectric cooler, also known as a peltier. Peltier's have been used to cool CPUs for quite some time by hardcore overclockers. Here is a brief description of what they are and how they work:
Peltier devices, also known as thermoelectric (TE) modules, are small solid-state devices that function as heat pumps. A "typical" unit is a few millimeters thick by a few millimeters to a few centimeters square. It is a sandwich formed by two ceramic plates with an array of small Bismuth Telluride cubes ("couples") in between. When a DC current is applied heat is moved from one side of the device to the other - where it must be removed with a heatsink. The "cold" side is commonly used to cool an electronic device such as a microprocessor or a photodetector.
So what we have is a thermoelectric cooler sandwiched between two aluminum heat sinks, each with its own fan. Then throw in a digital display to show the temperature of the air flowing through the unit, a switch to control the two operating modes, and a slide mounting system that occupies a 5.25†drive bay, and you have the PC AirCon PAC 400.