AZCat
Graduate Poster
- Joined
- Feb 6, 2007
- Messages
- 1,672
I think of airconditioning as temperature controlled ventilation, but then I'm a Dutchman.
But as I'm also into rocket science, consider the following: In an aircraft's AC system ambient air of about -50deg C is compressed in the compressor stages of the engines, thereby heating it up to about 300 deg C. It's then cooled by leading it through a heat exchanger and consequently expanded, further cooling it to about 3 deg C to enter the cabin as nice cool air.
So is at an air cooling or heating system?
It's more than temperature controlled ventilation - it's controlling the temperature of the space by heating or cooling the air. It can also involve controlling the humidity of the space (by humidifying or de-humidifying the air), but not all systems involve that. Not all methods of climate control involve "air conditioning". Some use radiant heating, for example.
Malcom is correct that in a building such as the WTC towers, ventilation is provided mechanically via the HVAC system, as opposed to natural ventilation (such as operable windows). The towers, however, had their building envelope compromised considerably by the collisions and outside air was able to ingress through the new "openings".