> Sheldon Koehler and I just had this discussion a few weeks ago. > > An external a/c is designed to shed energy through the (external) air > forced across the condenser. > > An internal a/c would seem to want an external inlet and external outlet, > while recirculating the cooled air. ie, two air flows: > > 1. it sucks in cooled room air, cools it more, and returns it to the room. > > 2. suck in external air, forces it across the much hotter condenser, > cooling liquid in the condenser, and exhausts the (room's heat) back to > external. > > If you don't have 2, then you're sucking in hotter-than-room air into the > room on top of the equipment's heat, and you're asking your a/c > to do a LOT > more $$$work and with less cooling results. > > You can prove this in your car by feeling the temp a/c vent when > the a/c is > on fresh and recirculate. The recirculate temp is much lower.
This is well known in big A/C Systems (in big sales centers or anything similar). You need some percentage of fresh air in a closed room, because the air is "used up". But cooling is more effective with a closed circuit. So big coolers mix the old air in the room with some percentage of fresh air, and blows it back into the room. Hermann To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
