"Simon Gardner" [dot]co[dot]uk wrote in message
...
In article ,
"Tom Bennett" wrote:

I've had a few arguments with people who've used these that *unless*
there
is a vent to take the hot exhaust air outside, the machines just add to
the
overall temperature in the room that they're supposedly keeping cool.
Most
of the "portable" (freestanding) units don't have this: they blow cool
air
out of the front (giving the illusion of cooling the room) - and hot air
(i.e. the heat taken from the air + the heat caused by the machine
operating) out of the back, thus adding to the overall heat in the room.

All these machines have the facility to vent to the outside. I have never
seen one that doesn't.

However the portable machines remain pretty crap - particularly (for
obvious reasons) the evaporative ones). I long ago abandoned them for a
proper installed split system which is operating very nicely, thankyou.

These are also common in offices.


despite innacurate previous posters ac in offices in major cities in the uk
is the norm, no office block in central London would survive without it,
take an aerial look at offices and you will see virtually every one with an
ac plant on the roof. Re portable units they are vented to the outside, are
very inneficient and noisy as the compressor has to be housed inside the
unit. Evap coolers are a total waste of money. Proper fixed split packs are
not expensive starting at about 800-00, far less than a central heating
system. there is a huge ignorance in the uk whereas in the u.s. the public
are far more informed.
Pete