Cooling Air BEFORE it exits the grow room

So I was wondering....has anybody really tried to cool the air in the grow room as it exits the room? I've just been thinking where I am venting ANY heat into ANY other spot could be too noticeable. During the winter I plan to have a valve where the heated air (desmelled) can be vented into an area to warm the area up when I'm chillin in the area outside the grow, but when not there the air would be vented outside.

My idea - have the exhaust fan blowing into a PVC pipe big enough to handle the air flow. At one point there is a T joint, one way leading to the other room, one leading outside. The one going outside would enter a 30 gallon drum filled 1/3 the way with water and engine coolant first where the air would bubble up through the mixture and then out another pipe to the outside.

Would this provide enough cooling to keep from showing a "noticeable" heat exhaust during winter?

G'day... Ive been cooling the air out of my under ground room using a box (1 metre by 2 metres) made of wood and lined with garden plastic (The black stuff) and putting 2 or 3 partitions in the box using fine chicken wire and activated coal chunks and between the partitions put a fine mist garden sprinkler ( one per partition ) . So the air comes throu the box .. goes throu the first divide which is wet from the sprinkler then throu the second.. It works on the same princiable as a water evaporator airconditioner. you can never make the box to big.. the bigger the better.. you can even but an exhaust fan on the exit of the box to help the air throu.. If you can not find activated coal normal coal will do but wash it extremely well (both activated or not)
Hope this helps you..

Do you think diffusing (think of a diffuser stem from a bong) into car coolant and water would do the same thing though? It'd only be cooling the air from the 12/12 room the veg room would be under cfls so not much heat to remove.

I think it would work. But you would need a hella good fan to push the air into the water.

Thinking that a small fan mounted to the drum could help pull the air out of the drum...dont think I could get it air tight enough to change pressure enough to cause it to implode.

blown...

#1) will have 400W HPS in 12/12 room, just CFLS in veg room.
#2) Not inside a house, therefore different...add in direct sunlight on the "building", temps build up quick

(Look up my other post about my new grow room in the making)

I think you would need one hellava pump to force the air into the drum.. even if you stick a hose into a drum of water and blow throu it.. its hard.. I couldnt imagine a pump doing it... thinking of the size of the pipe you are going to be using for your exit air... build the box i mentioned before... its simple and it works

The PVC entering the drum (mind you this will only be 1/3 filled) would have a squirrel cage style fan attached to it pushing the air through. Now I dont know about you, but I think it'd have the force to move the air through, but maybe I'm wrong.

Having the water bubble through will require all sorts of valves and stuff to avoid liquid backlflowing.

Why don't you just make the pipe that goes outside a spiral or something similar, that spiralls THROUGH the drum, similar to a lab condenser, more specifically what is called a "graham condenser".

http://en.wikipedia.org/wiki/Condenser_%28laboratory%29

first of all get the car coolant idea out of your head, coolant is actually a worse conductor of heat than plain water, the only reason it is used in cars is to lower the freezing point of the water and to raise the boiling point and to lubricate the water pump and seals, it has no use in a grow room, if you were to run pure anti freeze in your car it would overheat because it is a poor heat transfer substance, second you need to think of how a thermal immage camera works, it detects heat on the surface of things, if you are growing in a closet that is in a room the camera will not see the grow, now if your lights were burning in a room that shared a wall with the outside then the camera would see it, but in reality a 400 in a closet is not going to be a significant ammount of heat to draw attention, think if you were sitting there with a small heater going, that would put down 4 times if not more the heat footprint of the light, but the idea of bubbling it through water is good, then you have to figure a way to cool the water, otherwise pretty soon you have a big tub of hot water, so yeah if you put this together leave the car coolant in the car