thanx for the advice man, i here wat ur sayin about if i was to do it i need the smaller one push and bigger 1 pull but thgats doable wiv mw set up,, the hydro shop i got the fan from he claimed it was better to push than pull ? he sed if u cud see air u wud see quite clearly that pushing is better, i took the guys advice obviously as i am a nooby, i am about to finish my first grow, and thought i wud pose the question so i dont get a hotspot on my se4cond grow, but its obvious i need more fan power or just use independent fan to deal wiv the cooltube !!, but thanx for ya input man all replies i get i rearly appreciate it. cheers !!!!
ps av to internal oscilating fans in the tent !!
the person in the hydro shop is wrong.
i will give you the facts in laymans terms.
laymans terms :
http://en.wikipedia.org/wiki/Layman
it is better to pull air with a fan, the same way as an aeroplane pulls a plane through the air with its propellor, it does not push the plane, that design has been tried tested and failed.
to push a plane you need a jet engine, you can have one or two of them on the tail wings.
it is better to push air with an air compressor which uses a pumping action to produce its air flow rather than a spinning prop.
the cars in the eighties used compressors with pumps to activate the central locking system, you could cut a tennis ball in half put it over the cars door lock and thump the ball hard and the forced air in to the lock used to activate the central locking and open the whole car, you could then remove the locking petrol cap and take it to a ford garage and get them to match a key as you have lost it, after they gave you the key which fitted the locking petrol cap it was the same key that fitted the ignition. clever eh! we did it all the time.
try pushing the air in to the lock with a fan.
the compressor can produce very high forces of pushing air the same way as your lungs, try blowing a candle out from over a foot away , now try sucking it out, that is the facts.
a turbo is very good at pushing and pulling air as it uses a steel or ceramic impeller that forces air from the side to the front or rear, and not a propellor.
the air in a grow room does not get hot enough to damage your fan, just suck the air out with your fan like other growers do the world over.
a decent fan will easily take 50c (122f).
if you need to push it out to keep noise down then so be it.
the only thing i can suggest is pull the air the longest duct, and push it out the shortest duct.
