can fan..... push or pull?

irishwyrick

Active Member
I have a 6in H.O canfan to cool my 1000w hps light, should i set it up to push air into the light or pull air through the light? I would like to have it pulling air through the light but i dont know if the heat from the light will mess up my fan.
 

wiseguy316

Well-Known Member
you aren't cooling a wood stove, with air across the light it won't be very hot, but it would heat up and enclosed grow room.
 

ImTheFireMan

Well-Known Member
you need to be pulling that hot air away from it, the heat will not be an issue. they were made to pull hot air out of one place and put in another.
 

woodsmaneh!

Well-Known Member
you want to push that way if there are any leaks fresh air blows in.

If you suck any holes or rips will draw air from your grow room and send it out to the world.

I came in one day found 1 4" duct had broken, glad I was pushing and not sucking.

Peace
 

ImTheFireMan

Well-Known Member
the best thing to do is to pull the hot air being produced by the light and exhaust it into another room if you can, or at least to the bottom of the room.
if you push air into it, depending on where your intake side of the fan was, all you're doing is mixing room temp air with hot air.
you will have more heat issues in your room if you push air into the hood than if you were pulling it out of there.
 

fred flintstoned

Well-Known Member
Pulling is more efficient, but there must be a filter downstream. If not, pushing will help keep the funk out of the airstream. This is due to grow room air being sucked into the cracks in the ducting. It seems to me that no matter how well you tape and seal ducting, eventually it will leak. Heat will cause the tape to fail sooner or later. Murphy's law says it will happen when you're not home!
Fred
 

irishwyrick

Active Member
i set it up to pull from the light and exhaust into the attic. its set up to have negative pressure in the tents
 

fred flintstoned

Well-Known Member
Read the specs at your manufacturers website. I'll bet their engineers recommend pulling air as more effective/less strain on the bearings/motor.
Don't forget the filter at the end of the line.
Fred
 

irishwyrick

Active Member
Read the specs at your manufacturers website. I'll bet their engineers recommend pulling air as more effective/less strain on the bearings/motor.
Don't forget the filter at the end of the line.
Fred

thanks i'll look that up right now.

what kind of filter should i run? im light on cash after buying $2k worth of stuff for my grow allready so what can i do on the cheap?
 

R2F

Active Member
The reason you want to PULL air through is so that you don't have a lot of pressure on your ducting.

When you PUSH air through, you increase the pressure on the seals of your duct to light fixtures. By doing this you increase the maintenance on your ducting because it tears or slips off your hoods.

If you pull air through, the ducting STICKS to your lighting regardless of the position or how tight your hose clamps are that keep the ducting on the light fixtures.

If you push the air through and the hose comes off at light number 1, you are not circulating through lights 2, 3 and 4. This is bad for 2 issues:

1. If you have a sealed room, you are now pushing outside air into the bloom room, and then venting dank air to the outside world.
2. If you do not have a sealed room, you are no longer pushing air through the carbon filter and are venting dank air to the outside world.

All in all, pull is easier on the ducting, and more likely to keep your shit from flying apart. Not to mention the damage a 6' section of ducting is going to do to your girls when it flies off your light fixture.

Edit: Just an aside, don't plug an 8" can in when it's in your hands. I almost chopped a finger off that way ;) sandpapered 2 of my fingers bloody lol.
 

OMG LS6

Well-Known Member
Ive always thought that pushing was more efficient that pulling...This is why performance cars are RWD or AWD compared to FWD...I dunno pushing a car is a lot easier than pulling one LOL...Maybe this analogy is irrelevant to this situation
 
Top