Quick HPS Question

I'm hooking up my 120mm pc fan to my 400w HPS to keep it cool. Do I need to blow air on the reflector or blow air out?

First of all I don't think that fan will move enough air. It is always better to push the air through than pull it through.


https://www.rollitup.org/grow-journals/54294-papaya-hindu-kush-aerotub-journal.html

i'm not sure what you mean, i only have one spot of my hood to hook up a fan, and its the perfect size for a 120mm fan.

How hot does a 400w get? <=/

gets pretty damn hot, if i put my hand on top of the hood for more then a few seconds it burns the hell outta my hand. I'm not saying by a long shot my room is getting hot or anything, just for peace of mind I want it to be cool. My room is about max 79.8 and min 70.9 I'll post a pic of my HPS

toolage said:

i'm not sure what you mean, i only have one spot of my hood to hook up a fan, and its the perfect size for a 120mm fan.

Click to expand...

Some reflectors have 2 connections for ducting. Sometimes 1 connection is on the side and the second one is on the top. The reason you have 2 is so you can connect a fan (or flex ductwork from a fan) to one side of the reflector and connect a second piece of flex duct to the other connection so you can duct it to another fixture or out of the room.

You can use that fan but again, it doesn't move enough air. You should get a proper inline fan if you want to keep that light cool. If you look at my journal the last post I made shows a Mom/Clone closet with a 400w fixture inside and ducting going through the walls. If you look closely you'll see flex duct connected to each end of the light. Outside the cabinet I have an inline fan pushing air right through the fixture.

Alright cool, I see now. Well I dont have enough money right now, maybe next paycheck, to get all of that right now. Is it bad for the light not to have one or is it mainly just to keep the room cooler?

If you connect the fan to the light you'll be able to put the light a little closer to the plants without burning them. Any heat you remove from the light and exhaust outside the room will reduce the room temps too.

The light probably won't blow up or anything, if that's what you are asking, but it's highly advised to vent it. Much better for your plants.