Inlines fans suck help......

Okay I just made a new grow room and added a 4''and a 6''inline fan,I run them all the time.And the room still gets up to 88-90 degrees towards the end of the day.Im flowering from 2aM to 2 PM....Is There a better way to cool.I dont want to run at night the fans are super loud.+rep

Fans will only cool a light as much as the temperature of the air it is using.

For example, the air in your house is 75 degrees. If you are using this air to cool a 1000 watt light the best temp you can achieve in your room will be 75 degrees. But this doesn't happen in the real world. You will get at least a 5 degree increase in temp with a 1000 watt air cooled light no matter what the fan speed is.

Sure sure sure you can get it down maybe a degree or 1 and a half degrees with a strong fan but it's not worth the noise hassle.

A 600 watt light will raise your temp by 3 degrees or so depending on the air temp cooling the hood.

So it all comes down to the temperature of the air you use to cool your hood. Preferably, if you can use air that is under 70 degrees to cool the lights, using no more than 250 cfm, you can keep your room temp around 80 degrees cooling two 1000 watt lights. Add 5 degrees for each additional 1000 watt light

OR

Lower your intake air by 5 degrees (around 65) to keep three 1000 watt lights cooled to around 80 degrees. Use this formula and you will never have problems again. Remember this rule of ambient temperature cooling your lights and you wont ever have to worry about overloading on CFM.

i flower from 6pm -6am to take advantage of the cool night air. i also vent the hot air outside thru a window. I have the end of the duct work at the top of the light and ballast as heat rises and it goes right outside.

DocDoom85 said:

Okay I just made a new grow room and added a 4''and a 6''inline fan,I run them all the time.And the room still gets up to 88-90 degrees towards the end of the day.Im flowering from 2aM to 2 PM....Is There a better way to cool.I dont want to run at night the fans are super loud.+rep

Click to expand...

I had basically the same problems, I tried to vent a 6x6x3 grow cab with 2 4" inline duct fans from home depot. They worked alright with just a light (Im using a 432w T5), but they couldn't handle the heat generated by my water chiller, so I splurged and bought a very powerful centrifugal fan, and that lowered my temps by 5 or 6 degrees. What is really important is to make sure you purchase a centrifugal fan. These produce MUCH higher air pressures, meaning that you can push air through ducting much more efficiently. Your typical duct fans are axial, which makes them much less powerful.

I have the hose with Coldair coming in under my lights pointing at the tops of the plants,Should I have this hose pointing toward my lights instead....Im working with 2 cheap 400's.........Oh im using good inlinefans I just thought it would cool the room better,With one 400watt the temps would be perfect,Also I have my ballast's on top of my growbox with a fan cooling them,But I keep my exhaust Inside the box,Should I move it so its higher and next to my ballasts........

i have 600 watt light in a meter square budbox, inline fan sucking through carbon filter and aircooled light, with enough duct to point out of window if gets to hot or on a cold day leave it in the room, works for me im 7am light on off 7pm

I disagree (strongly!) with flowering at night because of ambient temps being cooler, UNLESS you can still achieve a 10 degree drop in temperature when you turn the lights off. If you cant, dont bother. Plants need that night cool. They dont wanna be hot n nasty during their sleepy time.

I think you read to much into the 10 degree drop. I would bet he'll get a drop any time of the day by turnung off his light. I run my lights at night. room runs around 80 lights on. 74 with lights off in the day time.

I would get a 10degree drop easy....should I move my carbonfilter closer to my ballasts...

you trying to cool them down? i have my ballasts a way away from the plants because they give off alot of heat, plus a bit parronoid about fires, had a friend growing on loft had a couple of ballasts on top of each other ( i know stupid) but his house burnt down. And u could use one of your inline fans to pull in a fresh air feed if it gets to hot?