Cooling my hood

if the dr90 has six inch ports get a six inch inline fan... its just easier...

six inch cool tube, six inch ducting, six inch fan, six inch carbon filter..... easy

if it has the five inch ports get the four inch fan.... bummer

don't forget the fan speed/temp speed adjuster

 

just spit it out...

what do you have, and what do you need and want to do...... why do you ask questions then answer my question with another question(almost the exact same one)

why was the six inch fan too much... you really need to spell things out here....

 

Happy growing I'm done

 

Well the 6"vortex is best, especially when hooked to a filter. If you can mount the fan outside the tent and endure the noise you will pick up even more room.
The fan inside the tent as well as other electrical devices help to build up heat...
The cooltube is great for getting the light closer to the canopy but, not as great to cool down the tent area.

With your size tent you are going to build up more heat than you want with your lighting etc.

If you can touch your cooltube and is not uncomfortable your 4" setup may be ok. In that case I would say you need to bring cooler air into the tent and a better exhaust.....

 

You only need a 10* temp drop to be in a safer zone and some strains like it hot....At 90* your plants will be ok but, during flowering your yield etc will be much better.

Your 4" is probably the right size to cool the tube but, the ambient temp outside the tent may be to high causing the overall temp to rise in the tent.

This time of year some geographical places are still hot and in the triple digits and as the days get shorter the temp will come down and get cooler in the tent.
You either need to lower the AC temp or, start your grow later in the year when cooler.
The only option I can suggest is to lower the temp in the room where the tent is and use a inline duct fan to bring in cool air.

Another factor when using a cooltube is that the shorter the ducting and less bends the hot air has to travel will help it be more efficient and lower tent temp some.

Using a scrubber also makes the process of exhausting hot air a little less efficient. So yes using a seperate fan for the light will help.

If your in veg stage you might try disconnecting the scrubber and pull fresh cool air through the tube from floor level to lower temps. When the ambient temp get's cooler outside and during flowering hook it up to control odor.

 

What is your ambient temp OUTSIDE OF YOUR TENT?

wow guy. keep the 4inch fan and four inch filter... use this strictly for ventilation. DO NOT RUN IT THROUGHT THE HOOD.

NEXT purchase a 6-8" INLINE axial fan hydrofarm or ecoplus or ebay htg.. you know the ones that cost a whoping 30 bucks.. Personaly i would opt for the 8 inch (always oversize things it will save you in the long run)

I have an 8" axial and as long as your sp is low it can push 200+ cfm all day.. use this fan to cool the tube.. basicly you want to make the air pull in from outside of the tent where there is no mj odor and nice cool air.. then pull the air throught the tube and exhausting the tent.. no need for odor control because its a closed circuit..

I gurantee you will have no more than a 5 degree split from ambient with this set up.

 

EDIT didnt read colas post above.. Sorry to repeat your sentiments.

oh and this guy is in canada there is no way his ambients are that high.. honestly I think you are restricting the air flow with reducers and probly dont have an effecient set up. Like I said use 2 fans one for vent and the other to cool the light and you will be golden. I think ive seen the 6" duct axial fans go for 25 bucks usd

 

Im talking about these
http://www.hydrofarm.com/image.php?image=/i/jpg/FNB6_6589.jpg&width=800&height=800

i dont advise putting the square peg in a round hole. I know if you had a 4" axial you can use those dryer vent louvers from hardware stores and pull out the louvers and a fan fits perfect in the square space..

the least ghetto way would be to build a wooden box and mount the fan inside of it.. then make round ports.

ghetto way would be foil tape the bitch to the tube..

but frankly that might still not work well. just get the inline axial like the link.. look on ebay no joke 20 bucks.

 

Using an axial fan for the cooltube will not work better.
I used a 6" axial fan to cool my tube and went to a 6" centrifical fan because the light was way to hot..Trust me on this one.

I would use the axial fan to bring in the fresh cool 75*(or less)air at the lowest point in your tent and leave your cooltube setup as is.
I know that a 6" axial fan bringing in cool air will help lower the temps in that tent...I know because I had a similiar situation and lowered my temps by 5-7*

Just going to have to experiment....

 

The green wire should be connected for safety where water is involved...Neveless it will work just fine not connected...Just be careful...

 

Yea cola I would recommend blower fans if you have multiple lights or a long duct run.. But I have had great success using the axial to cool lights in low static pressure enviroments as long as the duct run is short like it would be with a tent.. I dont know maybe its because I found a axial fan that was putting out 400cfm free air.. But i usually use a 8" axial in a 6" situation.. were you using a long duct run or did you have a carbon filter on it?

to op....

Temperature is a crucial. Optimaly you dont want to go over 80.. if it gets a little over 80 here and there you will only be slightly hurt.. did you have the 4" venting the tent at the same time? make sure you expel all your heat into a different room or out a window or something. You dont want to just raise the ambient temp in your room.

I mean you should be within 5 deg split from ambient (IE room tent is in 70.. and tent 75 F )

I dont know what to tell you.. If you are using the two fan method you should be good.. remember its always better to pull the air than to push it so place your fans as close to the exit and as far from the intake as possible. Keep bends to a minimal. and make sure to fully stretch the flex duct out so it is smoother for air to travel through

Im wondering if your tent is having a hard time getting air intake.. are the temps dif if you leave the door open?

Have you tried different thermometers? Yours could be off.

I would work on getting the ambient temp down in the basement.. are there any sources of heat in the room that u need to insulate from? maybe a evaporative cooler would work well (i have no experience with them) if u have low RH. u might need a ac.. good luck with that though.

Do you have any pics of how you have it right now?