Hey guys. So i decided to upgrade my vivosun 4x2 tent with a 4x2 gorilla lite line with extention so its about 7 ft tall now. I also upgraded my light from a vivosun fs1000. To the HLG 300l Rspec. I was pretty reluctant to do this now as my plants are in fairly early flower. But having everything here i couldn’t help myself. I have already noticed a conciderable jump in temperature. I placed a fan above my light to cool the control board itself. But that did nothing to change the temp in the tent. I am still using the 4" duct fan. Im am wondering if a bigger fan would do the trick? I was looking at one of these infinity fans that claim to heat and cool. Does anybody have experience with this product? My temps are reaching about 80 upper 70s. But i live in the mountain’s where it is rare to have an AC. I fear the mid summer temps will be too much in my tent. Any suggestions or inputs? I appreciate it in advance. Thanks!
A 4” Inline should handle a 2x4 tent temperature is directly related to the temperature in the lung room 80 is not to hot when you get over 90 that’s a problem if your not going to use AC you can change your light cycle so the lights are on at night when temps are cooler also venting you tent outside helps with temperature and humidity
I had the same problem when I got my HLG 260 90+ temps (older version) I moved the transformer outside of my 3x3x6 tent. Hope this helps.
Some additional heat would be expected when increasing light 2.5X. Increasing air flow will help
Are they auto? If so i go to a 6/2 5/3 light schedule myself. On a 5/3 with all photo atm. Temps far easier to regulate. They seem to love the naps also.
Do you have it just pulling and pushing from one open vent I make a circuit I do my stuff a lil weird but it works I pull air from on top and evacuate it through pushing though a carbon filter yes I know not reccomended then I completely open the oper top vent so the negative pressure keeps air circulating 5 degree diff with fan full blast amd just opening the opener top vent to breathe inhale and exhale seems to be doing amazing so far
She’s in a a 2x4x6.4 6 inch fan ac infinity with carbon filter it’s been over 100 and the room with 2 rents both stay between 73-80 canopy temp
And top temp above the light is 83
Literally just opened one chute and have no duct using a carbon filter as a dust cover for the big hole staying right on target!!!
Get a 6inch exshust system for ur tent to replace the four inch and then use the four inch to bring cooler air back into ur tent thats what i do but ive only got two four inch inline fans
Thats a great idea. That would probably be just right. Thank you!
Yeah i think a bigger inline can only benifit.
Yah i think it will aswell .i know i have to upgrade my inline fan to get rid of heat
So, I’m no lighting pro, but I recently bought an hlg 350r, and have been doing a lot of reading on growing with led’s. Apparently optimal temp is 80 to 82 because led light does not heat up the leaves to photosynthesis correctly, and optimal leaf temperatures need to be 80. So I think you’re probably in good shape. Here’s a little snippet.
Specifically, if plants are being grown in optimal conditions at 75 °F under HPS lighting, the ambient air temperature would need to be raised by 9 °F or more under LED plant lights to achieve the same optimal leaf surface temperature to optimize plants’ metabolism
Same issue. Bigger light was great except temps crept into the high 80’s. AC Infinity Fans helped. Its good kit and will cycle up and down for you but that will only help if the lung room cooperates with cooler air. In my case some of the guys on here also helped me punch outside with an exhaust system that I can run completely inside while I pull outside air into the lung room. Or I can exhaust everything outside. Its overkill for the most part but it works. On the more pertinent AC Infinity question I am a big fan. Pun intended. 
Looking for opinions on the following design
Filter Manufacturer shows both inside or outside configuration.
I believe the out of tent and vent into the attic will work in summer really well and allows more grow height.
and
@DEEPDIVERDAVE looks about right though I would get some others opinions on here. I have a similar setup with the filter in the flower tent outside the tent to provide more headroom. The flower tent has the filter inside but I elected to vent mine on two different lines which helps me control the two environments differently if I like. I put an eight inch on the flower tent which was overkill and a six inch line on the veg tent. The AC fans generally provide plenty of airflow but I also have a spare old fan like you show set up on a switch that I can use to push air into the tents if I want. Finally, I set mine up so I can switch it over to run all inside. No push of the air outside the room if I do not want it. Dense heavy humid air outside the room for example pushes back so to speak. Hey @dbrn32 if you are still out there can you take a look for Dave? It was your genius that helped me set my outfit up and I couldn’t be happier. Except you removed the airflow and environment as my excuse for bad grows I suppose. Which is inconvenient sometimes.
Ha, too funny!
@DEEPDIVERDAVE every space will have subtle differences that could make doing one thing way better or worse than everyone else. As far as setting up your ventilation goes, the different options will all provide some pros and cons. In my experience having your filter inside of youe tent will provide the best scent removal and longest service life, but will impact the amount height for your plants. Moving filter outside of tent will open up the space, but blowing through inside of filter reduces surface area of filter media, and can lead to lower filter performance and service life.
A few points in addition to above… Carbon filters are sensitive to humidity. If your attic gets stuffy like mine in summer could render it ineffective. The length of duct and amount of bends in duct will add static load to your fan. The more duct and bends you have the less air it will move. Also, if you were to have exhaust routed near intake you could be recycling warm co2 deficient air back into your tent.
To say it has to be one way or another isn’t really fair. A slight change in temp of your home vs everyone else could allow you to do something the rest of us can’t, or make what just about everyone else is successful with a battle for you. But generally speaking, i would say keeping fan and filter inside of tent with just a short straight piece of duct connecting will give you the best performance out of your fan and filter.
I can’t mathematically prove it but my experience tells me you need a 8 inch fan if you are going to hook the 2 tents together like your diagram…I run a 8inch on my 48x48x80 tent because the 6 inch I did use let the tent at times get too hot so I moved the 6 inch to my smaller tent that was also struggling with heat using a 4 inch fan…now both tents are easily controlled without having to run the fans at max speed all the time. just something to consider
@Plutarch when I set up my grow room since I have access to 2 windows I decided on a double negative air environment. I placed my carbon filter covered within the tent and ran it to a double fan at one of my windows. I attached the 6” tubing directly to the exhaust fan and left the other side to vent the room itself. Now as long as the rooms door is shut when I open my tent up initially that first fragrant puff of loveliness is contained in the room and shortly thereafter pulled out as well. Between the 2 negs you’d have no idea the plants were in the middle of veg lol. Keeps wifey off my tookus lol.
She got a little disturbed in Nov when I had 3 separate 12 day dry rotations with my 10 VERY pungent ladies lmao. You could smell them everywhere.
I’m a firm believer in ‘Happy Wife = Happy Life’
Or at least that’s what she keeps telling me……
@Fieldofdreams Sweet setup, With access to air and light. Jealous. Mine punches out to the garage for air since that part of the basement is like a bunker with no other exit without running through the finished portion with all the people living in it. I also like the nice clean lines. My first set up was all connected correctly but had so much extra ducting and loops and turns it was a wonder the airflow worked at all. I remember a project straightening and shortening duct lines which alone dropped my temps a couple of degrees with no further modification. As to the Happy Wife thing … smart man. Unhappy ones are both miserable and expensive in my experience. 