Air circulation ideas/help for my 10x20 space

[coughboss420]

I divided my 10'x20' room into a 12x10 flower room and 8x10 veg and clone area. I put a 18,000 BTU mini split in my flower room to help with the heat. I divided the room using the foam insulation board you can find at Home Depot. My thinking was that I could have a 6" and 8" inline fan pulling cold air in from the flower room to the veg to cool it since I am only going to be running one Gavita Pro 1700 LED in there. I set it up for the first time yesterday and it only seemed to make the room hotter, am I doing something wrong as far as air circulation ? I was going to try today switching it and having the 8" fan pull cold air in the room and have the 6" fan exhaust the air back into the flower room and see what that does. Has anyone experienced something like this and know what u should do, or am I going to have to buy a small portable a/c unit to cool my veg room ? Any recommendations or tips would be greatly appreciated.

 

[GarageGardener69]

Where are these fans positioned in this wall you made? How air tight are the two spaces? What are the temps in one room over the other? You may want a more passive approach with just one fan pulling or pushing air to the other room with a vent like feature that’s allowing flow through it.
I’m currently working on an air exchange/supply method to a spot that’s unconditioned.

 

[coughboss420]

So I raised both of my inline fans to the back corners of my veg room without any a/c and cut two 8" holes in the bottom of the shared wall to pull in cold air running ducting from flower room. I keep my flower room at 75 degrees and am trying to get my veg room never to go above 80-85 degrees. The two rooms seem pretty air tight and think I might have the temperature figured. My issue now is getting my room back light proof with all ducting going between the two rooms. The two 8" ducting that is bringing in the cold air is letting a little light in. Do you have any advice on how to block the light coming in my ducting without cutting off the strong airflow.

 

[Nixs]

So I raised both of my inline fans to the back corners of my veg room without any a/c and cut two 8" holes in the bottom of the shared wall to pull in cold air running ducting from flower room. I keep my flower room at 75 degrees and am trying to get my veg room never to go above 80-85 degrees. The two rooms seem pretty air tight and think I might have the temperature figured. My issue now is getting my room back light proof with all ducting going between the two rooms. The two 8" ducting that is bringing in the cold air is letting a little light in. Do you have any advice on how to block the light coming in my ducting without cutting off the strong airflow.

You may try bending the ducting like an S shape, you may also cover it with dark pantyhose

 

[Sidram420]

You may try bending the ducting like an S shape, you may also cover it with dark pantyhose

Be careful with your bends the tighter you make them the more you actually restrict the air flow every bend cuts back nearly a quarter of air flow

 

[Nixs]

Be careful with your bends the tighter you make them the more you actually restrict the air flow every bend cuts back nearly a quarter of air flow

That's true if he bends in a Z shape not an S

 

[Sidram420]

That's true if he bends in a Z shape not an S

Also holds true with s shaped bends when you bend in a z you lose more than a quarter the s still restricts air flow especially adding in more than one bend if you do one bend probably won’t restrict flow at all or barely noticeable but adding two or more will put strain on your whole system especially an automated system source 25 years of hvac installation and service

 

[GarageGardener69]

Also holds true with s shaped bends when you bend in a z you lose more than a quarter the s still restricts air flow especially adding in more than one bend if you do one bend probably won’t restrict flow at all or barely noticeable but adding two or more will put strain on your whole system especially an automated system source 25 years of hvac installation and service

What type of S bend we talking here? Gradual one or like a real tight one over like a foots span?
also to what affect does the size of the pipe and also the length of pipe have with turns and what not?

 

[Sidram420]

What type of S bend we talking here? Gradual one or like a real tight one over like a foots span?
also to what affect does the size of the pipe and also the length of pipe have with turns and what not?

A gradual bend in the pipe will not create any noticeable restriction but if you make an s like it is shaped with the slight hook or create a 90 degree angle it will cause air flow restriction and stress the fan or handler. the length of the ducting would only be a matter of concern if using a smaller fan like 3cfm which is standard house fan rating if your using anything that is 7 or higher the length will be okay long as your not trying to push the air fifty plus feet I’d imagine your run is probably pretty short for just exhaust maybe ten to twenty feet and yes the size ducking should be rated for your fan for instance a six inch inline fan hooked up to a 8 inch duct line will create a void in air space and will not remove the air properly leaving warm air to collect in pockets of the ducking same goes for smaller than needed like reducing a 6” fan to fit a four inch duct would create back pressure on the fan actually making it to where you remove less air than you think you are air takes the path of lease resistance always unless forced to do otherwise so kinks bends loops etc should be avoided or made as minimally as possible

 

[Sidram420]

With turns the farther from your air handler you are the greater the pressure loss so if you have a fan rated to remove 9 cfm from a room at a forty foot run that is rated for a straight pipe no bends so every bend you add that’s tight and not flowing I would subtract 1 to 1.5 cfm that’s cubic feet per minute of air removed

 

[Nixs]

With turns the farther from your air handler you are the greater the pressure loss so if you have a fan rated to remove 9 cfm from a room at a forty foot run that is rated for a straight pipe no bends so every bend you add that’s tight and not flowing I would subtract 1 to 1.5 cfm that’s cubic feet per minute of air removed

What if he covers the end of the duct with a pantyhose? You think it will put more stress on the fan.

 

[Sidram420]

What if he covers the end of the duct with a pantyhose? You think it will put more stress on the fan.

No it should act as a filter for small particles like hair dust etc but is not thick enough to add any restrictions if your room is 10x20 and you have a fan rated for 9 cfm or higher even with a charcoal filter mind you proper size filter example 6” fan 6” filter you would be good it would remove all the air in the room within 20 minutes or circulate all the air within twenty minutes your key thing is the placement of the fan and filter you want it to have good even flow on all sides if possible Example would be 10x20 room permitting no ceiling or hanging obstructions you would measure out around 5 foot off the ten find your center of room and place there but if you can’t do that just try to keep away from the walls as it will pull air from the open area still but will be wasting power pulling air off the wall as well and not working 100 percent they way you intend it to hope that helps a little I’ve had to place mine and move a few times till I found the best placement I grow in a 20x20 space and use a infinity 12 inline exhaust fan as well as a 12 inch inlet fan I run two hlg 650 rspec my room temp hold between 77 and 80 at all times running a portable a/c to keep under 80 I also use the infinity inlet fan so to keep my exhaust and inlet in sync

 

[Nixs]

No it should act as a filter for small particles like hair dust etc but is not thick enough to add any restrictions if your room is 10x20 and you have a fan rated for 9 cfm or higher even with a charcoal filter mind you proper size filter example 6” fan 6” filter you would be good it would remove all the air in the room within 20 minutes or circulate all the air within twenty minutes your key thing is the placement of the fan and filter you want it to have good even flow on all sides if possible Example would be 10x20 room permitting no ceiling or hanging obstructions you would measure out around 5 foot off the ten find your center of room and place there but if you can’t do that just try to keep away from the walls as it will pull air from the open area still but will be wasting power pulling air off the wall as well and not working 100 percent they way you intend it to hope that helps a little I’ve had to place mine and move a few times till I found the best placement I grow in a 20x20 space and use a infinity 12 inline exhaust fan as well as a 12 inch inlet fan I run two hlg 650 rspec my room temp hold between 77 and 80 at all times running a portable a/c to keep under 80 I also use the infinity inlet fan so to keep my exhaust and inlet in sync

I appreciate your reply, thanks a lot

 

[Jimmy Slade]

So, you're planning on flowering in a 10 x 12 with a single Gavita 1700?