2 Tents 1 Fan

[Brownboi419]

hello everyone I was looking on line of ideas of using 1 fan to exhaust 2 tents. The flower tent is a 4x8 the veg tent is a 4x4 tent. I have a 10 inch vortex exhaust fan I was thinking of using to pull thru a ac hood for flower tent and the whole tent for the veg . I had seen this idea on line and thought about giving it a go. Any input would be greatly appreciated

 

[crimsonecho]

That much pressure and air movement would dry your weed to crumbles imo. I wouldn’t hook the drying tent in this setup.

 

[Brownboi419]

No I was not going to hook up the drying tent. I am just using this diagram as a rough draft for the two tents if possible I know I might have to hook up a damper to even out the flow for both tents.

 

[crimsonecho]

No I was not going to hook up the drying tent. I am just using this diagram as a rough draft for the two tents if possible I know I might have to hook up a damper to even out the flow for both tents.

Yeah i was gonna say how does two different sized areas work with the air flow and pressure? Will the setup balance the negative pressure in both tents on its own? (I think it should but i am not knowledgeable enough to give recommendations on ventilation). I don’t have any experience with a setup like this, i just think the drying box hooked to an intake is a bad idea.

 

[Brownboi419]

Yea idk that’s why I am asking for input before I go and try it but if I don’t get any I might just give it ago with a damper on one end to help adjust the flow

 

[crimsonecho]

Yea idk that’s why I am asking for input before I go and try it but if I don’t get any I might just give it ago with a damper on one end to help adjust the flow

I am sure someone will help

 

[Jack og]

Well the idea is sound provided you have adequate “fresh makeup air “ to compensate for outtake or “return-exhaust “, idea is to exchange equal volumes of air in and out. Goal is to maintain 1-heat/cool, 2- humidity, 3-bring in fresh air with adequate co2.
If you can Calculate the volume of the tents, and correctly size the fan and have enough flow, it is just like any circulation air or ventilation systems.
Dampers restrict air flow as a method to control volume, but too much resistance causes blower motor to heat up so I would properly size that.

The “big ass box” is called a plenum, if u have a local sheet metal shop, have them make you a box out of sheet metal, as when u pull air , u create a vacuum which will collapse that plastic hdx box.

 

[Brownboi419]

Well the idea is sound provided you have adequate “fresh makeup air “ to compensate for outtake or “return-exhaust “, idea is to exchange equal volumes of air in and out. Goal is to maintain 1-heat/cool, 2- humidity, 3-bring in fresh air with adequate co2.
If you can Calculate the volume of the tents, and correctly size the fan and have enough flow, it is just like any circulation air or ventilation systems.
Dampers restrict air flow as a method to control volume, but too much resistance causes blower motor to heat up so I would properly size that.

The “big ass box” is called a plenum, if u have a local sheet metal shop, have them make you a box out of sheet metal, as when u pull air , u create a vacuum which will collapse that plastic hdx box.

I was thinking of leaving the window cracked or possibly pulling using my hurricane fan to pull fresh air from my basement into the room we’re the tents are.

Each fan I have is bigger then the space I need so that it would be adequate with filter aswell. I was referring to a damper since both the spaces are not the same size wouldn’t it be pulling the same air from each tent even though they are not the same size if they were to be just both hooked up with out a damper to restrict pulling to much from the 4x4?

I will look into if I have a shop near by.

 

[OldSmokie76]

My current set up is two tents with one fan. A small 2x2x4 veg tent vents directly to 5x5x7 flower tent. I use a 165 CFM 4" fan and filter set up. The fan runs full power at all times. The veg tent has one 4" inlet at the bottom and air exits the top sleeve. The connected duct from the veg tent enters flower tent at the low side of tent and out the filter and fan at the top. The total cfm combined is slightly larger than the fan rating and i plan to upgrade to 6" set up soon. Currently, the 1000k hps hood is not vented. I greatly advise you to take in account your heat of light sources from tent to tent. I veg with a 300 burple led. Not much heat is drawn into the flower tent. Previously used a 600led and heat was too much. The hps really needs to be vented out of tent individually in my case. All in all, my set up creates enough negative draw to pull the tent sides on each tent. Veg tent has all vents taped except one four inch sleeve opening. You can adjust/block the vents on the flower tent for fresh air exchange in there. With the size fan you have a good speed controller may be a wise investment. I'm no expert, but this is my experience with this situation. Best of luck sir.

 

[cemchris]

10in fan is fine for 2 tents. If you arent venting it outside I would just stick the carbon filter on the end after the fan and skip the whole box setup.

 

[Brownboi419]

My current set up is two tents with one fan. A small 2x2x4 veg tent vents directly to 5x5x7 flower tent. I use a 165 CFM 4" fan and filter set up. The fan runs full power at all times. The veg tent has one 4" inlet at the bottom and air exits the top sleeve. The connected duct from the veg tent enters flower tent at the low side of tent and out the filter and fan at the top. The total cfm combined is slightly larger than the fan rating and i plan to upgrade to 6" set up soon. Currently, the 1000k hps hood is not vented. I greatly advise you to take in account your heat of light sources from tent to tent. I veg with a 300 burple led. Not much heat is drawn into the flower tent. Previously used a 600led and heat was too much. The hps really needs to be vented out of tent individually in my case. All in all, my set up creates enough negative draw to pull the tent sides on each tent. Veg tent has all vents taped except one four inch sleeve opening. You can adjust/block the vents on the flower tent for fresh air exchange in there. With the size fan you have a good speed controller may be a wise investment. I'm no expert, but this is my experience with this situation. Best of luck sir.

I was going to hook up to the ac hoods and leave one end open to pull the air through the hood and up out the top sleeve opening.

 

[Brownboi419]

10in fan is fine for 2 tents. If you arent venting it outside I would just stick the carbon filter on the end after the fan and skip the whole box setup.

I have a 10 inch vortex exhaust fan 790 cfm also have a 8 inch hurricane exhaust fan 745 cfm which would be best to use? And would like to vent outside to help elimate the heat from in the room itself

 

[JWM2]

If those are your only choices then go with the smaller one. Do you have a speed controller you can use to turn it down even more? They sell them for $15-20 on amazon. They can cut down the speed of your inline fan by up to 50%. That way you can adjust it.

 

[Brownboi419]

Those are what I have. I also have a speed controller but had thought those had put a wear on the fan motors?I could go out and buy a smaller fan not really a big issue to do.

 

[JWM2]

It’s all about exchange rate. Do the math. 4x8x? 4x4x? Add them together. Then figure you want to exchange the air once per minute to every couple minutes. I have 65 cubic foot in my growing rack. I use a 180 cfm in-line fan and actually turn it down a little. I don’t need the air exchanged three times per minute. However it’s nice to have the ability to turn it up just in case.

 

[crimsonecho]

I was going to hook up to the ac hoods and leave one end open to pull the air through the hood and up out the top sleeve opening.

You can hook two smaller (or not) carbon filters on the each end of the hoods and pull air through the carbon filter. Wouldn’t that work for eliminating the box?
Get a splitter at the intake of the fan and hook both ducts to each end. You can hook one damper at the each intake of the splitter, or just hook one between the fan and the splitter (for different purposes) if you like, tho i don’t think you need it especially with a speed controler.

 

[Jbellsmoke]

Any of you using a hrv in any of ur setups. Just thought of hooking the one I have up this winter to help save some wasted energy.

 

[Brownboi419]

You can hook two smaller (or not) carbon filters on the each end of the hoods and pull air through the carbon filter. Wouldn’t that work for eliminating the box?
Get a splitter at the intake of the fan and hook both ducts to each end. You can hook one damper at the each intake of the splitter, or just hook one between the fan and the splitter (for different purposes) if you like, tho i don’t think you need it especially with a speed controler.

Two filters means having to replace just that two filters.
I had thought speed controls put more wear on the fan motors then needed?

 

[Brownboi419]

Any of you using a hrv in any of ur setups. Just thought of hooking the one I have up this winter to help save some wasted energy.

Nope but explain more lol I see Some diagrams now online

 

[Jbellsmoke]

Nope but explain more lol I see Some diagrams now online

So any exhausted air from room or tent that u taking outside passes through a little heat exchanger and transfers the hot exhaust air to the cool fresh coming in from outside. Figured it will work best when colder season comes in. I'm in Canada and these thing are now building code for new homes. I think it will work pretty good to heat my fresh air that I pull in at winter.