Best location for exhaust?

Out the top or bottom and why?

I'm getting ready to setup my first tent. I was thinking on exhausting out the bottom to pull the warmer air down to the plant.

I'm going to a thermostat to control the temperature inside of the tent.

Blue_Focus said:

Out the top or bottom and why?

I'm getting ready to setup my first tent. I was thinking on exhausting out the bottom to pull the warmer air down to the plant.

I'm going to a thermostat to control the temperature inside of the tent.

Click to expand...

You want your intake at the bottom and your exhaust opposite side at the top. Its going to get hot enough in there on its own. Remember heat rises, so exhausting out the bottom would be pointless. Draw your cooler air in from the bottom and exhaust out the top

honestly i might be wrong but i was looking through grow journals and im pretty sure i saw a member of ours called TCH in one of his grow journals he had his carbon filter on the floor next too his plants and he had a fan uptop in the tent pointing down too blow air from the top too the bottom. let me see if i can find the picture in question but i think you can do it if its super cold in your area. led's dont emit much heat and it gets cold this time of year.

I just reworked mine. Pulled the 6" exhaust fan and charcoal filter out of the tent. Discarded the filter entirely. I attached the fan to wall next to the tent. Now I'm venting my tent out the top. I bought one of those window vents and vent the old air out the window.

My grow light is a 1000w HID which produces some heat. I've placed a cheap 6" inline fan to the light to draw out the hot air, and heat the tent.
My plan is to draw fresh air in the bottom tent flaps, run 2 small circulating fans to move the air, and then remove it through the top and out the window.

I suppose either would work. Having said that I prefer to take my fresh air in low and vent out the top.

I’m gonna go against the grain here but never mind. Exhaust should be at canopy height, and intake should be on the ceiling, cold air and co2 both sink, we wanna pour that cold co2 through the canopy I use fans hung from the ceiling to blow the fresh air across the canopy as it’s sinking.

dragging your cold co2 across the floor and up a wall as it warms and is exhausted from the other end of the room is not optimal

This is a very solid question that I have thought about as well since I used to struggle with temps (bf I bought an oversized oil heater for my 5x5) and insulated between the floor and the removable mat with shop floor ergo mats.
Also air does funky shit and I wish I was able to actually see the air circulating. Think about all the resistance the air gets from objects, oscillating fans, exhaust pressure.. obviously heat rises but in a small space like a tent I would rather have the whole thing be about the same temp and not drastically different between ceiling and floor.
humidity control plays big into this as well. I use a humidifier to bump it up in the winter bc it’s like 20-30 rh without it! My exhaust only kicks on when my humidity threshold is reached.

I have my exhaust under the canopy. my intake is over the canopy but picks up co2 rich air from the floor outside the tent.
works very well and also allows me to hang my light at the very top of the tent without having fans and filters in the way

After setting up and running for a few days. I have found that the temperature and humidity gets high quickly.

So I have my fan pulling out of the top using an Inkbird IHC-200 when the humidity goes up. I'm only using it for humidity control. The humidity sensor is located at the center of the tent.

My grow tent is only 24 x 24 x 56.

I’ve had the exhaust exit via the top with the filter inside the tent at the top; the exhaust at the top blowing out through the filter placed outside, above the tent (my favorite); and, with the filter placed on the floor of the tent and exhausting out the top. I’ve not had any noticeable differences or issues by placing the filter in different locations.

I’d just place the filter and exhaust wherever is most convenient and see how it goes. If you have issues then change it up. Dialing in your grow is an iterative process and there isn’t one way to skin this cat.

For reference, I exhaust my tents into a lung room which itself exhausts outside when the room reaches a certain temp and/or humidity.

Parzival said:

I’ve had the exhaust exit via the top with the filter inside the tent at the top; the exhaust at the top blowing out through the filter placed outside, above the tent (my favorite); and, with the filter placed on the floor of the tent and exhausting out the top. I’ve not had any noticeable differences or issues by placing the filter in different locations.

I’d just place the filter and exhaust wherever is most convenient and see how it goes. If you have issues then change it up. Dialing in your grow is an iterative process and there isn’t one way to skin this cat.

For reference, I exhaust my tents into a lung room which itself exhausts outside when the room reaches a certain temp and/or humidity.

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Great wisdom sir

For me I had a thought a few weeks ago after a few years of “struggles” growing indoor
“Why am I exhausting out all the climate I am trying to create in my tent?”

Blue_Focus said:

Out the top or bottom and why?

I'm getting ready to setup my first tent. I was thinking on exhausting out the bottom to pull the warmer air down to the plant.

I'm going to a thermostat to control the temperature inside of the tent.

Click to expand...

On top bro heat actually goes up

Tha

youngmoney9 said:

On top bro heat actually goes up

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That's where I ended up with. I was worried that being in my basement that it would be too cold. But it wasn't the case.

secretmicrogrow420 said:

honestly i might be wrong but i was looking through grow journals and im pretty sure i saw a member of ours called TCH in one of his grow journals he had his carbon filter on the floor next too his plants and he had a fan uptop in the tent pointing down too blow air from the top too the bottom. let me see if i can find the picture in question but i think you can do it if its super cold in your area. led's dont emit much heat and it gets cold this time of year.

Click to expand...

Could be intake to remove pollen

NR613 said:

Could be intake to remove pollen

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Nah it’s not I don’t think, imo the best place/places to have them is canopy height and below, like I said earlier cold co2 sinks, so if our intake is at ceiling height, we want to drag that cold sinking co2 through the canopy, who cares what temp the ceiling is, there are no plants there

If you have proper air circulation with breeze fan(s) inside, it really doesn't matter where the exhaust exits. The air is being mixed/swirled anyway.

I've tested and taken data trying top and bottom with exhaust fans. CO2, RH, and temperature always stayed within 1% of each orientation whether the exhaust fan was on top or on bottom.

Have mine in my loft with a bit of ducting to the tent
It wouldn't be efficient probly and might need a bigger fan
But dam man talk about quieter

Cold air drops and hot air rises. Depending on your desired results you can do a lot of different combinations. I do intake low and exhaust high.