Split Exhaust Idea for Tent

rmax said:

Are you routing tent exhaust to outside of the building?

Once I routed my tent exhaust to outside through the basement window humidity and temps dropped.

Click to expand...

No, I have the exhaust going into the room.... someone suggested this way earlier in the thread. It doesn't seem to be a problem really.. the room is ice cold... I'm tellin ya, I'm convinced it's those damn LED drivers that are causing all the heat in that tent. I could be wrong but as soon as I turned those dimming switches up the heat was instant off those things. So I don't think the exhaust going into the room is a very big deal...

I have the unit set to medium and 65 deg, and I am at 85. Had it on high over night and was at 80. But my humidity is down to 30. Gonna water a few plants and I'm sure it will go up temporarily. And I am switching to 12/12 tonight so once these things start getting thicker I know the humidity will go up as well. Not too worried about it just want to get it a little more humid in the meantime.

As long as it isn't 100 deg in there I'm happy.

Peyote alexia said:

One reason to a window/split ac"s efficiency compared to a portable unit is it doesnt create negative pressure, so doesnt draw air in the room. Which makes it perfect for a closed system. Unless your running c02 you shouldn't have a closed system. You need at least a exhaust exiting the building. To then have what they call a passive intake. Take all this and a lot more into consideration. Make sure your extracting the hot air from above the lights. Make sure your intakes on the tent are in areas with good circulation. Make sure your air leaks to the room are in cool places. Every aspect here can change a degree or two so it all counts.
The main reason for exhausting outside even if it seems counterintuitive due to there being no temoerature difference. Is due to the fact that your plants perspire moisture in heat more. And the more they transpire the harder it gets to kool the air. Its a viscous circle. Dont beleive me google "is it easier to cool down dry air" the ac will lower humidity. Do enough to lower get to the threshold where the ac controls it easier and easier wjwth all these tactics
Just throwing my 2c in again

I just got my dual hose unit. Will be modifying it slightly. Then sharing my results on the exhaust/ac series setup. But won't be for a while

Click to expand...

Interesting.... well I'm gonna have to do some modifying and get my exhaust going out the window. The window unit sucks air from inside the room right? just wondering because if I put my exhaust out the window right next to the a/c, I don't want the a/c to just suck my exhaust right back into the room...

The most effective way your going to make a difference is directly extracting the driver heat out the window. It’s basically a tiny little heater, your AC is fighting it, a good led or any light with good wattage can heat a room up in the winter time pretty easy, it’s cake in the summer time. It’s much easier to heat a room, then it is to cool it. Place it into a box or some type of contain with a good amount of room, then using ducting vent it out the window, add a small a 120mm case fan, or in-line fan if u want to over kill it.

dnap420 said:

It’s basically a tiny little heater, your AC is fighting it,

Click to expand...

Good point. More googling....

"to heat a room of 100 square feet, you will need a heater that is 1,000 watts, which translates to 3,410 BTUs. "

Theoretically, if combined wattage of the grow equipment = 1,000 watts one would need an AC unit of 3,410 BTUs just to cancel the equipment heat. If outside is 90 and one desires 80 inside, more AC BTUs.

rmax said:

Good point. More googling....

"to heat a room of 100 square feet, you will need a heater that is 1,000 watts, which translates to 3,410 BTUs. "

Theoretically, if combined wattage of the grow equipment = 1,000 watts one would need an AC unit of 3,410 BTUs just to cancel the equipment heat. If outside is 90 and one desires 80 inside, more AC BTUs.

Click to expand...

Also consider outside temperature, most window a/c start to loss effectiveness after a certain temperature, regardless of size. Mine is a 8000btu, in between 20c to 30c it can cool a room it’s deigned for down to 20c, if temperatures rise past 30 it maybe will cool down to 22, hitting 40s it would struggle to make 22, even if I blocked off door ways to keep the air in, it’s generally to hot out to even cool the Freon, without cool Freon your Ac won’t cool regardless of how little of space your trying to cool. If I got a 12000 btu I probably would be better off, even then your still fighting a heat source. Deal with the heat source would decrease room temperature alone, while increasing the AC effectiveness.

dnap420 said:

Also consider outside temperature, most window a/c start to loss effectiveness after a certain temperature, regardless of size. Mine is a 8000btu, in between 20c to 30c it can cool a room it’s deigned for down to 20c, if temperatures rise past 30 it maybe will cool down to 22, hitting 40s it would struggle to make 22, even if I blocked off door ways to keep the air in, it’s generally to hot out to even cool the Freon, without cool Freon your Ac won’t cool regardless of how little of space your trying to cool. If I got a 12000 btu I probably would be better off, even then your still fighting a heat source. Deal with the heat source would decrease room temperature alone, while increasing the AC effectiveness.

Click to expand...

mannn. you lost me at Celsius. just took a whole physical geography course revolving around Celsius to Fahrenheit conversion and dont remember a lick of it.

but my extension cables should be coming within the month for the drivers so I can place them outside of the tent... I was just going to mount them on the wall.... but you are saying put them inside of some kind of vented enclosure.... I guess I could mount them on the wall...use some plywood to build a box around them and put my tent exhaust through this box and out the window... plywood is cheap so this wouldn't cost very much..

If mounting them on the wall doesn't solve all my problems I will consider this... kinda iffy about enclosing all that heat in a small space but I guess the fan would keep it cool enough to eliminate any fire hazards.

I officially am in flower now though... just switched to 12/12 today. 11 am -11 pm = lights off. AC is set to 69 on medium and I am at 80 deg. 74 deg outside... Still a whole lot better than it was with the portable ac unit.. My humidity is dropping and that's the only issue right now besides having the AC working harder than I would want it to ideally...

Humidity is at 40%, but the hotter it gets it seems the lower the humidty goes as the AC works harder to lower the temp. All the while I have a humidifier set to 55% going non stop inside the tent...

Little glimpse into the setup

Awesome to see you making progress!

Could you route the AC output directly into the tent? AC should work less. Dehumidified.
Would need to adjust for flow/pressure.

Just a thought.

SoN3at said:

Interesting.... well I'm gonna have to do some modifying and get my exhaust going out the window. The window unit sucks air from inside the room right? just wondering because if I put my exhaust out the window right next to the a/c, I don't want the a/c to just suck my exhaust right back into the room...

Click to expand...

Correct. Although as mentioned it will still lose some efficiency if you exhaust hot air near it. Like a hotter day

Heatinsulated hose from AC unit, since the hose will heat up. If you got a fan in the tent, this heat will spread.

If I were you I would also seriously consider getting a hole in the wall. Your exhaust air goes out the window, and intake is in the window? You're gonna suck some of that hot air back, since you have relatively high and low pressures next to eachother (unless your exhaust hose is pretty long and far away from intake, of course).

I also find a powerful fan makes it worse in summer. A small USB fan for minimal circulation, so that you dont mix the hot air in the top with the cooler air taken in at the bottom. When heat is an issue you really want an even flow from the floor going upwards so the plant doesn't sit in the hotter air. In winter it's the opposite, air intake above lamp and exhaust in the bottom so you don't have to have a heater (it gets freezing cold here).

I find it very weird your ac is not capable of cooling it down more, though. Sup with that?
Im running HID's, at 29C outside I still was able to keep tent 29C without AC. But like I said, tiny fan only, and exhaustfan running at 40% (something like 80m3/h)

Just my thoughts anyway, hope you figure it out

TintEastwood said:

Awesome to see you making progress!

Could you route the AC output directly into the tent? AC should work less. Dehumidified.
Would need to adjust for flow/pressure.

Just a thought.

Click to expand...

No idea how i would do that. Will have to think on it.

Enanthate said:

Heatinsulated hose from AC unit, since the hose will heat up. If you got a fan in the tent, this heat will spread.

If I were you I would also seriously consider getting a hole in the wall. Your exhaust air goes out the window, and intake is in the window? You're gonna suck some of that hot air back, since you have relatively high and low pressures next to eachother (unless your exhaust hose is pretty long and far away from intake, of course).

I also find a powerful fan makes it worse in summer. A small USB fan for minimal circulation, so that you dont mix the hot air in the top with the cooler air taken in at the bottom. When heat is an issue you really want an even flow from the floor going upwards so the plant doesn't sit in the hotter air. In winter it's the opposite, air intake above lamp and exhaust in the bottom so you don't have to have a heater (it gets freezing cold here).

I find it very weird your ac is not capable of cooling it down more, though. Sup with that?
Im running HID's, at 29C outside I still was able to keep tent 29C without AC. But like I said, tiny fan only, and exhaustfan running at 40% (something like 80m3/h)

Just my thoughts anyway, hope you figure it out

Click to expand...

Not sure you read whole thread

TintEastwood said:

Awesome to see you making progress!

Could you route the AC output directly into the tent? AC should work less. Dehumidified.
Would need to adjust for flow/pressure.

Just a thought.

Click to expand...

I think ac would still work just as hard or harder. The sensor that it uses to determine how hard to work is measuring the room temp. Routing the vents direct into tent would warm the room and cause it to work even harder

SoN3at said:

I think ac would still work just as hard or harder. The sensor that it uses to determine how hard to work is measuring the room temp. Routing the vents direct into tent would warm the room and cause it to work even harder

Click to expand...

I don't think you know how an ac unit works, it compresses gas to make it relatively hot and cool it down with the room temp, and then expands it again. Google it.
Point is, the ac won't work well at high temps. It uses your roomtemp to cool down the gas inside, which expands to further cool down the air in your room.

Enanthate said:

I don't think you know how an ac unit works, it compresses gas to make it relatively hot and cool it down with the room temp, and then expands it again. Google it.
Point is, the ac won't work well at high temps. It uses your roomtemp to cool down the gas inside, which expands to further cool down the air in your room.

Click to expand...

Well. Only way i see to directly vent ac in here is to do what i did with the portable and shove hoses over the vents or maybe mold one of those rectangle style ducts over the front

SoN3at said:

Well. Only way i see to directly vent ac in here is to do what i did with the portable and shove hoses over the vents or maybe mold one of those rectangle style ducts over the front

Click to expand...

That wasnt really my point but yes, you should have the unit inside the tent with a hose that blows exhaust outside your house. Preferably an insulated one, since that air is hot as shit. But you already know that.

Enanthate said:

That wasnt really my point but yes, you should have the unit inside the tent with a hose that blows exhaust outside your house. Preferably an insulated one, since that air is hot as shit. But you already know that.

Click to expand...

I can't put a window ac unit, inside the tent...

The heat wave ended here. Temps just cracked 79°F in my house. LOL

We have 35° here right now. I have an AC 9000btu in the grow space and moved the fresh air intake inside a room that I also run a AC. Works good

Got the drivers out of the tent. Looks like ive dropped about 4 degrees so far. Maybe a little more.

Overnight temps have been cool here. The temp is down to 74° F in the house, 77° F in the basement right now.