Fresh Air Exchange and Co2?

[bobthethcguy]

So, I started down this rabbit hole by doing a search on the forums for the Exhale CO2 bags to see what the general thoughts were.

As it turns out, I wasted my money. It's ok, I've spent waaay more on waaaay dumber things.

BUT, this led me to several posts that mention the plants need fresh air. I have my ACI controller set to turn Intake/Exhaust fans on only if Temps go above 78f or RH goes above 68%. I've been running for a week and based on the graphs my I/E fans have yet to cycle air. I tried setting them to CYCLE with 1min on, 59m off but the controller does NOT like that, the goal was fresh air once an hour, but even manually running it for a minute killed my environment.

Is it enough of an exchange when I open the tent to do my morning inspection? Should I go ahead and hang the CO2 bag? I've read they are horrible alternatives to Co2 burner or straight gas and that adding Co2 can really change variables. If these bags only produce less than a tea candle and I'm only exchanging air once a day maybe I should have it.

Thanks as always!

 

[Graham.Bagg]

I run my exhaust fans continually, and have set points to bump up speed if heat/humidity reach a certain point.

I have a 4” flexible aluminum duct that supplies “fresh air” to make up for loss. I run a SLIGHT vacuum in my tent.


Sugar water and wine yeast will also produce CO2

 

[amneziaHaze]

Tea light candle will make a 3x3 around 1600ppm

 

[bobthethcguy]

I run my exhaust fans continually, and have set points to bump up speed if heat/humidity reach a certain point.

I have a 4” flexible aluminum duct that supplies “fresh air” to make up for loss. I run a SLIGHT vacuum in my tent.


Sugar water and wine yeast will also produce CO2

The ACI Automation settings had them run continuously and I couldn't get the tent to stabilize to desired VPD/RH/Temps even with Max set to 10. So I switched to a custom setup.

 

[Newty]

I run my ACI intake and exhaust at a constant speed of 2, my intake is smaller then my exhaust so negative pressure stays in the tent.
I have an advanced Automation set at 78 degrees with a 2 degree transition. Meaning my fans will run at speed 2 and when temp hits 78 goes up to speed 3 and every 2 degrees higher in temp it gets, the fans go up another speed.

Do you have a humidifier? Do you run it inside or outside the tent?
I feel humidifiers (at least with an intake fan on tent) work better when outside tent and directed so the mist goes through the intake fan, then all the air coming into the tent will be with mist from the humidifier.
Seems to keep the tent more consistent and don't lose as much humidity because it's in all of the intake air.

Most of us have never supplemented co2 or even measured it for that matter, sure it has it's benefits but with a sealed room and a very powerful light. Need to be able to run a high ppfd with co2 supplementation.

 

[FloridaMike]

how/where are you set up? closet? bedroom? etc. are you, or can you set up a "lung room"? that is what i'll be doing

 

[Newty]

I also see another potential issue.

You're running your fans with a temp AND humidity trigger, you really should only have 1 trigger per piece of equipment.
If your environment happens to hit both triggers at once, the controller may make it act funny because it's trying to adjust to 2 different triggers at the same time.

I'm guessing you probably have other settings active that are counteracting the settings you're trying to setup.
If you tell me exactly what you want your fans to do, I will send you step by step screen shots of how to set it up.

 

[LoveGrowingIt]

Doing yoga in my grow room will set off the alarm on my CO2 monitor.

 

[FloridaMike]

I also see another potential issue.

You're running your fans with a temp AND humidity trigger, you really should only have 1 trigger per piece of equipment.
If your environment happens to hit both triggers at once, the controller may make it act funny because it's trying to adjust to 2 different triggers at the same time.

If you tell me exactly what you want your fans to do, I will send you step by step screen shots of how to set it up.

i may hit you up on that as well once i'm ready to go in a few weeks. they have poor instructions, they're not very intuitive and there aren't any good in depth yt vids out yet. i've figured out a lot, but am sure i'll have some ?s. i'm planning doing almost exactly as you with added lp gas Co2

 

[Newty]

i may hit you up on that as well once i'm ready to go in a few weeks. they have poor instructions, they're not very intuitive and there aren't any good in depth yt vids out yet. i've figured out a lot, but am sure i'll have some ?s. i'm planning doing almost exactly as you with added lp gas Co2

I agree, the instructions suck. Parts of it contradict other parts of it

I spent a lot of time just moving equipment and changing settings, talked with ACI quite a bit on it as well.
If I lived in California, I would probably try to get on the payroll

More then happy to help!

 

[bobthethcguy]

I run my ACI intake and exhaust at a constant speed of 2, my intake is smaller then my exhaust so negative pressure stays in the tent.
I have an advanced Automation set at 78 degrees with a 2 degree transition. Meaning my fans will run at speed 2 and when temp hits 78 goes up to speed 3 and every 2 degrees higher in temp it gets, the fans go up another speed.

Do you have a humidifier? Do you run it inside or outside the tent?
I feel humidifiers (at least with an intake fan on tent) work better when outside tent and directed so the mist goes through the intake fan, then all the air coming into the tent will be with mist from the humidifier.
Seems to keep the tent more consistent and don't lose as much humidity because it's in all of the intake air.

Most of us have never supplemented co2 or even measured it for that matter, sure it has it's benefits but with a sealed room and a very powerful light. Need to be able to run a high ppfd with co2 supplementation.

I have the T3 Humidifier and the Thermoforge (I keep my house at 62f during the winter, I like cold). Humidifier is in the tent, I had the unit outside the tent with the hose directed to a side top hole, but I kept reading how the condensation will still form and drip back down the hose into the area that says don't let water enter here...then it breaks the unit. I did do a week long test run with it out of the tent and then in and it def felt more stable in the tent, but I never tried actually directing it through the intake fan.

My current settings by Port #:

1. Intake Fan (AUTO)
   1. Temp Trigger High 78f
   2. Humidity Trigger High 70%
2. Exhaust Fan (AUTO)
   1. Temp Trigger High 78f
   2. Humidity Trigger High 70%
3. Light (ON)
   1. Set to Lvl3 as I'm in second week of Seedling
4. Heat (AUTO)
   1. Temp Trigger Low 75f
5. Humidifier (AUTO)
   1. Humidity Trigger Low 68%
6. Osc Fan (CYCLE)
   1. 15m ON/15m OFF
7. Osc Fan (CYCLE)
   1. 15m ON/15m OFF
8. Empty

My goal is to keep environment within seedling range of 70-80f and 60-70% RH for a VPD of .6-1.1kpa, current setup is keeping the system around .85 kpa with a Leaf Temp Offset of -2f (Taken via the ACI temp gun thing)

My environment outside the tent is a 5x7 bathroom with a closed door. It's about 70f and 45-50% humidity. Intake fan is on floor and feeds to bottom hole in sidewall of tent. Exhaust fan is mounted to wall near tent and pulls from top panel hole in tent, carbon filter inside tent in corner, the exhausted goes to outside through a window. (Pic below)

In reality it's the only room in the house I can place the tent due to 8 cats and electrical considerations, that bathroom is the newest and has a newer circuit, my office is close by and has a door but all my servers kill that circuit, had to decom one just to run the AC to cool that space more.

how/where are you set up? closet? bedroom? etc. are you, or can you set up a "lung room"? that is what i'll be doing

My tent is in a tiny bathroom, a 3x3 tent. My house was built in 1840 and has a dirt floor basement, it was way to wet down there to attempt any sort of setup, even running a dehumidifier didn't help much, my gfs stepdad is a Navy Seabee and cautioned me on trying to go too dry in a house this old, something about house needs to breathe and the older houses don't need to be sealed like new ones. I even still have the original horse hair lathe/plaster.

 

[Newty]

What do you have your buffer settings at for your humidifier and heater?
The heater is going to take away from humidity also.
What are your buffer or transition settings for your exhaust and intake?

I run a T3 Humidifier also run a Thermoforge.
With how small the room the tent is in, keep the door closed and use the humidifier inside the little room (outside your tent) without the hose, use the regular cap instead.
If you can get the RH up in the little room the tent is in, the tent will be fed humidifier air.

Like I said before, you shouldn't have temp and humidity triggers on the same port/piece of equipment. 1 trigger per piece of equipment.

 

[bobthethcguy]

What do you have your buffer settings at for your humidifier and heater?
The heater is going to take away from humidity also.
What are your buffer or transition settings for your exhaust and intake?

I run a T3 Humidifier also run a Thermoforge.
With how small the room the tent is in, keep the door closed and use the humidifier inside the little room (outside your tent) without the hose, use the regular cap instead.
If you can get the RH up in the little room the tent is in, the tent will be fed humidifier air.

Like I said before, you shouldn't have temp and humidity triggers on the same port/piece of equipment. 1 trigger per piece of equipment.

My current settings by Port #:

1. Intake Fan (AUTO)
   1. Temp Trigger High 78f
   2. Humidity Trigger High 70%
   3. Trans 2f/2%
   4. Min 0/Max 1
2. Exhaust Fan (AUTO)
   1. Temp Trigger High 78f
   2. Humidity Trigger High 70%
   3. Trans 2f/2%
   4. Min 0/Max 1
3. Light (ON)
   1. Set to Lvl3 as I'm in second week of Seedling
4. Heat (AUTO)
   1. Temp Trigger Low 75f
   2. Min 0/Max 6
   3. No Trans/Buffer
5. Humidifier (AUTO)
   1. Humidity Trigger Low 68%
   2. Trans 1f/1%
   3. Min 0/Max 6
6. Osc Fan (CYCLE)
   1. 15m ON/15m OFF
7. Osc Fan (CYCLE)
   1. 15m ON/15m OFF
8. Empty

 

[PooToe]

So if I'm understanding this correctly, when your exhaust fan goes on it cools the tent out of range or does the humidity go out of range?

 

[bobthethcguy]

So if I'm understanding this correctly, when your exhaust fan goes on it cools the tent out of range or does the humidity go out of range?

When I/E fans come on the Temp drops from the stable 75-77 range to 68f and Humidity drops drastically from 70% to 50%. I got my setup to Cycle the Intake/Exhaust, 1 min ON, 1 hour OFF. After the min run time the system stabilizes again fairly quickly.

What do you have your buffer settings at for your humidifier and heater?
The heater is going to take away from humidity also.
What are your buffer or transition settings for your exhaust and intake?

I run a T3 Humidifier also run a Thermoforge.
With how small the room the tent is in, keep the door closed and use the humidifier inside the little room (outside your tent) without the hose, use the regular cap instead.
If you can get the RH up in the little room the tent is in, the tent will be fed humidifier air.

Like I said before, you shouldn't have temp and humidity triggers on the same port/piece of equipment. 1 trigger per piece of equipment.

I'm going to test your idea, being that the bathroom in question is newer it may be sealed a little better and be able to hold a good level

 

[PooToe]

So the tent sits in a lung room. Close the A/C vent in the room and see if the room warms up. Higher air temp in the lung room will warm the tent also. You can heat the lung room to whatever temp you want in your tent but still have your exhaust fan running. This will allow good air exchanges in the tent that you want happening.

Humidity at 50% is good. If you can get the air temps up in the lung room to help the LED lighting heat get you in range then you should be golden.

Some people remove their LED's and use HID lighting for the added warmth. Usually basement growers.

You said that when your fans are off your temps stabilize at 75° - 77° but drop to 68° when your fans come on. What speed are the fans at when this happens?

I would first set your fan speed at a constant speed. Calculate the amount of CFM you need to do an air exchange every 5 minutes in your tent or room. Essentially 12 exchanges an hour. Set your speed to be able to exhaust the calculated CFM. Your temps should drop.
Have a heater in the lung room and set it to whatever temperature you feel will stabilize the tent at 77°. Hopefully, shutting the A/C vent should be sufficient but if not, there are a lot of inexpensive mini heaters with thermostats on Amazon that can do the job cheaply.

Now you can schedule your fan to run at the speed you calculated when lights go on and can both stabilize your temp and humidity and still get the air exchanges you want in the tent.

Also, now that you have a constantly running exhaust fan you won't need an intake fan.

You can also try exhausting back into the lung room but stabilizing your specs will be harder this way.

 

[FrenchKiss]

Doing yoga in my grow room will set off the alarm on my CO2 monitor.

Lol