exhaust air at night in Sealed Room?

[TheyCallMeJJay]

There's nothing wrong with venting at lights out. The cost is peanuts to get your C02 up to levels once the lights come on.

C02 levels at lights off is useless. If I could I would supplement with Oxygen at night I would, and come to think of it I might look into it.

Anyone who's done this for any amount of time knows dam well that the extra cost is worth whatever motivates you. In some cases, its safety of knowing you're scrubbing the smell and the air. Again, its peanuts when you're at 5,000% profit or whatever lol

 

[TheyCallMeJJay]

Seriously, what harm can come from exchanging air at all times? Other than cost?

 

[moses wellfleet]

Seriously, what harm can come from exchanging air at all times? Other than cost?

I think the OP's question has been answered already

So if you would post the above question in this thread https://www.icmag.com/ic/showthread.php?t=260794

I will be happy to discuss it with you there, hopefully shredGnar will swing by too!

 

[EclipseFour20]

This doesn't make any sense..

You also say you like free 400 ppm co2, but you run 1200 ppm bottled. How can you exhaust while running bottled co2?

You also say you close the exhaust to save your co2, but in your first paragraph you say you run exhaust at night when the lights are on..

The fact that you don't need to use your a/c during the winter is negligible considering the production increase
Gained by the plants. My extra yield pays for the extra electricity used by the a/c ten fold (probably more).

You do not have a "closed environment"with an exhaust fan..period. When you exchange air it is the opposite.

Can I see some quotes from your "air handling experts" who commented on exhausting grow rooms?

I can't believe that it would be better to exhaust all my conditioned air to draw in air from inside with god knows what kind of mold and mildew or whatever other Shit is floating around.

I wouldn't call ambient air "free co2"since it is not I'm the ppm range for maximum growth. To see any gain the ppms need to be higher then the ambient air. The whole reason I spent all the money on equipment so I don't have to deal with fans and ducting and less yields.

Not only are you drawing out your co2 but your drawing out your humidity and other parameters that I work hard to achieve. By using exhaust your grow room is affected by outside factors such as temp and humidity. My room can be set for the perfect growth parameters any time of the year unaffected by outside conditions.

Point being you absolutely do not need any air exchange if you have the proper equipment.


Seems to me you are passing your misconceptions as facts because you misunderstand sealed rooms.

I agree, the way you put it...it makes zero sense. So lets correct your incorrect assumptions/statements so we can look at what is "real" and ignore the "fiction".

First, let's make it simple, my flowering time is 9PM-9AM (during the night). I have fans that draw outside air into my grow chamber, at nighttime/early morning outside temperatures range as low as 32 degrees in the winter (I live near the ocean) and in the low 60s during the summer (maybe during the year there might be 10 warm nights when the temps will be the 70s and another 10 cold nights when the temps are at or below freezing.

Re: CO2. When the lights are on my goal is to have 1500 ppm. Since the outside air (ambient) provides around 500 ppm, then my bottled CO2 must provide the other 1000 ppm, for a total of 1500 (500 + 1000). When the lights are on, outside air is drawn into the grow chamber and the exhaust ducting (electric damper) is closed providing the grow chamber with positive air pressure. Without bottled CO2, the grow chamber's CO2 measured in the 400-600 ppm range (I called it 500). I measured the CO2 right outside the grow chamber (inside a closed garage), and it barely peaked at 100 ppm...basically zero.

Re: Exhaust. The exhaust ducting terminates in my attic which is also the location for the exhaust fan and electric damper setup (I pull the exhaust air from the grow chamber). When the exhaust fan is on, the electric damper also opens allowing air from my grow chamber to exhaust into the attic. When the fan is off, the electric damper is closed--preventing any air movement in or out the exhaust ducting. Closed environment.

Re: Air Exchange. When the lights are off (9AM-9PM) I have a timer set (three times for half hour each...total 1.5 hours) to turn on the exhaust fan and open the electric damper. Each day the grow chamber has the equivalent of around "30 air changes" while the lights are off.

Re: AC. I definitely use an AC and my temps range 75-77 degrees inside the grow chamber; the AC is set to the "energy saver" mode, meaning if the room is cool enough the AC cycles off...if the room is warm the AC cycles. My point is--with the constant flow of cold night/early morning air blowing into the grow chamber...the AC does not need to work as much (cooler room). During winter (like now) the AC seldom cycles on at all when the lights are on, in fact the air can dip to 73-75 degree range...without the AC on. During the rest of the year, the AC is on about half the time (1/2 hour for each hour).

Re: Air cooled lamps. I also pull cold outside air through the lamp hoods in such a way each lamp receives cool air--not warm air from two lamps daisy chained together. When the lights are on the lamp hoods are cool to the touch, not warm, not hot...just cool. Thus I do not have warm lamp hoods warming the air in the grow chamber.

Re: Air purification. I have the big CAN150 filter attached to 14" fan suspended from the ceiling (above the lights) that functions as an air scrubber...and is on 24/7. So I have the best of both worlds: Bad air components are "scrubbed" through the CAN150 filter as well as being diluted with "fresh air".

As to me passing "misconceptions as facts because (I) misunderstand sealed rooms".....I submit that is either a premature conclusion on your behalf or a very tall tale you made up without any basis.

 

[jd4083]

I'm confused. Do you or do you not run a sealed room?

 

[EclipseFour20]

I'm confused. Do you or do you not run a sealed room?

When lights are on...no air leaves the room.
When lights are off...air leaves the room 3 times for 1/2 hours each.
When lights are on....fresh air enters the room.
When lights are off...fresh air enters the room and is exhausted out 3 times for 1/2 hours each--other than that, no air enters or leaves the room.

It is a sealed room when I want it to be.

 

[TheyCallMeJJay]

Re: CO2. When the lights are on my goal is to have 1500 ppm. Since the outside air (ambient) provides around 500 ppm,

I've been calibrating my Co2 meter around 380 ppm. I'm curious as to where you get this 500 ppm number as I think the planet collapses at that.

I could be wrong. Which is practically all the time

 

[TheyCallMeJJay]

When lights are on...no air leaves the room.
When lights are off...air leaves the room 3 times for 1/2 hours each.
When lights are on....fresh air enters the room.
When lights are off...fresh air enters the room and is exhausted out 3 times for 1/2 hours each--other than that, no air enters or leaves the room.

It is a sealed room when I want it to be.

Sounds like you and I have the same options built in. Which is nice.

 

[EclipseFour20]

I've been calibrating my Co2 meter around 380 ppm. I'm curious as to where you get this 500 ppm number as I think the planet collapses at that.

I could be wrong. Which is practically all the time

I had plants in the room, outside air on, AC on and after 11 hours of lights on I measured the CO2 (air tubes) 3 times...each time drawing air from different points in the room.

Same process to measure how much bottled CO2 to add.

 

[shredGnar]

I agree, the way you put it...it makes zero sense. So lets correct your incorrect assumptions/statements so we can look at what is "real" and ignore the "fiction".

First, let's make it simple, my flowering time is 9PM-9AM (during the night). I have fans that draw outside air into my grow chamber, at nighttime/early morning outside temperatures range as low as 32 degrees in the winter (I live near the ocean) and in the low 60s during the summer (maybe during the year there might be 10 warm nights when the temps will be the 70s and another 10 cold nights when the temps are at or below freezing.

Re: CO2. When the lights are on my goal is to have 1500 ppm. Since the outside air (ambient) provides around 500 ppm, then my bottled CO2 must provide the other 1000 ppm, for a total of 1500 (500 + 1000). When the lights are on, outside air is drawn into the grow chamber and the exhaust ducting (electric damper) is closed providing the grow chamber with positive air pressure. Without bottled CO2, the grow chamber's CO2 measured in the 400-600 ppm range (I called it 500). I measured the CO2 right outside the grow chamber (inside a closed garage), and it barely peaked at 100 ppm...basically zero.

Re: Exhaust. The exhaust ducting terminates in my attic which is also the location for the exhaust fan and electric damper setup (I pull the exhaust air from the grow chamber). When the exhaust fan is on, the electric damper also opens allowing air from my grow chamber to exhaust into the attic. When the fan is off, the electric damper is closed--preventing any air movement in or out the exhaust ducting. Closed environment.

Re: Air Exchange. When the lights are off (9AM-9PM) I have a timer set (three times for half hour each...total 1.5 hours) to turn on the exhaust fan and open the electric damper. Each day the grow chamber has the equivalent of around "30 air changes" while the lights are off.

Re: AC. I definitely use an AC and my temps range 75-77 degrees inside the grow chamber; the AC is set to the "energy saver" mode, meaning if the room is cool enough the AC cycles off...if the room is warm the AC cycles. My point is--with the constant flow of cold night/early morning air blowing into the grow chamber...the AC does not need to work as much (cooler room). During winter (like now) the AC seldom cycles on at all when the lights are on, in fact the air can dip to 73-75 degree range...without the AC on. During the rest of the year, the AC is on about half the time (1/2 hour for each hour).

Re: Air cooled lamps. I also pull cold outside air through the lamp hoods in such a way each lamp receives cool air--not warm air from two lamps daisy chained together. When the lights are on the lamp hoods are cool to the touch, not warm, not hot...just cool. Thus I do not have warm lamp hoods warming the air in the grow chamber.

Re: Air purification. I have the big CAN150 filter attached to 14" fan suspended from the ceiling (above the lights) that functions as an air scrubber...and is on 24/7. So I have the best of both worlds: Bad air components are "scrubbed" through the CAN150 filter as well as being diluted with "fresh air".

As to me passing "misconceptions as facts because (I) misunderstand sealed rooms".....I submit that is either a premature conclusion on your behalf or a very tall tale you made up without any basis.

I still disagree with you bro..

Even with your exhaust closed, when you are pushing ambient air into your room and causing positive pressure you are pushing out your co2 enriched air through whatever cracks there are in your room, regardless of how sealed you think it is.

If you have a 1500 ppm room and are mixing in 500 ppm air, you aren't adding co2 you are diluting your enriched air with less dense levels of co2.. In turn blowing out your enriched co2 levels.

I am in the Rockies..where it is below 32 Pretty much half the year and my a/c runs about the same year around because my room is unaffected by outside conditions. This is desirable, in my opinion, as I have total control of environment and have it consistent day in and day out which, in my opinion, is one of the most important factors for optimal growth I.e yield

You also insist that air bring brought from outside of your room is fresh.. is it coming from outside? Air inside a house is usually very dirty. I don't know why you would go through the trouble if scrubbing your air clean just to dump it outside drawing in the unknowns.



Also..I tend to get better growth around 1000ppm vs 1500. 82-85 * f. They are always much perkier and reach towards the lights with the higher temps!

 

[shredGnar]

I agree, the way you put it...it makes zero sense. So lets correct your incorrect assumptions/statements so we can look at what is "real" and ignore the "fiction".

First, let's make it simple, my flowering time is 9PM-9AM (during the night). I have fans that draw outside air into my grow chamber, at nighttime/early morning outside temperatures range as low as 32 degrees in the winter (I live near the ocean) and in the low 60s during the summer (maybe during the year there might be 10 warm nights when the temps will be the 70s and another 10 cold nights when the temps are at or below freezing.

When the lights are on, outside air is drawn into the grow chamber and the exhaust ducting (electric damper) is closed providing the grow chamber with positive air pressure. Without bottled CO2, the grow chamber's CO2 measured in the 400-600 ppm range (I called it 500). I measured the CO2 right outside the grow chamber (inside a closed garage), and it barely peaked at 100 ppm...basically zero.

Re: Exhaust. The exhaust ducting terminates in my attic which is also the location for the exhaust fan and electric damper setup (I pull the exhaust air from the grow chamber). When the exhaust fan is on, the electric damper also opens allowing air from my grow chamber to exhaust into the attic. When the fan is off, the electric damper is closed--preventing any air movement in or out the exhaust ducting. Closed environment

And for the record; if you have a fan pushing air into your grow while lights are on, regardless of exhaust, it is not a sealed room.

Do you use a co2 meter? I'm curious how you landed on these numbers when you measures your levels..

 

[shredGnar]

There's nothing wrong with venting at lights out. The cost is peanuts to get your C02 up to levels once the lights come on.

C02 levels at lights off is useless. If I could I would supplement with Oxygen at night I would, and come to think of it I might look into it.

Anyone who's done this for any amount of time knows dam well that the extra cost is worth whatever motivates you. In some cases, its safety of knowing you're scrubbing the smell and the air. Again, its peanuts when you're at 5,000% profit or whatever lol

It isn't peanuts.. My tanks lasted nothing when I used to vent my expensively conditioned and enriched air out to space when the lights turned off..

Not to mention you are exhausting your stank all over the place and in turn drawing in potentially harmful pests or spores.


I'm sharing my experience with the OP.. if you have the proper equipment there is no need to exhaust, and in my opinion actually works against you in the attempt to make a perfect environment for your plants.

 

[TheyCallMeJJay]

It isn't peanuts.. My tanks lasted nothing when I used to vent my expensively conditioned and enriched air out to space when the lights turned off..

Not to mention you are exhausting your stank all over the place and in turn drawing in potentially harmful pests or spores.


I'm sharing my experience with the OP.. if you have the proper equipment there is no need to exhaust, and in my opinion actually works against you in the attempt to make a perfect environment for your plants.

I'm sharing my experience as well with the OP.

It's peanuts. Don't hyperbole it. Give me your space, and cost and I can calculate it. I'm sure you can as well.

Obviously we would filter our stank.

I think we should be aware that we're dealing with 3 gasses. All three have different atomic weights in corresponding volumes. Anything above atmospheric pressure will leak out. Positive pressure is a killer. Think about it, you're introducing a gas and the volume will leak at atmosphere. No one has a truly sealed room. Unless its a welded steel room. I'm always amazed at the confidence of people who don't filter. As a non smoker, I can tell.

 

[TheyCallMeJJay]

I'm sure the next question is whether I have a sealed room. The answer is yes. I can produce a vacuum when my burner is not running.

 

[shredGnar]

I'm sharing my experience as well with the OP.

It's peanuts. Don't hyperbole it. Give me your space, and cost and I can calculate it. I'm sure you can as well.

Obviously we would filter our stank.

I think we should be aware that we're dealing with 3 gasses. All three have different atomic weights in corresponding volumes. Anything above atmospheric pressure will leak out. Positive pressure is a killer. Think about it, you're introducing a gas and the volume will leak at atmosphere. No one has a truly sealed room. Unless its a welded steel room. I'm always amazed at the confidence of people who don't filter. As a non smoker, I can tell.

My tanks used to last 4 days when I ran exhaust at night.. now they last a full week. I live in the mountains and the only co2 supplier charges $30 per exchange. You're right that it isn't gong to break the bank..but I found that getting rid of the extractor fan I saved on co2 not to mention the annoying fan and ducting, less trips to the hydro store etc.

And you're also right that my room isn't perfectly sealed, I use it more as an industry term. And my very slight positive pressure from co2 being injected is different from an intake fan in that I'm adding a higher gradient of co2 ppms and expelling lesser amounts.

Also I do filter.. constantly inside my (almost) sealed grow room where the odors only escape when I open the door.

But I am legal and in the weed growing part of town so smell isn't a huge deal for me.

Do what makes you feel best... I am sharing what I believe is the best way, after trying many other methods.

 

[shredGnar]

And also yes plants need oxygen, is nitrogen the third gas you're referring to?

Anyway atmosphere is approx. 21% o2 and not even .05% is co2.. triple that concentration and you've got .15% co2. Still more than enough o2 for plants.

You don't have exhaust fans in your home do you? But I'm guessing you breathe okay..

 

[EclipseFour20]

I still disagree with you bro..

Even with your exhaust closed, when you are pushing ambient air into your room and causing positive pressure you are pushing out your co2 enriched air through whatever cracks there are in your room, regardless of how sealed you think it is.

If you have a 1500 ppm room and are mixing in 500 ppm air, you aren't adding co2 you are diluting your enriched air with less dense levels of co2.. In turn blowing out your enriched co2 levels.

I am in the Rockies..where it is below 32 Pretty much half the year and my a/c runs about the same year around because my room is unaffected by outside conditions. This is desirable, in my opinion, as I have total control of environment and have it consistent day in and day out which, in my opinion, is one of the most important factors for optimal growth I.e yield

You also insist that air bring brought from outside of your room is fresh.. is it coming from outside? Air inside a house is usually very dirty. I don't know why you would go through the trouble if scrubbing your air clean just to dump it outside drawing in the unknowns.



Also..I tend to get better growth around 1000ppm vs 1500. 82-85 * f. They are always much perkier and reach towards the lights with the higher temps!

You are entitled to have your own definition of "sealed room"--but in the professional world, majority of green houses/grow chambers have fresh air supply for both CO2 and plant health..especially if there is a CO2 generator.

What little CO2 slips through the cracks and crevices is rather minor (a cost I am willing to bear) as the grow chamber is designed to have "positive air pressure". With "negative air pressure" the grow chamber behaves like a vacuum and sucks in all kinds of dirt, hair, bugs, critters, etc. At $10/tank to refill, I can handle the little loss of CO2 I experience.

Yes....the air I bring in is fresh, cool night/morning air drawn from vents under my roof eave. Hence the reason why my AC is not working as hard...duh!

BTW...what amazes me is--how someone that knows so much, can judge/critique something they have never seen.....nor fully understand.

 

[shredGnar]

You are entitled to have your own definition of "sealed room"--but in the professional world, majority of green houses/grow chambers have fresh air supply for both CO2 and plant health..especially if there is a CO2 generator.

What little CO2 slips through the cracks and crevices is rather minor (a cost I am willing to bear) as the grow chamber is designed to have "positive air pressure". With "negative air pressure" the grow chamber behaves like a vacuum and sucks in all kinds of dirt, hair, bugs, critters, etc. At $10/tank to refill, I can handle the little loss of CO2 I experience.

Yes....the air I bring in is fresh, cool night/morning air drawn from vents under my roof eave. Hence the reason why my AC is not working as hard...duh!

BTW...what amazes me is--how someone that knows so much, can judge/critique something they have never seen.....nor fully understand.

not sure what the point of flinging barbs is.. but I'm quite sure you are the one who is misunderstanding the concept of a sealed room.

I am not speaking of greenhouses, I am referring to indoor growing. I've been to many decent sized grows and run two humble grows as well.. no one that has a sealed room runs an intake fan while they are supplementing co2. Some exhaust at night, which I also do not think is necessary, in my opinion.

From what you are saying you have an intake fan blowing in ambient air at all times, yet refer to it as sealed.

Also, from your words it sounds like you are saying if you add 1000 ppm of co2, then add ambient air containing 500 ppm you then have 1500 ppm. I think you need to re address that logic..
Correct me if I am misunderstanding you

Do you have a constant meter telling you the co2 ppm of your room?

 

[shredGnar]

Also I never have claimed to know so much, I am sharing my experiences with the op and whoever else cares enough to read..

I am only critiquing what you have shared with me, i never meant to insult your knowledge or setup.. I am trying to lay, what I believe to be, misconceptions to rest!

 

[EclipseFour20]

Dude, I respect your opinion, now why not try respecting others (mine). Let me guess, you think a sealed room means "nothing in and nothing out"...right? Stagnant air that is never diluted with fresh air...right?