exhaust air at night in Sealed Room?

[shredGnar]

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?

I suppose I would consider it semi sealed if you exhausted at night. You can control ppm humidity etc up or down with lights on..

However if you are drawing in ambient air into the grow area all the time I, and I believe most other indoor growers, would not consider this to be sealed.. I don't see how it could be considered sealed.

I guess the size of the fan drawing in has a big impact..

But, regardless of exhaust, if you have a fan blowing in x amount of CFM, that air has to be displaced out of the room. The fan probably does lose some volume since the room is slightly pressurized..

Anyway you are still blowing in a lower level of co2 to a higher gradient this diluting your levels inside the room.

If you mix a fixed amount of 1000 ppm co2 enriched air, with an equal amount of 500 ppm air you and up with 750 ppms co2, effectively lowering your ppms.

And bro..the air is not stagnant. That is exactly the misconception...

Lights on my meter and regulator maintain 1000 ppm of co2, giving them lots of co2 for photosynthesis.. much more than ambient air can ever provide increasing metabolism rates..

When lights turn off the meter stops adding co2, plants dump their co2 and the levels usually rise to 1200 ppm..

Even though this is triple the number of ambient air there is still approx. 200 times the amount of oxygen than carbon dioxide in the air.. more than enough for the plants! All during lights on they make oxygen..

Air is constantly scrubbed and either humidified or dehumidified (I think I just made both those words up)
Depending on what point of the cycle I am in or if lights are on or off...

No ambient air need enter to mess up my awesome parameters, rain shine sleet snow my room is where I see it at

You say your room is at 73 ish degrees in the winter, because the temp is subject to outside conditions with the intake. This is too cold I'm my opinion for optimal temps! This is why I like totally sealed.. I have total control of the parameters which, in my opinion, is a big deal.

Not saying your way is wrong man, I just think air exchange isn't conducive to a perfect environment. I think this because I used to do it just like you! I was talked into it and never looked back..

 

[TheArchitect]

I'm confused about the concept of stagnant air.

Stagnant means no flow, or still. So it not really the correct term, though I do think I get the point.

First, you still scrub the air with carbon and particulate filtration, so dust and odors/voc's are eliminated, second you still use fans to circulate air in the room, that eliminates the issue of stagnant air, and third the stochiometric ratio of co2->o2 production in photosynthesis is 1:1, meaning every molecule of co2 consumed by the plants is converted to o2.

The biggest concern is humidity, which just requires the right equipment.

 

[shredGnar]

I'm confused about the concept of stagnant air.

Stagnant means no flow, or still. So it not really the correct term, though I do think I get the point.

First, you still scrub the air with carbon and particulate filtration, so dust and odors/voc's are eliminated, second you still use fans to circulate air in the room, that eliminates the issue of stagnant air, and third the stochiometric ratio of co2->o2 production in photosynthesis is 1:1, meaning every molecule of co2 consumed by the plants is converted to o2.

The biggest concern is humidity, which just requires the right equipment.

Boom..truth

 

[shredGnar]

lol, same here. I find I work in there so often plants get all the CO2 they need from my breathing. When I did try CO2 enrichment in veg, plants went crazy and growth was way too quick!

That I will have to try...sounds fun! Haha

 

[Crumpledtrumpet]

What is your CO2 source, propane burner or bottled?

Hi moses wellfleet, I have no co2 source, propane burner or bottled, All i have is low air exchange at lights out.

 

[TheyCallMeJJay]

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

A red herring statement. It's funny though, and reminds me of the Germans insatiable appetite for fresh air. You'll be walking around town and notice windows open randomly everywhere.

Those healthy Germans. What they're doing is exchanging the Co2 in order to maintain health and gain energy. They do this all the time. They have a saying and its Germans need fresh air, Americans need air fresheners.

 

[TheyCallMeJJay]

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.

And this is exactly what I think gets missed when discussing sealed rooms. The vast majority of growers are in fact not legal. More often than not they get accustomed to the smell and don't notice it.

Unfortunately, other people do notice it. And that's a major problem.

 

[EclipseFour20]

Shred,

Let me say it this way...if professional grow chambers have fresh air intake and exhaust (air exchange) capabilities, what do they know that you don't?

Some features of "Professional Grow Chambers"--

Airflow
Uniform airflow is introduced to the growth area through
Meditech’s patented Uni-floor which produces a precise
volume of air, directed upward through the plant
material. Filtered and adjustable fresh air intake and
exhaust openings enable researchers to exchange air to
the chamber in a controlled manner.

Source: newmeditech.com/secure/wp-content/uploads/2013/01/Plant-Growth-Chamber-ME7-2.pdf

Airflow
Airflow for the PGW36 is distributed uniformly upward using
Conviron’s innovative Unifloor® air distribution plenum. The unit
includes fresh air intake and exhaust ports which are adjustable to
allow up to 55 ft3/min (1.55m3/min.) of air exchange.

Source: www.thermofisher.co.nz/Uploads/file/Environmental-Industrial/Environmental-Monitoring-Safety/Environmental-Simulation/Plant-Growth-Chambers-Rooms/Conviron/pdf/PGW36-Walk-In-Plant-Growth-Room.pdf

Airflow system
Uniform airflow and climat is introduced to the internal growing area in a horizontal airflow pattern, discharged
from a perforated special designed rear wall plenum. The air travels along the entire rear wall, over the shelves and
returns via the door side back downwards over the build in climate system.
The airflow speed is very low to prevent dehydration of the plants or the soil and also prevent stress to the plants
due to high airspeeds.
The airspeed also has been optimized to realize a very good and stable homogenized climate in the chamber.
Using special ventilators results in a extreme low noise cabinet.
On the back of the cabinet an adjustable fresh air intake port has been mounted to allow fresh air to enter the cabinet interior.

Source: hettichbenelux.com/content/downloads/Hettich%20ESP%20Climate%20chambers%20for%20plant%20growth%20-%20English.pdf

Hmmm...I guess since these grow chambers have "fresh air intake", they would not be considered "sealed"...right?

Sorry, I defer to those that know what they are doing (professionals)--over "stoner logic" or "bro-science".

BTW...my electric bill dwarfs my CO2 bill by several factors, so IMHO one is "penny wise and pound foolish" if the focus of frugality is on CO2 ($) while ignoring the cost of electricity ($$$$$$$$$$$$$$). In other words, a $100 decrease in electricity (less AC due to outside fresh air inflow) certainly outweighs the extra cost of CO2 (what $1 maybe 2 for the extra CO2?...I pay $10/tank). Pay $2 and save $100....I will do that all day (assuming no degradation in quality/quantity).

 

[JointOperation]

how easy is it to run a sealed room with Gavitas?

 

[TheArchitect]

None of those growth chambers come standard with co2, its an add on, so their base designs are around ventilating the chamber, with the option to seal it up with dampers to add co2, effectively sealing it. Nothing in the brochures talks about ventilation being designed into the chamber for the purpose of exhausting co2.

 

[EclipseFour20]

None of those growth chambers come standard with co2, its an add on, so their base designs are around ventilating the chamber, with the option to seal it up with dampers to add co2, effectively sealing it. Nothing in the brochures talks about ventilation being designed into the chamber for the purpose of exhausting co2.

Exhausting CO2? Who is talking about that, don't plants take up CO2 and convert it? I think the issue at hand is "air exchange" and "fresh air supply", and if they disqualify a grow environment from being classified as "sealed environment". That said...when I designed my "grow chamber" I looked at the designs of both greenhouse and "sealed environments" and incorporated the best designs of what I saw and folded in my cultivating/horticulture methodology (which is to adopt the best practices from all growing disciplines and ignore what does not apply/make sense). Much has been written about plant health and the benefits of fresh air...so rather that spout what happens to plant stomata at night and levels of CO2 consumed (or not)...let's save that minutia shit for another thread.

But if we agree there are different degrees of "controlled" sealed environments, including the camp that believes "nothing in nothing out...24/7" and the camp that believes "air exchange....when lights off"--what we are discussing really has nothing about room design, rather it has everything to do about cultivating practice. Both camps have air tight structures, temperature and humidity controls, supplement CO2, lights, odor abatement, etc...

IMHO, so far the only valid argument against having any "air exchange" is the depletion of CO2 and the cost to replenish it. After one considers the benefits of piping in cool night air in a warm environment (resulting in less AC use...less electricity) and weighing the cost to replenish CO2...I decided to save a few thousand a year and "waste CO2"--and enjoy healthy plants (fresh air every day...and complete air exchange equivalent to 30x room size each "night")

Seldom does "one size fit all".

 

[TheArchitect]

Maybe I didn't make my point clear.

Those growth chambers are built for constant air exchange, they are not sealed.

As an option you can add dampers and co2 equipment, in effect, sealing the room.

Nowhere in the brochure does it mention exhaust at night, though they obviously have that ability.




So supposing all else is equal, I'd rather maintain the controlled environment, and not introduce contaminates from outside.

Yes, plants dump co2 at night, so have your co2gen on a timer so it can't be triggered for an hour or two before lights out, the plants bring co2 down to ambient before the lights go out.

Dumping the stank from a 20kw grow is pretty risky as it just becomes extremely difficult to eliminate it all, and that's a major breach of op-sec.

As for increased electrical cost, I'll deal with it as its minor, I'd be using massive dehumidification wether or not the room was sealed.

I'd rather pay an extra couple hundred per run in electric than risk introduction of contaminated outside air, breaching op-sec, or losing pounds to mold because I didn't buy and run the correct equipment (proper sized dehumidifier(s))

 

[EclipseFour20]

Arch, your are right these chambers are not "gas tight". But since the joints are silicon sealed, doors with gasket seals, etc.... I speculate that if we compared them to the "sealed" grow rooms you are referring to, these professional growth chambers are more "sealed" than grow rooms.

But since my air flow (in and out) is controlled, I consider my environment "sealed"--since very little air escapes (cracks, crevices, opening door, etc). But all is good....I say TOE-mato you say TAH -mato.

Since I filter my incoming air I have zero fear of bringing any contamination into my grow chamber...lol, in fact I run the operation like a "clean room". Designated shoes that have never seen outdoors, fresh clothes, clean, clean, clean workspace, etc...that kind of "clean room" clean. Even the floors, walls and ceilings of the grow chamber are painted white (and repainted every year or so). Compulsive disorder? Borderline....lol.

 

[moses wellfleet]

Maybe I didn't make my point clear.

Those growth chambers are built for constant air exchange, they are not sealed.

As an option you can add dampers and co2 equipment, in effect, sealing the room.

Nowhere in the brochure does it mention exhaust at night, though they obviously have that ability.




So supposing all else is equal, I'd rather maintain the controlled environment, and not introduce contaminates from outside.

Yes, plants dump co2 at night, so have your co2gen on a timer so it can't be triggered for an hour or two before lights out, the plants bring co2 down to ambient before the lights go out.

Dumping the stank from a 20kw grow is pretty risky as it just becomes extremely difficult to eliminate it all, and that's a major breach of op-sec.

As for increased electrical cost, I'll deal with it as its minor, I'd be using massive dehumidification wether or not the room was sealed.

I'd rather pay an extra couple hundred per run in electric than risk introduction of contaminated outside air, breaching op-sec, or losing pounds to mold because I didn't buy and run the correct equipment (proper sized dehumidifier(s))

This... and you cannot rely on the weather to provide a constant source of ideal atmospheric conditions to pull through your rooms... once you exchange air with the outside you lose control!!!

 

[vostok]

A red herring statement. Germans need fresh air, Americans need air fresheners.

So very True ....lol!​

 

[TheArchitect]

Arch, your are right these chambers are not "gas tight". But since the joints are silicon sealed, doors with gasket seals, etc.... I speculate that if we compared them to the "sealed" grow rooms you are referring to, these professional growth chambers are more "sealed" than grow rooms.

But since my air flow (in and out) is controlled, I consider my environment "sealed"--since very little air escapes (cracks, crevices, opening door, etc). But all is good....I say TOE-mato you say TAH -mato.

Since I filter my incoming air I have zero fear of bringing any contamination into my grow chamber...lol, in fact I run the operation like a "clean room". Designated shoes that have never seen outdoors, fresh clothes, clean, clean, clean workspace, etc...that kind of "clean room" clean. Even the floors, walls and ceilings of the grow chamber are painted white (and repainted every year or so). Compulsive disorder? Borderline....lol.

I guess my point is a sealed room is sealed, meaning no outside air, whether that room is sealed well enough to hold pressure is irrelevant. If you build the room right, from the ground up, you'd be surprised how tight you can seal a room up though.

You can supplement a non sealed room by not running ventilation lights on, yes, but the room is 'sealed' lights on.

My bigger issue though is incoming air. Like moses pointed out, rarely is outside air ideal, even if your pulling it from inside a conditioned building. What happens during a rainy spring when humidity is high, dumping humid air from your room and bringing outside humid air is an exercise in futility.

I'm all in on sealed rooms on my next build out, check out the filtration I'll be running 24/7.http://www.abatement.com/air-purifier/learning-center-advanced-air-purification-technology.htm


http://www.abatement.com/pdf/cap600-1200-brochure-1109.pdf


I plan on building a shower and changing room, when you enter any plant room, first you shower, then change into freshly washed growroom dedicated clothing/shoes, anyone handling clones wears gloves and uses quat-am religiously, anyone entering flower chambers wears lintfree jumpers with hood, and beardnet if necessary.

 

[shredGnar]

Shred,

Let me say it this way...if professional grow chambers have fresh air intake and exhaust (air exchange) capabilities, what do they know that you don't?

Some features of "Professional Grow Chambers"--

Airflow
Uniform airflow is introduced to the growth area through
Meditech’s patented Uni-floor which produces a precise
volume of air, directed upward through the plant
material. Filtered and adjustable fresh air intake and
exhaust openings enable researchers to exchange air to
the chamber in a controlled manner.

Source: newmeditech.com/secure/wp-content/uploads/2013/01/Plant-Growth-Chamber-ME7-2.pdf

Airflow
Airflow for the PGW36 is distributed uniformly upward using
Conviron’s innovative Unifloor® air distribution plenum. The unit
includes fresh air intake and exhaust ports which are adjustable to
allow up to 55 ft3/min (1.55m3/min.) of air exchange.

Source: www.thermofisher.co.nz/Uploads/file/Environmental-Industrial/Environmental-Monitoring-Safety/Environmental-Simulation/Plant-Growth-Chambers-Rooms/Conviron/pdf/PGW36-Walk-In-Plant-Growth-Room.pdf

Airflow system
Uniform airflow and climat is introduced to the internal growing area in a horizontal airflow pattern, discharged
from a perforated special designed rear wall plenum. The air travels along the entire rear wall, over the shelves and
returns via the door side back downwards over the build in climate system.
The airflow speed is very low to prevent dehydration of the plants or the soil and also prevent stress to the plants
due to high airspeeds.
The airspeed also has been optimized to realize a very good and stable homogenized climate in the chamber.
Using special ventilators results in a extreme low noise cabinet.
On the back of the cabinet an adjustable fresh air intake port has been mounted to allow fresh air to enter the cabinet interior.

Source: hettichbenelux.com/content/downloads/Hettich%20ESP%20Climate%20chambers%20for%20plant%20growth%20-%20English.pdf

Hmmm...I guess since these grow chambers have "fresh air intake", they would not be considered "sealed"...right?

Sorry, I defer to those that know what they are doing (professionals)--over "stoner logic" or "bro-science".

BTW...my electric bill dwarfs my CO2 bill by several factors, so IMHO one is "penny wise and pound foolish" if the focus of frugality is on CO2 ($) while ignoring the cost of electricity ($$$$$$$$$$$$$$). In other words, a $100 decrease in electricity (less AC due to outside fresh air inflow) certainly outweighs the extra cost of CO2 (what $1 maybe 2 for the extra CO2?...I pay $10/tank). Pay $2 and save $100....I will do that all day (assuming no degradation in quality/quantity).

I can't tell if this is a serious rebuttal.

I didn't see any mention as to those being a sealed environment. How could they, they have airflow..

If your cared enough to read this thread all the info to debunk your argument is here..

Show me one respectable grow on any forum that documents their results and brings in fresh air 24/7 yet refers to it as sealed...

The wasted co2 i isn't the issue..it's that, as everyone else has mentioned, you do not have control of your grow room parameters.

For the 3rd time, do you have a constant ppm meter in your grow? I'd like to know what it says..

As the architect stated the few measly hundred dollars I would save on electricity from using outside air is a far cry from the gains I see having total control of my environment.

You can use your intake fan bro, nobody is mad at you... but you do not have a sealed room. It's the opposite.. If outside conditions have an affect on your grow, you are missing the point of a sealed room. By diluting your enriched air with ambient air your plants are not seeing the advantage! Do not understand how you are not realizing this...

Btw.... You are the one passing around stoner science with your claims of stagnant air.

Biology fact.. plants need o2 and co2 to function. If they supply their own o2 and I am supplying more dense levels of co2 than your inline fan, what else is needed?

You could say dehumidifier but I've got that as well..

 

[shredGnar]

I guess my point is a sealed room is sealed, meaning no outside air, whether that room is sealed well enough to hold pressure is irrelevant. If you build the room right, from the ground up, you'd be surprised how tight you can seal a room up though.

You can supplement a non sealed room by not running ventilation lights on, yes, but the room is 'sealed' lights on.

My bigger issue though is incoming air. Like moses pointed out, rarely is outside air ideal, even if your pulling it from inside a conditioned building. What happens during a rainy spring when humidity is high, dumping humid air from your room and bringing outside humid air is an exercise in futility.

I'm all in on sealed rooms on my next build out, check out the filtration I'll be running 24/7.http://www.abatement.com/air-purifier/learning-center-advanced-air-purification-technology.htm


http://www.abatement.com/pdf/cap600-1200-brochure-1109.pdf


I plan on building a shower and changing room, when you enter any plant room, first you shower, then change into freshly washed growroom dedicated clothing/shoes, anyone handling clones wears gloves and uses quat-am religiously, anyone entering flower chambers wears lintfree jumpers with hood, and beardnet if necessary.

Moses and architect are right on the money!! Please read!

 

[shredGnar]

how easy is it to run a sealed room with Gavitas?

Just as easy I would suppose.. I run large adjust a wings which also cannot be aircooled..

You just need the proper cooling and dehumidifiers

 

[Mikell]