Ventilation. Do I need it and how much i need it?

[Braman]

Hello!
I have read some posts about ventilation and could not find any compromising answer.
I have 1.7x 1.7 x 1.8 meter room.Now it is about +15C in that room, in winter it gets down to about +5 C. To heat up i will be using electric heater. I will be running LEDs( NOOO, dont sugest me to run hps/mh, PLEASE ). The option to get a fresh air for me, is to suck it from outside. Outside in winter periods can get as low as - 20 degrees (ussually 80% of last winters its about -6C to + 3C or maybe less. Somewhere I have read that this sizes room needs 600 m3/ minute ventilation, with this amount my heater will work 100% on and my LED "efficency" will be nowhere.
Could I went such a room with simple bathroom vents 100 - 150m3/minute?
I would like to use extra CO2, I have not searched for automatic CO2 systems. If I won`t find anything where I live, I will just try to produce it with sugar, water and yeast..

 

[coreywebster]

In large grows Ventilation is a must, or at least replenishing co2 is a must. If keeping heat in is an issue then a sealed room is the way forward.
Air exchange is usually minimum of the whole room once every 3 minutes. But if you seal your room, use co2 and use an internal scrubber to clean the smell then your all good. Your grow area is reasonably small and you will probably find you need less air exchange than the old rule of thumb. But as I say with cold temps sealed would be best.

BTW you can and should run LED room a few degrees higher than HPS set ups, due to the lack of IR in LED your leaf temps will be lower, plants can take very high leaf temps compared to air temps, too low of a leaf temp and the plant wont uptake nutrients as well and deficiencies can occur in non mobile nutrients.

I find 80degrees f is a good air temp, if my plants go below 75 in lights on they tend to stall on nutrient uptake and need less watering. Using Quantum boards and citizen 1825 Cobs in a 4x8. Previously used 1800w of HPS for 6-7 years.

I know you said don't suggest HPS, but keep an open mind, for some folks with cold climates its a good way to keep the leaf temp up. No point spending a fortune running heaters if your negating the savings and efficiency of the LEDs. A mix of led and CMH would be a good compromise should you find you need one. Its really about been able to grow the best plants you can all year round.

Oh and when you say fresh air from outside, if you were to vent stale air outside then new air would replace it from the rest of your house. You don't need to bring in outside air unless you are running a hot grow room and you need the coldest air possible. If you go with a ventilated room then if you can find a way to allow the air from your house (presuming you don't keep your house cold) it should be a more reasonable temp and therefore workable.

 

[Braman]

In large grows Ventilation is a must, or at least replenishing co2 is a must. If keeping heat in is an issue then a sealed room is the way forward.
Air exchange is usually minimum of the whole room once every 3 minutes. But if you seal your room, use co2 and use an internal scrubber to clean the smell then your all good. Your grow area is reasonably small and you will probably find you need less air exchange than the old rule of thumb. But as I say with cold temps sealed would be best.

BTW you can and should run LED room a few degrees higher than HPS set ups, due to the lack of IR in LED your leaf temps will be lower, plants can take very high leaf temps compared to air temps, too low of a leaf temp and the plant wont uptake nutrients as well and deficiencies can occur in non mobile nutrients.

I find 80degrees f is a good air temp, if my plants go below 75 in lights on they tend to stall on nutrient uptake and need less watering. Using Quantum boards and citizen 1825 Cobs in a 4x8. Previously used 1800w of HPS for 6-7 years.

I know you said don't suggest HPS, but keep an open mind, for some folks with cold climates its a good way to keep the leaf temp up. No point spending a fortune running heaters if your negating the savings and efficiency of the LEDs. A mix of led and CMH would be a good compromise should you find you need one. Its really about been able to grow the best plants you can all year round.

Oh and when you say fresh air from outside, if you were to vent stale air outside then new air would replace it from the rest of your house. You don't need to bring in outside air unless you are running a hot grow room and you need the coldest air possible. If you go with a ventilated room then if you can find a way to allow the air from your house (presuming you don't keep your house cold) it should be a more reasonable temp and therefore workable.

I would like to use 3/4 of mentioned space with 12 COBs. If I`d run hps, i would need about 3x400w hps or 3x250, thats about 1350w/850w from wall, I cannot make such a high electrical bill. Running 12 COBs I am planing to run on 700ma, thats about 300W from wall.

Now I am confused.. I could make air intake from space where lowest temperature is around 4-5C.
Probably I could just use 100-150m3/min vent as intake and same on output and run them a few minutes every hour, so my temperature is not lowered a lot and heater does not turn on often..

 

[ANC]

Forget about the space for a second, how much do you need to grow how often?
It is easier to work backwards from there.

 

[chemphlegm]

I run a room 12x40 and its sealed up pretty well, not perfect of course.
I have no exhaust and no intake. I did that for a year, nothing but mold, condensation, expensive heat and c02 bills resulted.
When I plugged those holes and sealed it up , opened up my bulbs.....I was amazed at the production results. I needed a larger ac unit is all, more air scrubbers, and now my numbers are spot on year after year, season after season... every plant produces exactly as it should, no molds, no condensations, no issues at all. I'm sure there are some air leaks and I have no positive/negative pressures pushing or pulling. Its an outdoor building with the garden inside one end. The door is open when I work in there, so some fresh air sneaks in surely.

 

[ANC]

As long as I am alone I also prefer just leaving the door open a bit to running that loud arse extractor. I really need to put it on a hygrometer so it just comes on as needed, in the meantime, I am climate control. We have a ceiling fan and an air-con too. I mostly just leave the ceiling fan running. Good for gas exchange and keeping temperatures even throughout the room. It has still been cooler out than in, but spring is here and we are in a drought so it will change, I am sure. If it was up to me I'd run the aircon 24/7, but I'm not paying for the power.

 

[Braman]

Forget about the space for a second, how much do you need to grow how often?
It is easier to work backwards from there.

As much as I can and as often as I can.

I run a room 12x40 and its sealed up pretty well, not perfect of course.
I have no exhaust and no intake. I did that for a year, nothing but mold, condensation, expensive heat and c02 bills resulted.
When I plugged those holes and sealed it up , opened up my bulbs.....I was amazed at the production results. I needed a larger ac unit is all, more air scrubbers, and now my numbers are spot on year after year, season after season... every plant produces exactly as it should, no molds, no condensations, no issues at all. I'm sure there are some air leaks and I have no positive/negative pressures pushing or pulling. Its an outdoor building with the garden inside one end. The door is open when I work in there, so some fresh air sneaks in surely.

YOu did have a sealed room previously and it resulted in molding, condensation?. And how did it raise heat?

 

[chemphlegm]

As much as I can and as often as I can.



YOu did have a sealed room previously and it resulted in molding, condensation?. And how did it raise heat?

no I ventilated the room, air in and air out year round, now I do not use the outside air , in or out.

more heat in a sealed room than in one using the outside air to ventilate right?
The dehuey makes heat, now trapped in room to be conditioned
the c02 gen makes heat , same trap
the lights are now not ventilated to the outside or cooled by the outside air = more heat right?

 

[coreywebster]

I would like to use 3/4 of mentioned space with 12 COBs. If I`d run hps, i would need about 3x400w hps or 3x250, thats about 1350w/850w from wall, I cannot make such a high electrical bill. Running 12 COBs I am planing to run on 700ma, thats about 300W from wall.

.

With 300w of cob you could light up a 3ftx3ft pushing to a 3.5ft x 3.5ft area. You cant light the same space as 1200w of hps with only 300w of cob. They are good, but not magic. You can limit that space to around 1m2 and do very well with it

 

[TheHero]

I do not want to "copy" hps power, I want to cover 3/4 of that area. It is less than 3m2 and on that are, running 12 cobs in my opinion is good way.

 

[chakup]

no I ventilated the room, air in and air out year round, now I do not use the outside air , in or out.

more heat in a sealed room than in one using the outside air to ventilate right?
The dehuey makes heat, now trapped in room to be conditioned
the c02 gen makes heat , same trap
the lights are now not ventilated to the outside or cooled by the outside air = more heat right?

So which is it sealed or ventilated is better cuz you seem to be going back and forth or that bud was amazing and I'm just confused.
Co2 tank doesn't put off heat, that's easy. LED won't have as much heat. If building a 12 cob rig then should have the ability to remote mount the ballasts- heat saved.
Running a split won't add heat to the room, etc. There's options there. I'm going through the same process now and the budget is main thing stopping me. Lol.

 

[chemphlegm]

So which is it sealed or ventilated is better cuz you seem to be going back and forth or that bud was amazing and I'm just confused.
Co2 tank doesn't put off heat, that's easy. LED won't have as much heat. If building a 12 cob rig then should have the ability to remote mount the ballasts- heat saved.
Running a split won't add heat to the room, etc. There's options there. I'm going through the same process now and the budget is main thing stopping me. Lol.

try again...

I used outside air in the past,

and now I do not.

there is no such thing as better, its all about personal choices and limitations.

amazing bud? yes, better controls makes better bud

did bud get better when I sealed it up? yes of course it did because I had better controls.

I dont run a split, and you are correct no heat will be added while using one

notice I said "c02 gen" a c02 generator adds much heat and humidity to the room. I dont use tanks

hope that clarifies for you

 

[TheHero]

try again...

I used outside air in the past,

and now I do not.

there is no such thing as better, its all about personal choices and limitations.

amazing bud? yes, better controls makes better bud

did bud get better when I sealed it up? yes of course it did because I had better controls.

I dont run a split, and you are correct no heat will be added while using one

notice I said "c02 gen" a c02 generator adds much heat and humidity to the room. I dont use tanks

hope that clarifies for you

So, how are you cooling your room?

I guess I will try to make a small ventilation system. For example - 100-150m3/h in and out, through coal filter, that will restrict heat loss when vents are off. And 3-5 minutes per hour of vent work.

 

[chemphlegm]

So, how are you cooling your room?

I guess I will try to make a small ventilation system. For example - 100-150m3/h in and out, through coal filter, that will restrict heat loss when vents are off. And 3-5 minutes per hour of vent work.

with a 12kbtu window shaker mounted in the wall between my grow room and the interior of the barn the room is in . the hot air from the ac unit is ducted to the outside of the building.

 

[justugh]

with a 12kbtu window shaker mounted in the wall between my grow room and the interior of the barn the room is in . the hot air from the ac unit is ducted to the outside of the building.

hey man .,.......thanks this is fun

ok your forgot this
1 what area of the world in what kind of climate (some climates are good for growing with exchange rooms others are not)
u need to get weather info for the last year and look at the avgs.......(like where i live the RH in the air goes up high at night so venting is not a good idea)

2 if your area is one of the good zones stable temps low fluxes in RH .....then exchange room is a option
the math for this is simple the LxWxH of the grow area gives u the cubic feet of the area .......now u want to exchange the air 1 time every 5 mins (this is for heat control) and to build the Co2 up in your area as it is heavy gas

3 now if the area is not good for exchanged room u need to move to a sealed room ......sounds like u are partly there (this is simple u get poly wrap it is 20x100ft if u do it right u can use one sheet and wrap the walls (staple it down then little caulk of the staple) where there are outlets and all u cut the plastic and seal it to wall using duct tape ......the door u get one of the zipper that are designed for poly wrap dust management......the floor is your choice if it concrete tape it down if it is not then lay a sheet down and tape it up ........u have now made a tub (co2 will settle in the room and the oxygen will be pushed out top )

4 sealed rooms are fun and costly ........1 u need a mini split if u have more then one area u can buy a unit that has multi heads but one condenser (i look for units with seer 17 or better with heating and cooling choices for year round ).....2 Co2 Burners (the tanks cost to much invest in a controller and burner u will save money on the propain vs co2 tanks in about 6 to 9 months pays for self........3 Dehumidifier....Co2 burners increase the RH (plus this will help push Co2 gas around the room ) ....4 a Hempa air filter ideally u want to rig a system to clean the air in your area but also spread it around your area completely to help with cooling (plus if u set up on the floor and dump in the air u are spreading Co2 where it is needed most on the bud sights ....allow u to use lower ppm of Co2 but get the results of a higher PPM ...saves u money makes propain tanks last longer)

that should do yah

edit if u can add in a UVC light into the ducting from the hempa filter ....that will take care of any mold spores that get tho the filter but i stull use a lvl 10 filter on the system

 

[chemphlegm]

hey man .,.......thanks this is fun

ok your forgot this
1 what area of the world in what kind of climate (some climates are good for growing with exchange rooms others are not)
u need to get weather info for the last year and look at the avgs.......(like where i live the RH in the air goes up high at night so venting is not a good idea)

2 if your area is one of the good zones stable temps low fluxes in RH .....then exchange room is a option
the math for this is simple the LxWxH of the grow area gives u the cubic feet of the area .......now u want to exchange the air 1 time every 5 mins (this is for heat control) and to build the Co2 up in your area as it is heavy gas

3 now if the area is not good for exchanged room u need to move to a sealed room ......sounds like u are partly there (this is simple u get poly wrap it is 20x100ft if u do it right u can use one sheet and wrap the walls (staple it down then little caulk of the staple) where there are outlets and all u cut the plastic and seal it to wall using duct tape ......the door u get one of the zipper that are designed for poly wrap dust management......the floor is your choice if it concrete tape it down if it is not then lay a sheet down and tape it up ........u have now made a tub (co2 will settle in the room and the oxygen will be pushed out top )

4 sealed rooms are fun and costly ........1 u need a mini split if u have more then one area u can buy a unit that has multi heads but one condenser (i look for units with seer 17 or better with heating and cooling choices for year round ).....2 Co2 Burners (the tanks cost to much invest in a controller and burner u will save money on the propain vs co2 tanks in about 6 to 9 months pays for self........3 Dehumidifier....Co2 burners increase the RH (plus this will help push Co2 gas around the room ) ....4 a Hempa air filter ideally u want to rig a system to clean the air in your area but also spread it around your area completely to help with cooling (plus if u set up on the floor and dump in the air u are spreading Co2 where it is needed most on the bud sights ....allow u to use lower ppm of Co2 but get the results of a higher PPM ...saves u money makes propain tanks last longer)

that should do yah

edit if u can add in a UVC light into the ducting from the hempa filter ....that will take care of any mold spores that get tho the filter but i stull use a lvl 10 filter on the system

what? did you mean to post to the op ?
I'm not seeking a grow room plan, mine has been successful for near a decade with no molds, mildew, mites, rh issues etc. My rh outdoors here fluctuates year round, no matter though because I control it regardless of outdoor conditions. I dont purposefully exchange air ever. I use 1k in scrubbers, c02 gen, dehuey full time, with back ups on standby. I dont worry about spreading cool air, or c02 because I have massive fans circulating the air and my c02 meter stays in my canopy. c02 doesnt move around like a fart, more like water in a bowl.

 

[justugh]

what? did you mean to post to the op ?
I'm not seeking a grow room plan, mine has been successful for near a decade with no molds, mildew, mites, rh issues etc. My rh outdoors here fluctuates year round, no matter though because I control it regardless of outdoor conditions. I dont purposefully exchange air ever. I use 1k in scrubbers, c02 gen, dehuey full time, with back ups on standby. I dont worry about spreading cool air, or c02 because I have massive fans circulating the air and my c02 meter stays in my canopy. c02 doesnt move around like a fart, more like water in a bowl.

opps yah i ment to go to guy posting the string .....my bad

 

[TheHero]

hey man .,.......thanks this is fun

ok your forgot this
1 what area of the world in what kind of climate (some climates are good for growing with exchange rooms others are not)
u need to get weather info for the last year and look at the avgs.......(like where i live the RH in the air goes up high at night so venting is not a good idea)

2 if your area is one of the good zones stable temps low fluxes in RH .....then exchange room is a option
the math for this is simple the LxWxH of the grow area gives u the cubic feet of the area .......now u want to exchange the air 1 time every 5 mins (this is for heat control) and to build the Co2 up in your area as it is heavy gas

3 now if the area is not good for exchanged room u need to move to a sealed room ......sounds like u are partly there (this is simple u get poly wrap it is 20x100ft if u do it right u can use one sheet and wrap the walls (staple it down then little caulk of the staple) where there are outlets and all u cut the plastic and seal it to wall using duct tape ......the door u get one of the zipper that are designed for poly wrap dust management......the floor is your choice if it concrete tape it down if it is not then lay a sheet down and tape it up ........u have now made a tub (co2 will settle in the room and the oxygen will be pushed out top )

4 sealed rooms are fun and costly ........1 u need a mini split if u have more then one area u can buy a unit that has multi heads but one condenser (i look for units with seer 17 or better with heating and cooling choices for year round ).....2 Co2 Burners (the tanks cost to much invest in a controller and burner u will save money on the propain vs co2 tanks in about 6 to 9 months pays for self........3 Dehumidifier....Co2 burners increase the RH (plus this will help push Co2 gas around the room ) ....4 a Hempa air filter ideally u want to rig a system to clean the air in your area but also spread it around your area completely to help with cooling (plus if u set up on the floor and dump in the air u are spreading Co2 where it is needed most on the bud sights ....allow u to use lower ppm of Co2 but get the results of a higher PPM ...saves u money makes propain tanks last longer)

that should do yah

edit if u can add in a UVC light into the ducting from the hempa filter ....that will take care of any mold spores that get tho the filter but i stull use a lvl 10 filter on the system

Thank You for response
My grow room size is about 1.7x1.8x1.8 meters.

I will do sealed room. I will start with yiest/sugar/water mix at start, COBs. So, I guess I won`t need an AC or venting, because COBs wont build such heat. If my skills grow, I will buy Atlas 3 co2 controller and a tank.

 

[TheHero]

Looks like Atlas wont go for me. I have 240V and Atlas 2 - 3 runs on 110V and they do not recomend to use a converter from 240V to 110V.. Any EU systems available?

 

[Jaybodankly]

Vent the hot air into the house. I put in a floor vent, hooked-up some 6" pipe, connected that to my 6" fan/filter combo. Now I have carbon scrubbed warm, moist, filtered, O2 rich air . I plan on setting up a air return from my bedroom and getting all that CO2 while I sleep sent to my flower room which runs at night.