4000 watt room setup. Ventilation help

[simpleword]

Hey there, I'm new to IC but was a long time member of OG. Me and four others are planning a new grow in an empty room in my house. We all have our recommendations and can have up to six mature plants each. I have attached a basic diagram of the room below (click the thumbnail for a bigger image). Now, we are thinking of running 4 1000watt HPS lights, maybe even 5 so that we could have at least 50 watts/square ft.

My main problem is ventilation. There is a nice sized closet inside the room which has the house's water heater inside it. The water heater closet (within the other closet) is drywall with no paint or stucco, so it would be rather easy to drill holes and run vent tubes out of it into the "attic" and outside. We could also probably run ventilation through the vents in the room, and lead them outside as well.

Could some of you experienced growers maybe take a look at the room diagram and make suggestions for ventilation options? Perhaps what types of fans (and what cfm) and where. We can't use the window at all, so that's not an option. Any help is much appreciated.

Thanks!

 

[simpleword]

bump.

 

[Guest]

My advice is that five people knowing about a grow is four too many.

 

[Buzzsmirk!]

take this diagram your questions and most inportantly your MONEY to a local/nearby hydroponics shop and have them hook u up with the "KNOW"

BUZZ!

 

[Guest]

One of the most intelligent "first posts" I've ever seen on here or OG,I can see you have a good grasp on that aspect of growing.Its definately not a team sport O god I wish I could convey to you how much its not a team sport!!I just hope when you learn firsthand there are no negative consequences involved.

 

[simpleword]

One of the most intelligent "first posts" I've ever seen on here or OG,I can see you have a good grasp on that aspect of growing.Its definately not a team sport O god I wish I could convey to you how much its not a team sport!!I just hope when you learn firsthand there are no negative consequences involved.

Thank you very much for your response. I know what you're saying, however, these are my three best friends that I've lived with for a long time. I have never had any problem with them whatsoever. We all have our medical marijuana recommendations and live in a county that follows the state (california) laws very well. So this will be completely legitimate.

Thanks again.

take this diagram your questions and most inportantly your MONEY to a local/nearby hydroponics shop and have them hook u up with the "KNOW"

BUZZ!

Thank you as well. I may just end up doing that, however, living in rural area means that I have to drive over an hour to the closest hyrdo shop and more like three hours to a decent one. I was just hoping to get some input before I have the chance to get to a hydro shop.

 

[Feek]

Build a large A/C into the wall in the closet, vent to wherever and seal the room. I don't know the size of that bigger closet, but if you want to make it into a mother/veg room, build the A/C into the water heater closet, and put an intake and outtake going to the flower room on a thermostat. Then, you're sharing the A/C usage between both rooms.

 

[iamtallpine]

4000 watts

4000 watts

I run 4000 and I use 2000hps and 2000mh. Not sure but I think this prevents them from growing though the ceiling.

 

[simpleword]

Build a large A/C into the wall in the closet, vent to wherever and seal the room. I don't know the size of that bigger closet, but if you want to make it into a mother/veg room, build the A/C into the water heater closet, and put an intake and outtake going to the flower room on a thermostat. Then, you're sharing the A/C usage between both rooms.

Thanks, I really like that idea. I already have a window AC, so that could work well. I just bought 4 air tube reflectors for the lights, and I plan on ducting them through the closet as well. So I would have the ac cooling the room and the inline fans pulling the heat out of the tubes. Would the AC be sufficient for fresh air or should we also have another vent pushing fresh air into the room?

 

[SmokeyPufmaster]

The Ac should do it, just don't skimp on the size of the unit. It takes a lot of btu's to overcome 4k.

 

[simpleword]

Cool, thanks. It's winter here and outside temps are in the 20's and 30's. I should have no problem getting extra cold air if needed. Thanks again.

 

[Feek]

Thanks, I really like that idea. I already have a window AC, so that could work well. I just bought 4 air tube reflectors for the lights, and I plan on ducting them through the closet as well. So I would have the ac cooling the room and the inline fans pulling the heat out of the tubes. Would the AC be sufficient for fresh air or should we also have another vent pushing fresh air into the room?

If you wanted to cool tube the lights, then the A/C you'd need would be relatively small (5K max), since at that point, it'd just be a climate control for the ambient room temp. With that setup, make sure your intake and output for the cool tube ducting are both outside the room.

Personally, I think that's just a pain in the ass dealing with all that ducting. My opinion is that you get a strong A/C (12K) and seal the room. Think of it this way - the cold (front) side of the A/C should be in a completely closed off environment, where the hot (back) side of the A/C can be vented however you want. This controls smell and environment in one shot. You can even put a bucket of water off to the side in the room where the A/C is to keep the RH up. Try a few grows in the room before you decide you want CO2.

True, you won't be able to get the plants as close to the lights, but with 1000 watters, you don't want them too close anyway. Besides, if you tilt the cool tube you have slightly, you'll create a chimney effect where the hot air will rise out the top and make the lights a slightly cooler.

 

[Joe A. Grower]

Thanks, I really like that idea. I already have a window AC, so that could work well. I just bought 4 air tube reflectors for the lights, and I plan on ducting them through the closet as well. So I would have the ac cooling the room and the inline fans pulling the heat out of the tubes. Would the AC be sufficient for fresh air or should we also have another vent pushing fresh air into the room?

Basically I see two possibilities here. First, a completely sealed room with AC, CO2, and possibly aircooled lights. Second, a vented room with aircooled lights only during the summer.

If you go for a sealed room, then I would remove the closet door and build a false wall in its place with an opening for an AC unit. Also make an opening to run the output from your air-cooled lights (if you use them). The closet then becomes your "hot area." You'll need to bring in cool air from the outside into the closet, and then vent the hot air back outside (or you could just vent directly into the attic). You'll also need to bring in cool air from the outside for your aircooled lights. If you just suck the air from the growroom out through the cooltubes, you're taking your CO2 and stink with it.

If you don't air cool the lights, you'll need at least a 15,000 BTU AC to cool four lights. With aircooled lights, you can get away with less, but I would still shoot for 10k to 12k BTU in order to deal with summer temperatures. Believe me, you don't want to have an under-cooled growroom in summer. If you room is over 95F for very much of the time, you'll have a truly shitty harvest. I've seen it happen, and its not pretty.

If you don't want to do CO2, then don't bother with the AC. You're going to have to vent anyway to keep fresh air in the growroom, so you might as well do your temp control with venting as well. If winter temps are in the 20's and 30's where you are, don't bother with the cool tubes until summer. You're going to need that heat if you are bringing in air that cold. In fact, you'll probably need a heater.

If you control temperature with venting, you're going to need to deal with odor control. That means a big carbon filter and a fan big enough to push the air you need through it. Figure the volume of your room (length times width times height) and divide it by three. That's the fan rating you need to replace all the air in the growroom every three minutes. Then you double that to account for the backpressure of the carbon can filter. By my calculation, you need ((7.5 * 9 * 10)/3 ) * 2 = 450 cfm. A Vortec 6" model would work just fine. Don't get some cheap shit, or you'll regret it.

 

[Joe A. Grower]

Thank you very much for your response. I know what you're saying, however, these are my three best friends that I've lived with for a long time. I have never had any problem with them whatsoever. We all have our medical marijuana recommendations and live in a county that follows the state (california) laws very well. So this will be completely legitimate.

Cali, huh? Okay, here's some things you might not have thought about. The statewide limit is "6 mature, OR 12 immature plants." That means you can't have 6 plants vegging while 6 plants flower for a single patient. It is either 6 OR 12. Not a combo.

Now you're trying to put 1000W of light on 6 flowering plants, so you're talking about some pretty good sized plants. A 1000W light works well when covering about 20 sq. ft. That's 3.3 sq. ft per plant, so you're looking at some veg time. Figure two weeks from clone or seed to get them established, and at least four weeks of veg after that. Could be more like six weeks. It'll be faster in hydro, and slower in soil.

I see three ways of doing this and staying in compliance with SB420.

First way is the one room strategy. In this mode, you run the whole room as one. Make or buy between 24 and 48 established plants. That is, you want fewer that 12 immature plants per patient. Start vegging them under one of your lights until they get too big for one light, then go to two lights, then three, then four. Once they get big enough to where they will cover at least 50% - 70% of your tables, cull them down to the best 24 female plants (6 mature plants per patient) and flip your lights to 12/12. The stretch will take care of filling in the rest of the table area. Harvest once ready, and repeat.

This is by far the easiest way to run it, but dead last in terms of efficiency. You're going to be spending a lot of time with one to three of your lights off while they veg up.

The second way is to run a veg/flower setup. One patient worth of plants will be vegging while the other three are flowering. On one table you have 12 immature plants (one patient times 12 immature plants), and on the other three you have 18 flowering plants (3 patients time 6 plants). When you harvest one table, transfer the best 6 plants from the vegging table, and start flowering them. Then plant another 6 clones or seeds in your vegging area.

This is going to be a lot more efficient because you have more of your lights on at any given time. The downside is that you are going to need to divide the room into vegging and flowering areas. This complicates ventilation and CO2 distribution, and if you don't do it right you'll get light leaks and wind up with a whole bunch of problems in your flowering area. You are also going to have to stagger the timing on your other three tables, and truth is, you probalby will have tables sitting empty in the flower area waiting for plants in the veg area to get big enough. Timing is going to be a bitch.

The third option is to run independent tables. In this scenario, you would veg 12 plants on a table, cull down to 6 plants, and then flower on the same table you vegged on. This makes timing a whole lot simpler, because you can give each table as much veg time as it needs without interrupting the cycle on other tables. Since you'll almost always have plants on other tables either in veg or early flower, you can cut clones from actual production plants when you need them instead of keeping moms.

The down side is you now need to divide the room into FOUR lightproof areas, with all the associated complications of ventilation. You are also wasting a lot of light during early veg while the plants are small. A 1000W light is a whole lot of firepower for 12 little plants. This strategy would have better efficiency that the "one room" strategy, but not as good as a "veg/flower" strategy. The timing would be easier, though, which may be necessary if you want to run multiple strains with widely differing flowering times.

Anyway, I thought I'd stick that out there. Truth is, you probably have too much light for just four patients.

 

[Guest]

this is probably something you thought of already, but you mentioned your water heater is located in a closet in the room you want to grow in. If you need to do any repairs on that for any reason, you will have to do them yourselves unless you want some random plumber tramping through your growroom and compromising security. You seem like you have a pretty good plan so far though and i look forward to seeing how this comes together.

 

[simpleword]

Wow, there's alot of great replies in here. It really gives me alot to think about. I'm probably going to go with the sealed room option using the cool tubes and A/C, and I'll probably go with the one room strategy for at least the first grow as we only have around 3000 bucks to invest in the first grow (already have some supplies). My only problem right now is where I'll get the intake air for the cool tubes. One option I was thinking of is the heater vents. We won't be using the central heat in the house as we have a monitor and we are probably going to be using the 60amp line from the heater in the grow room. Everything else will work fine it seems. I really appreciate everyone's advice, it's really helping out. I have a couple 1000 watt grows under my belt, but nothing like this so it's kind of daunting. I'm sure I'll have more questions, and I'll also be keeping a growroom diary to keep you guys updated.

Oh and irishSoCo, that is definately a problem, and we have thought of it. However, I am friends with a marijuana friendly plumber, so it wouldn't be a huge problem. But still, the less people that know, the better.

Thanks again guys.

 

[Joe A. Grower]

So you've got a 60A line? I assume that's at 220/240V (never heard of a 120V circuit that big). That's more than enough power to run four lights and AC. Figure you need about 5A (at 240V) for each of those lights, and between 6A and 8A (@ 240V) for an AC big enough to cool the whole deal even without cooltubes. (around 15k - 16k BTU's). Shop around and you can get that much AC for $400-$500. You might think about returning the cooltubes and sinking that money into AC. It's not the most energy efficient way to do the job, but its probably the easiest.

Just remember, sealed room = CO2 enrichment. If you aren't bringing in fresh air, you MUST replace the CO2 being consumed by the plants or growth will slow to a crawl. Make sure to budget for (at the very least) a simple regulator/timer setup on a cylinder. A LP gas generator with an actual CO2 sensor/controller would be ideal, but that route is $$$$.$$ (and you'll need a bit more AC to deal with the heat from the generator).

 

[simpleword]

I may do that, thanks. Do you think this would be better than the cooltubes and an 8,000btu AC that I already have? I guess that would mean that the only fans we'd have to have in the growroom would be oscillating fans? I would just have to have a duct fan or two in the closet?

Also I'm not sure if the line is 240volts, I'm assuming it is though. It says 120/240 VAC, but then again, so do all the breakers. I have an electrician friend who's coming up from Sacramento to visit, and we're going to have him take a look and offer advice.

 

[Joe A. Grower]

I may do that, thanks. Do you think this would be better than the cooltubes and an 8,000btu AC that I already have?

Well, "better" is kind of relative term. Cooltubes are a very energy efficient way of removing heat. Using the cooltubes will let you use less electricity. (Not an astounding amount, however. Your lights will still dominate the energy usage.) The downside is obviously dealing with the ducting for the tubes. All that ducting can also become a pain in the ass when you are trying to move lights around.

Another thing to consider is that cooltubes aren't the greatest at throwing a nice, even, efficient light pattern. Generally, standard hood fixtures do a better job. They restrict airflow more, though, and need a bigger fan to get the same cooling as a cooltube.

If you don't give a crap about a few extra bucks a month worth of electricity, then screw the cooltubes and just buy more AC and use standard, non-cooled light fixtures. It will make your life easier.

I guess that would mean that the only fans we'd have to have in the growroom would be oscillating fans? I would just have to have a duct fan or two in the closet?

Yup and yup. You probably want two in the closet -- one for your intake and one for your output. Its better to direct the flow where you want it to go rather than letting the pressure from one fan push or pull the air wherever it wants to. (like through the unpatched hole that you left in the false wall to your growroom)

Also I'm not sure if the line is 240volts, I'm assuming it is though. It says 120/240 VAC, but then again, so do all the breakers. I have an electrician friend who's coming up from Sacramento to visit, and we're going to have him take a look and offer advice.

If it was for a heater, it is almost certainly a 240V circuit. If you look at the breaker in the box, if it is a "double pole" breaker (like two single breakers connected together), then it is a 240V circuit. I would recommend having your electrician friend run that line to a subpanel in your growroom. (this is a little "breaker box" like your big box). Have him wire up four 15A, 120V circuits for your lights (I assume your lights use 120V -- most do), and a single 15A, 240V circuit for your AC. Most AC units in the 15K BTU range or larger use 240V. If he's really nice, he'll wire up the plugs for you too.

The whole job wouldn't take me more than hour or two, and I suck as an electrician. If your buddy is a pro, he'll probably spend more time at Home Depot picking up the parts than he will wiring the thing.

 

[Merman]

I don't want to hijack the thread but:

"Cali, huh? Okay, here's some things you might not have thought about. The statewide limit is "6 mature, OR 12 immature plants." That means you can't have 6 plants vegging while 6 plants flower for a single patient. It is either 6 OR 12. Not a combo."

Joe: Do you know what the definitions for 'mature' and 'immature' are (Cali)? I didn't know about this part. I usually keep three or four Mothers for variety. Are they considered part of the 6 mature? Would I be out of compliance with 3 Mothers with 6 flowering? Sounds like that's the case....Damn! And then there's the clones! Now I'm really screwed up!

Simple: I think Joe got some good advice for ya'. With my recommendation, I'm using a 400W and my yields are perfect for my use. Any more and I'd be way out of compliance.


Six site SCROG under 400W. 2'x3'x42".



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