Cooling 4kw of HID

[t33to]

Hello All,

I will be cooling 4 x 1000w hps sometime in the near future. The room is around 12 x 12 with 8 foot ceiling. I guess my question is how much cfm do I want on my dump fan? Is it important to vent all of the air in the room "every" minute? Or is it ok if it takes 3-5 minutes?

 

[mtn121]

20,000 btu AC. No matter what you do in the summer it won't work with out AC. Tape your hoods no air leaks, use insulated ducting. Air leaks cause heat. Pull air from out side the room and exhaust it out side the room. Needs to be stand alone never entering room doesn't need to be filtered. Just push air through the lights not pull. I go with a 10 inch fan be safe and get the 12 inch on a controller will be quieter.

 

[PuReKnOwLeDgE]

20,000 btu AC. No matter what you do in the summer it won't work with out AC. Tape your hoods no air leaks, use insulated ducting. Air leaks cause heat. Pull air from out side the room and exhaust it out side the room. Needs to be stand alone never entering room doesn't need to be filtered. Just push air through the lights not pull. I go with a 10 inch fan be safe and get the 12 inch on a controller will be quieter.

I disagree...

It is very possible without an AC, and 20K on 4k aircooled is overkill.....

However you do make an excellent point about pushing air directly over your bulbs with no contact with growroom air. This will help keep your cfm's at a max since there is no filter attached.

I have grown for the past three summers indoors with no AC and multiple 1K lights.

I run 4K HPS in a 16L x 11 W x 7H. For hoods I use 6" cooltubes, they have a 8" 750+cfm inline in the front pulling off a carbon filter, a 6" inline booster fan in the middle, and a 6" inline fan 440cfm on the rear dumping it out the window.

It is manageable where I live, high temps in my grow during the summer are around 79-82F. Run your lights at night when it is cooler to help. Also I have increased my active intake since last summer and I am hoping to keep it down a little lower this year.

Your fans will need to be on 24 hours a day, if heat is that big of an issue, go sealed, get an ac, and get co2 $$$

 

[t33to]

I disagree...

It is very possible without an AC, and 20K on 4k aircooled is overkill.....

However you do make an excellent point about pushing air directly over your bulbs with no contact with growroom air. This will help keep your cfm's at a max since there is no filter attached.

I have grown for the past three summers indoors with no AC and multiple 1K lights.

I run 4K HPS in a 16L x 11 W x 7H. For hoods I use 6" cooltubes, they have a 8" 750+cfm inline in the front pulling off a carbon filter, a 6" inline booster fan in the middle, and a 6" inline fan 440cfm on the rear dumping it out the window.

It is manageable where I live, high temps in my grow during the summer are around 79-82F. Run your lights at night when it is cooler to help. Also I have increased my active intake since last summer and I am hoping to keep it down a little lower this year.

Your fans will need to be on 24 hours a day, if heat is that big of an issue, go sealed, get an ac, and get co2 $$$

Umm, I just want to use a non sealed room. Use a canfan or something to dump the air outside and bring in cool air from the outside. I don't plan to use air cooled hoods either. I'd like to use the parabolic shades. I was just curious how quickly do I need to be able to completely change the air in the room... every 1 minute? every 5 minutes?

I appreciate the replies still.

 

[Orygun]

I don't think thats very doable without air cooled hoods or ac unless it stays very cool in the summer where you are.

 

[Bud Bug]

Not gonna work with open shades. You can still get some of the heat out if you hook up duct to the top of the shade and suck the air thats collected underneath the bulb but thats very limited.

Normally in a sealed room with burning Co2 you need about 12K BTU for every three bulbs.

Also running co2 allows you to run higher heat in the room but you'd need to use a bottle as burning gets more heat and humidity which = even more heat.

 

[dtfsux]

The OP doesnt want to run a sealed room, thus no AC or CO2.

He wants to know how often to exchange the room.

I think CanFan says every 2-3 minutes for heat exchange. Personally I would try for every minute, get alot of fans in there to move air around, and off those hoods. Obviously make sure you have a filter on the exhaust air.

 

[whodair]

get rid of the hoods if you wanna lower temps a bit. you may have to experiment with your environment and may not get it dialed on your 1st run. are you using a filter or blowing smelly air out of the room??

 

[t33to]

get rid of the hoods if you wanna lower temps a bit. you may have to experiment with your environment and may not get it dialed on your 1st run. are you using a filter or blowing smelly air out of the room??

Yes I will definitely be using a filter on the extraction fan. I will also run an additional smaller scrubber in the room. I will try and get a fan that changes the air every 2-3 minutes. I think in the summer I may switch over to the air cooled hoods just for the summer. What kind of square foot light spread can I expect to get from those air cooled hoods?

I would like to grow bigger plants and less numbers... I thought parabolics were better for that, but please correct me if I'm wrong. The reason I don't like the air cooled shades is all of the duct work and the lack of flexibility in your mounting options.

 

[mtn121]

Pureknowledge- 5k byu per 1000watts air cooled is standard if you want full temp control. I can drop my temps to the low 60's with light on easy. I don't have a high temp because it stays were I want it to at 75. Sure you can run less but its not as efficient and the AC runs all the time.


T33-As far as your situation. I think air cooled is a must with out AC. Just remember high temps will cause airy flowers and lower yield. If you can pull cool air in for now you will make it just make sure you put filters on all of your intakes to block mold and insects. You can use a house filter and rig it around the hose if needed it works. If you wanna pull cold air your exhaust will have to be away from your intake wherever you are getting air from outside at.

 

[t33to]

Pureknowledge- 5k byu per 1000watts air cooled is standard if you want full temp control. I can drop my temps to the low 60's with light on easy. I don't have a high temp because it stays were I want it to at 75. Sure you can run less but its not as efficient and the AC runs all the time.


T33-As far as your situation. I think air cooled is a must with out AC. Just remember high temps will cause airy flowers and lower yield. If you can pull cool air in for now you will make it just make sure you put filters on all of your intakes to block mold and insects. You can use a house filter and rig it around the hose if needed it works. If you wanna pull cold air your exhaust will have to be away from your intake wherever you are getting air from outside at.

Ok, maybe you guys have sold me on the air cooled set up. What kind of hood do you suggest for a 1kw HPS over 4x DWC-r buckets per lamp?

What kind of light spread could I expect from a shade like the first one shown here?
http://www.bustan.ca/product_detail.asp?menuID=4&SID=28&PID=264

 

[dtfsux]

Theres a big thread that Pico did testing hoods. He liked the SS2 but did not test the Radiant 6. I tested the Radiant 6 and SS2 and the Radiant 6 was better than the SS2.

On average, 600's are good for 3x3, and 1000's are good for 4x4

 

[Phillthy]

i cool 4k with no air cooled hoods and do it with a 12.5k btu mini-split. 18k btu would be ideal, 24k overkill.