ventilation queries

[maryjanebagerly]

hey guys, im working on installing some sort of venting for my cabinet. i have been researching and was wondering if anyone had any suggestions.

my grow space is about 58" tall 21" wide and 28" deep.
ive got a 400 w lamp thats going to be suspended from the top of the cabinet to hang above the plants (duh) but i dont know what kind of fan to install...
im thinking of some kind of kitchen vent hood or bathroom vent fan... the electrical part of this operation is not my strong point so any suggestions,advice, or product opinions would be appreciated!

 

[NamelessCitizen]

Stanley Blower

This is one option that is reasonably priced and can be modified to ventilate your space.

Peace, love and nugs...
Nameless

 

[Guest]

Does your 400W lamp have a hood that you could pull air through? Might we get a few more specifics about your setup, sir?

Les

 

[maryjanebagerly]

well the lamp has little vents , but no way to attach a fan without drilling holes into it/ no attachment for a hood. my cabinet basically looks like a refrigerator, and the light is a rectangular beast that will hang from the top inside of the cabinet... the light has a glass panel in the front for some heat diversion. the little vent slits are located on the side of the light though so i was thinking of just cutting a hole in the side of the cabinet and attaching a fan to suck air out from the side of the lamp to help lower the temp (also i am probably going to take the ballast out of the lamp to help the temp inside the cabinet) . my grow area does not permit much as far as exhaust goes so all i really hope to accomplish is venting (the cabinet is in a room that is not connected by air vents to the rest of the house and instead has its own portable ac unit) for the heat from the light. i have been shopping around for fan attachement unit stuffs but i am shooting in the dark... and as far as the stanley blower goes... i may do that for intake air but idk about the venting just to get the some heat off the light. i may just be insane or paranoid, but i am trying to get my ideas in order just in case of it getting too hot when my plants take this cabinets virginity ^_^

 

[budvapor]

my space is a little smaller than yours, and i use the following:
- stanley blower to extract the air. it works really well.
- tiny fan, like $6 at wallmart, blowing directly on the 400W bulb.
- batwing reflector, no glass etc. blowing directly on the bulb is enough.
- remote ballast--this one's a must.

there's a lot of ways to go. look in the design/equipment forums for other ideas.

 

[budvapor]

HTH believe me, i was surprised too! i went from a 150 security light to this 400w from htgsupply (real good deal too!) and my temps are better now. ambient is 70-80; inside is 2-4 degrees more.

now i made other changes at the same time. i added a stanley blower to the flowering room. before i just had one in the veg room, which is connected to the flowering room with a 8" duct. i reckon that's a bit restricting; the stanley blower doesn't seem to pull very hard. now that i have two, both on the same speed, it moves the air really well.

also, before i had a big ass custom hood for the 150 that didn't vent well. now the batwing is nice, small, aluminum, and i have a little fan blowing right on it and the bulb, and then in the path of the air is the stanley blower's intake. so i think it almost acts like an air-cooled setup...

my plants have already responded in a matter of days by fattening up and packing on more trichs! woohoo!

 

[Guest]

You do not need a Stanley blower for your cabinet. The Stanley blower is VAST overkill for a cabinet that size.

I would recommend a Dayton 265($89.95). It's all the blower you need, even if you use a carbon scrubber. Keep in mind you have a very small volume to ventilate. This is a squirrel cage blower and is made to work against a resistance e.g. carbon scrubber. The Daytons are FAR less noisy than either the Stanley or Vortex blowers ( I have a Dayton 465, the next bigger one and it is very quiet IMO). I'd go with the Dayton 265 if I were you. You'll be fine.

Make sure you get the input adapter flange($9.95) so you can easily hook up your 4" dryer vent tubing to it. And depending on your specific setup, you may want the output adapter flange($11.95) too. These flanges are easy to put on and make hooking up dryer tubing a snap.

As said, make sure you vent from the top of the cabinet. No need to punch holes in your lights hood, although you can if you want. The volume of air exchange using the Dayton 265 will not allow any appreciable heat to build up. Your cabinet is 58x21x28=34104 cubic inches, or 19.7 cubic feet. Without a scrubber, the 265 will move over 250 cubic feet of air per minute. At that rate the TOTAL volume of air in your cabinet would be changed over 12 times a minute!!!!! or once every 5 seconds!! Your cab will NOT get hot. Even if you add a scrubber and cut the blower volume to 1/3 of it's rated capcity, you will still be changing the air 4 times a minute, or every 15 seconds....still plenty enough air exchange to keep that cab cool.

I know math is tedious, but the above is why you don't need that horse of a Stanley blower.

Those prices can be beat. I bought my Dayton 465 $20.00 cheaper at Graingers than the grow supply place. The adapter flanges I bought at the prices I mentioned from the grow place (Discount-Hydro.com) So shop around.

GL

MT

EDIT add:

I vent my grow(430 Watt lamp) into the bedroom it is in, a small 9x10 bedroom with NO ventilation. The window is shut for security reasons. This summer, I just had a cheap 20" common box fan blowing in fresh air through the doorway. The grow never went much over mid 80's.

You should put your passive intake holes at the bottom of the cabinet. Air at floor level is the coolest air in the room, often 5 degrees cooler than eye level air. I know because I measure it all the time. Get a RadioShack "wireless" indoor/outdoor thermometer and RH meter($39.95). Very slick device. It will measure temperature and humidity inside and outside your cabinet. No holes, no wires. Works like a champ. You'll be able to monitor the the two most important parameters of your grow under normal conditions. I set my main unit by my input air supply blower(you shouldn't need one). That way I know temp of air going in and the temp of the grow. It's very handy and you need to know these temps IMO.

If you have A/C in there you DO NOT have temperature worries. Just vent that cab as described above. you'll be fine IMO.