New 2x4x6 grow cabinet (2) 240W7-band HTG LED - Ventilation Guidance Requested

First, thanks for taking a look and double thanks if you can give me some direction. I plan to use this box to grow 3 plants. This will be my first grow, unless you count the bag seed male that I grew under a Kmart grow bulb in a closet a looong time ago.


Primary question: Is there any reason that I cannot place my (in order of flow) C filter, fan, duct muffler( haven't bought the muffler yet, imagine the green ruler is the muffler), flex hose to outlet port, all inside the insulated grow box that I'm building? My only fear would be condensation in the fan's electrical enclosure. Should I be concerned about this? System specs as follows, also cut sheet on the fan.


Secondary question: Are (2) 3" inlets enough intake for the 4" fan running @ low speeds?


System:
2'x4'x6'h custom insulated cabinet
(2) 240W 7-band HTG LEDs (haven't bought 2nd light yet as I want to see how plants will veg under just one)
(1) 4" HTG Grow Bright 170cfm fan
(1) Variable speed controller (yet to purchase)
(1) 4" HTG duct muffler
(1) CAN 9000 C filter


I know the fan will be loud and am looking to see how quiet I can get it. I've done a fair amount of research. The best I can tell, I should be aiming to Change the full volume of air in the box once or twice every five minutes. If this is correct, and if I assume that the filter will bring the fan efficiency down by 50% (shouldn't be that bad by research but haven't seen curves for this specific combo), then at wide open the fan should be moving 85 cfm. As my box is 48 cuft, then I should theoretically be able to turn the fan down to 35% or so and still maintain a negative pressure (the box is well sealed except for (2) 3" PVC light trap intakes). This coupled with the whole contraption being located in the box should give the stealth I'm looking for...... Please disabuse me of this notion if my noob calcs are off base.


Thanks for any advice. Pics follow.

Bubba

The board in the pic will actually be the roof of the cabinet, so you can get some scale. Also gives idea of general light placement, everything should clear ok... I think.



Fan spec sheet



General shot of interior size and shows light trap intakes



The box (still needs stain and diamond foil - sorry about the pic rotation - gave up trying to fix it). I built this in modular panels so I can get it down in the basement.

Bump... Just once, if no reply I won't bug you guys further.

all i can tell u is run ur set up. u should see a 10degree temp difference between ambient and cab temp. i wouldnt dim down the fan because anything lower then the 85cfm is going to make temps more then 10 degree temp difference.

Thanks much for the info. I was under the impression that the LED lights were pretty efficient with heat, like you said I'll run it and watch temps and adjust fan as far down as possible and still maintain a vacuum. Also, box will be in basement - never gets over 68F down there.

yea ur in good shape, do it up it should be on point used an equation to get the rating u should use. just make sure to have double the size of ur exhaust fan with passive intake holes (no exhaust fan)

Ok, thanks. I was planning to use (2) 3" intakes, but this won't give the the 2X factor you suggest, I'll return the 3" stuff and go with (2) 4" passive intakes. Much appreciated. If I knew how to give you a rep, I would lol. The FAQ says there should be a button... not sure if I have posted enough to have that privilege.

lol yea dont worry about the plus rep..its the star near journal this post...u dont need or want intake fans unless ur growing in a very big room. also passive intakes prevent odor leaks since all air is sucked into ur cab instead of being pushed in. this gives u negative pressure in ur cab which is what you want.. is odor an issue? i can send u some links of grows like urs if u want to see what u could be looking at..

Thanks again. Yes, odor control is top priority. With children, just get a lot of traffic through the house and don't want it to smell like a skunk. Any links would be appreciated. This forum is tremendous, but there is almost too much info to sort through.

i hear that!
vent info https://www.icmag.com/ic/showthread.php?t=112862
grow faq http://www.drugs-forum.com/growfaq/GrowFAQ%20Basic%20Topics.htm
lots of useful links https://www.icmag.com/ic/showthread.php?t=97792

Thanks. I actually had the first link, which is excellent, but the other 2 links have massive info well organized. I've booked marked them and will pass them to another noob someday

no problem. yea do that make them read!