First Cab need advice on ventilation/heat. 150hps

Hello all and this is my very first post and my very first grow
I have already picked up a 150w hps sun system light. I am interested and picking up a metal storage cabinet dimensions 42"H X 36"W X 20"D. I was wondering if i had a 4" 176CFM Typhoon duct fan connected to a carbon filter would it be enough to keep the cab cool and properly ventilated?

Edit: THough i should mention i would be cutting a hole out of the side of the cab and this is where the fan would be attached for exhaust. Any ideas for air intake?

Hey mate, also on my first grow. 150w hps in that dimension shouldnt cause too many problems really, having said that if its a metal storage cabinet heat build up will probably be worse. I suggest picking up a wooden one maybe? upto you...
Well you want more exhaust than intake this way fresh air is constantly being driven into the grow area, so 1 or better still 2 of the 176cfmTyphoon(exhaust) and a simple CPU will probably be adequate for an intake without upping the budget too much Hope i helped and happy growing

I tent is nice to If u can use one

You could always try pc fans wired to a 12volt adapter. Put it high to suck out heat and/or low to draw in colder air. Also, as long as the metal isn't too thick, it shouldn't retain much heat.

Your fine. I have a 150w in a smaller cab. I am going to to 250w in a space slightly larger than yours.

THanks for the replies! I went ahead and picked it up anyways, for forty bucks can't go wrong! Here it is



Its a stealth closest grow so i only have 21.5" of depth and 50" of vertical room before the racks start (plenty of horizontal) so this fits perfectly within my constraints. I Figured I could've built a wood cab, but it would've cost me the same amount of money(if not more) and wouldn't have had a lock on it. Also couldn't find a tent that would fit in besides a 2'x2'x4' which is to big depth wise.

Right now I don't have the cash flow for two of these fans as they are 150 bucks each new at my hydro store. I was told that computer fans although having high CFM and being super cheap, would not push the air far enough away. The closest window is 12' away and would only be able to be open 3-4 months out of the year due to weather. The metal is approximately 2mm thick

V = 3.5' x 3' x (20/12)'= 17.5 ft^3
SA(bottom) = 3' x (20/12)' = 5 ft^2

(17.5 X 60)/176 gives 6 seconds for the fan to clear the whole room of air w/o filter and 12 seconds (assuming CFM is halved) w/ filter

Would i be able to get away w/ just one fan for now and leave room for a second exhaust if needed, then just a have passive air intake w/ a light trap?

EDIT: noneed4me didn't see your post, thanks!

Yeh having just a passive intake should be ok especially for the size just make sure you have a good exhaust creating a negative pressure and all should be good

As obvious as it might be, the point hasn't been made to put the fan as high up closest to the top as possible to draw out the hottest air first. Also, I dont think its very common to run the fans during the whole duration of the photo-period (lights on). also putting two cheep-o intake fans, instead of investing another 150 in another exhaust fan might help cool it down without burning your wallet.

nice catch, with the cabinet. good deal for 40 bills

If its not a stealth cab u can make a DIY fan pretty easy and cheap and depending on the area wher it is u can still hide most of the components

Any updates to this awesome thread? pics would be awesome... I might not be helping.. I did see where you could make the pc fans run off something like a model train power pack.. just in case nobody else knew just curious if anyone thought of adding a piece of duct connected to a flange also. then sitting maybe a small small box fan inside a box.So.. sit a deep box on the floor with a hole cut out, stick a flange through the box, and connect a duct to it. make sense? atleast for fresh air coming in the bottom of your cabinets i think it would work ok... just curious how well this would work with tight quarters in the top. those 150hps can make your 70* degree box upward of 80-90*. so heat is an issue. Although in order to sell the thing, they say it isn't.

Looks just like my veg. Cabinet. Good luck.

I completely forgot to update this after I built the cab. My first run was very successful for a first grow and reached about 80 grams (56 being goal). Currently 20 days from second harvest

Never took any picture of the box specifically but I do have some pics of the first grow that sorta show off the box (pics below)

I was able to control temperature just fine venting and intaking into the same room as long as I left the window open slightly or the bedroom door ajar(both if possible)

Construction Rundown

Ventilation: I drilled 3, 4" holes with a HMS hole saw. One in the far left ceiling which has a 4" inline fan mounted with the brackets provided. Two in the lower right wall which have 4" vent hoods for passive intake that look very similar to this(below). Then bolted the hoods on with some screws/washer/nuts


Lighting: Measured the width of my 150W HPS, then added two metal U-bolts in the ceiling from which to anchor the light. a spring loaded quick fastener attached to chains allowed the lowering/lifting of the light when appropriate.

Cord control: Drilled a hole in the upper centre of the left wall with a 2" HMS hole saw. Fed my inline, light, and fan cords through there and twist tied to keep them neat and bundled.

Reflective Material: Panda film was originally taped with venting tape, but realized after a few days this would not be adequate as it was falling down. This was rectified without starting over with several magnets that I salvaged from a 7.1 speaker speaker set that was blown.

Odour Control: Carbon filter was attached directly to the 4" fan. drilled two holes in the intake fan lip and screwed it it place. Added duct tape and a 4" duct clamp to make it air tight.

Here are the best pics I've got that show off the construction:

Great looking veg room you got there!

What reflective material did you use? It looks like the same they use in a tents. I was looking for something like that but couldn't find the name/shop that carried it hence the panda film.

veg/mother room is next on the list

I have that same light but my grow area is smaller. I can only run it with the door open over night, that is untill I get my A/c ported into the cab. Good looking Grow mad props!