fan/filter and hps cooling advice

Hi all,
I'm in the planning stages of gutting a cabinet, its about 3' wide, maybe 2' deep, and maybe 7-8' tall (cabinet goes from floor to flush with ceiling). I was looking at a quantum 400w dimmable digital ballast (has 75% option or 100% option, figured I could start at 75% and check temps) with a Digilux 400w HPS bulb and super sun2 reflector/hood.
With my 600w phantom and Diglux bulb I'm cooling with a 6" cooltube and a 6" 335cfm cap valueline fan with a can fan (unsure of size/model but its a really heavy short/stout one). Would this fan be overkill? Also, what carbon filter should I pair up with this? I saw smaller can filters like the Can 1500 and the Can 9000 which looked attractive due to their small size, however, I just read online the max cfm's for those is like 40-50 cfm I would run the ducting off the fan to the roof/attic vent and just let it blow straight into the outside air.

Can I get your guys advice on what fan/filter I should pair up with this 400w HPS? Thanks!

400w hps in that space you'll want to get a good 6" fan that pushes at least 300CFM with a carbon filter that's capable of at least 330CFM. The slightly oversized filter helps to eliminate 99.9% of the odour.




J

Ok, so I will need a large filter because I need higher cfm to cool the light..

Yes but not only that.

If you have 300CFM of fan power then the filter must meet or exceed the CFM of the fan otherwise air will be drawn too quickly through the filter and it won't clean the air sufficiently. That's the reason filters have CFM ratings too.



J

I see, thanks for the info! I hope my existing filter has enough cfm for its set up, I have to keep the light about 4-6" from the top of the canopy. For this cabinet I was just looking to do maybe 2-4 in dirt staggered a month from the other garden.

Will a Can 33 filter be adequate for the 335 CFM 6" valueline fan? I'm having a hard time making sense of the numbers listed on their website:
Max Recirculating (Scrubbing) CFM: 400 cfm / 700 m³h
Max Exhaust CFM: 200 cfm / 350 m³h

Does that mean if you are pulling in air through the filter you cannot exceed 400 cfm and if you are pushing air into the filter to not exceed 200 cfm? I believe this is the same filter I use with my current setup by pulling air into the filter and I haven't had any odor problems that I have noticed.

It says maximum exhaust CFM 200. This means only suitable for fans rated up to 200CFM.

SO no it will not work.


J

What is the 400 cfm for then? pushing air into it? I find it hard to believe I have to buy the monster Can 50 which says 420 cfm for exhaust and increases the price by 130$. Is there anything around 300 cfm for around 100$? Local shop had the can 33 for 67$ (197$ for Can 50).

The terms of the CFM in your pasted section mean

It can be used with a 400cfm fan in a recirculating room system. This is where you do not exhaust out of the room and you supplement Co2 and use AC to control temps. The carbon filter and fan run in the room stand alone without exhausting. This filters the air within the room. When you use Co2 you seal your grow room. In this situation you can use a 400cfm fan.

The other option is having it as part of your grow room exhaust.

Carbon filter --- FAN --- out of the grow area using ducting.

In this situation its only good enough for a 200cfm fan.



J

I have a CAN-LITE 6" good for around 350CFM or 600m3h.

It cost me around £70.



J

Looks like these range about 140$-170$ on USA sites. I guess another other option is to purchase a fan speed controller for about 25$ and then just slow the fan down. I'm guessing if 335 cfm is adequate for 600 hps then it's going to be more than adequate for 400w HPS (I was also possibly planning to run it dimmed to 75% so 300w) so if I slow the fan down to 70% that would put me just over 200 cfm and keep the budget for my filter below 100$..

I guess so yeah. But there isn't any way of really knowing what CFM your fan is pushing when dialed down.

Also what if your temps get too high while its dialed down, you crank it up and smell the house out.


J

jondamon said:

I guess so yeah. But there isn't any way of really knowing what CFM your fan is pushing when dialed down.

Also what if your temps get too high while its dialed down, you crank it up and smell the house out.


J

Click to expand...

That's true, I wouldn't know the actual cfm but I run my ducting all the way up through the attic to the attic roof vent so it just blows outside, so the worst case is that the air outside gets a little stinky. I haven't been able to smell what I have right now in week 7/8 with my Can 33 attached and my 6" fan running at full speed 335 cfm. I never use my filter until week 8 anyway so I suppose I could get started with everything and see how low I can run the fan while monitoring the heat in there.
Thanks for all your help, wish I could give you more +rep.

Picked up the fan, realized it was 435 cfm, going to have to really slow this guy down... Although my existing one is running at full speed pulling from a can 33..

Heres what i squeezed into a 3 foot wide cabinet.

The Filter is a ORGANIC AIR Charcoal fiber filter 6"
Max flow is 942 cfm its attached staight to a 6" vanted air hood.
10 inches long... 130.00

The hood is a DAYSTAR by hydrofarm W/hinged glass door. Nice feature easy removal for cleaning. 22.5 inches long...

I purchased a Lumatek LK 400 watt hps electronic digital dimmable ballast.

Hortilux enhanced spectrim 430 watt buld.

With a Gro 1 inline duck fan. 435 cfms kinda loud but a 25.00 fan speed controller fixed that. I built a 1/2 mdf box and mounted the fan inside then with a box (25 feet) insulated 6 inch ducting. That quited right down.

These 4 items were 386.00 with free shipping from hydro galaxy best prices i could find and had free shipping not sure if thats still going on or not. Took them for ever claims fan was on back order but got here none the less.

The filter i bought from the local shop and was the shortest filter i could find. 10 inches critical.

Filter 130.00
Fan, bulb, hood, and ballast 385.00
Fan controller 25.00
wood for box and screws 25.00
6" insulated duct 25.00
power strip 30.00
dual outlet timmer 20.00
Another 5.00 bucks for duct clamps and rip ties.

So I got around 640.00 bucks invested and it works great.

My cabinet is 36 wide 18 deep and 6 foot tall. its only been up and running for 3 days now and it keeps temps between 3 - 6 degrees above room temp.

It barely fits in the cabinet the filter is to close to the end of the cabinet so it cant draw from the tip of the cone filter but it fits and the 6 inch vent line runs up through the top of the cabinet. The fan is in a box above the cabinet on the shelf and is vented to the attic.

I have not grown anything in it so not sure how good the filter works. I've had no odor to filter yet. Waiting on seeds.

A 4" filter and fan combo, can or active air,etc, will work fine for a 400.