Fan size for fridge grow?

[old blue]

I'm starting to set up my fridge vegging box, and i was wondering what is the smallest cfm and type of fan i can get away with, for the cheapest price? I'll be having a 2' 2 tube t5 lighting it, so not much heat will be produced. I'm cutting holes in the bottom rear of it to use as passive intakes, and cut holes in the ceiling of the fridge section, up into the freezer section. I'm going to be exhausting via some type of small fan, out of the top rear of the freezer section, (which will also be used as cloning chamber).

I didnt know if a 120mm computer fan wud be sufficient or i also found a 65cfm squirrel fan on ebay pretty cheap? Or can i just go with a 4" duct fan from homedepot? Any help would be appreciated.

 

[curiouscat420]

i JUST had this idea the other day looking at my two old fridges in my garage... excellent... take some pics!!

 

[curiouscat420]

.... on ebay pretty cheap? Or can i just go with a 4" duct fan from homedepot? Any help would be appreciated.

although this situation shouldnt matter, you should watch what you buy off ebay... especially when you get into this sort of equipment...

My idea had was to make the freezer where i put my ballast and my exhaust and everything else pretty much... the fridge would only have the light and the plants. I would use one fridge for Veg/Clones and another for flowering...

great minds think alike!

 

[old blue]

although this situation shouldnt matter, you should watch what you buy off ebay... especially when you get into this sort of equipment...

My idea had was to make the freezer where i put my ballast and my exhaust and everything else pretty much... the fridge would only have the light and the plants. I would use one fridge for Veg/Clones and another for flowering...

great minds think alike!

Oh, i know. I'm very cautious. It's not a hydroponic fan, it's actually to exhaust some type of heater or something. I think i'll go with the homedepot one tho. Wont have to worry bout prying eyes.

And if u look in the "lights" section on here, you'll see my fridge thread that i started. I'll be taking pix as it progresses.

 

[GeezerBudd]

I found a formula at a greenhouse supply site:
Length of area X Width of area X (Height X 1.2)= CFM'S required
These CFM'S can be split between the intake and exhaust.

Does'nt the fridge already have one fan?
I'll be looking for fridge pics.
Got one in my shop too.

Gb

 

[old blue]

I found a formula at a greenhouse supply site:
Length of area X Width of area X (Height X 1.2)= CFM'S required
These CFM'S can be split between the intake and exhaust.

Does'nt the fridge already have one fan?
I'll be looking for fridge pics.
Got one in my shop too.

Gb

I removed the lil fridge fan, cause the bearings were shot. I just found this 120mm computer fan on ebay for cheap, that boasts 130cfm. Tell me if its worth it to buy.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=280305969647

 

[old blue]

Or how bout this 62cfm one with power cord already attached???

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=110340791400

 

[GeezerBudd]

Well okay-my take on Ebay:
Iv'e bought a few things over the years from Ebay-mainly for my sideline business.
Most of the time I was not shorted, but a Couple times I was like for instance, it showed a picture of a complete implement and DID not say incomplete or anthing.When it was delivered, only half was there.
It was a small purchase anyway, so I did'nt go through all rigermorow
of contesting it.

You need to measure the fridge's interior, then use the formula I posted.
It is for greenhouse ventilation.

Ebay-You're on your own, IMO.

Gb

 

[old blue]

Well, i started my fridge buildout today. I scrubbed it down with bleach water really good and let it dry out. I gutted all the inside components and wiring. Then i removed the freezer fan and cut a hole all the way thru the back to mount my computer exhaust fan/scrubber(pic #1). Then cut holes in the bottom of the freezer section for airflow(pic #2). I then cut 2 holes in the bottom of the fridge to use as passive intakes and to route my power cable out(pic #3). Then lowered the shelf brackets as far as they will go, to use the full height of the fridge(pic #4). I then took a 6 socket bathroom light bar and cut it in 2, and mounted at the top of the fridge section(pic #5). I will be alternating the sockets by using a Y on the 1st one, then a single bulb on the 2nd, and then another Y on the 3rd. And on the opposite side, i'm going to go singe, Y, then single. So the end result is all the bulbs will be staggered and pretty much fit into the others free space, to use all the space(pic #6). I'm using 9 26w daylight cfls, instead of the original plan of a t5. I'm gonna have a lil over 11,000 lumens, and just over 2 sq ft.

 

[GeezerBudd]

I would have routed the power cables out of the side closer to the top, and loop them so moisture does'nt run down them, but...Thats me.

Hey, that does look nice and clean-I think the ladies are gonna love it!!!!


Gb

 

[WeedHopper]

I started like that. Let them grow for about 3 weeks in vegg,,untill I built my Closet Growroom. If you look real close ya can see the seedlings.Those are now grown and in Flower.

 

[old blue]

Ok, so i got my fridge grow up and running, with 1 clone in it so far. But there is a slight problem. When i have it shut, the temps by the 9 cfls get up to around 100*! And that's even after having a 8" fan to circulate air AND a 130cfm computer fan exhausting air thru the freezer section. So, temporarily i went down to 5cfls, since i only have 1 clone in it so far, to keep temps bearable. And they're still 90-92 when unit is closed up.

Here's a question for u wiring experts. My fan is a 130cfm, 12v 0.9amp fan. The only power supply cord i could find was a 9v, 1 amp cord. So i wired it up and it seems to be throwing some decent air. But i was wondering if it would make a significant diff to use a 12v cord instead of the 9 i'm using? How many cfm do u estimate i'm pushing using the 9v?

I deff need to find a fix before i can introduce another clone and put all the lights back in. I also thought that maybe it'd be wise to move the 130cfm fan to the top of the fridge section(right behind the lights), instead of the freezer section where it is. Or maybe get ANOTHER 130 cfm fan to install there, and keep the one in the freezer. Also, i only have 2 roughly 1 1/2" dia inlet holes in the bottom, is that sufficient, or shud i make more? Please, any advise would be appreciated.

 

[curiouscat420]

i wouyld go for a 400W HPS and cooltube... it will fit and you can have air blowing right through it... drops your temps in half... those cfl's are probably running more power anyway... and they are hotter without having a cool tube... almost a necessity in a cabinet grow room. imo. :bong:

 

[WeedHopper]

Ok, so i got my fridge grow up and running, with 1 clone in it so far. But there is a slight problem. When i have it shut, the temps by the 9 cfls get up to around 100*! And that's even after having a 8" fan to circulate air AND a 130cfm computer fan exhausting air thru the freezer section. So, temporarily i went down to 5cfls, since i only have 1 clone in it so far, to keep temps bearable. And they're still 90-92 when unit is closed up.

Here's a question for u wiring experts. My fan is a 130cfm, 12v 0.9amp fan. The only power supply cord i could find was a 9v, 1 amp cord. So i wired it up and it seems to be throwing some decent air. But i was wondering if it would make a significant diff to use a 12v cord instead of the 9 i'm using? How many cfm do u estimate i'm pushing using the 9v?

I deff need to find a fix before i can introduce another clone and put all the lights back in. I also thought that maybe it'd be wise to move the 130cfm fan to the top of the fridge section(right behind the lights), instead of the freezer section where it is. Or maybe get ANOTHER 130 cfm fan to install there, and keep the one in the freezer. Also, i only have 2 roughly 1 1/2" dia inlet holes in the bottom, is that sufficient, or shud i make more? Please, any advise would be appreciated.

I had to leave the door cracked with a exhuast fan pulling cool air into the fridge and one pulling out hot air,,,but still had heat issues. Ya gotta understand,that fridge is well insulated,,Holds heat in. If its a good freezer,,ya could keep it on and cool I guess. Anyway,,,as I said,,I started like that and it soon became apparent that the fridge is not big enough for a good grow. To small. Anyway good luck Bro. Wish ya the best.

 

[old blue]

I had to leave the door cracked with a exhuast fan pulling cool air into the fridge and one pulling out hot air,,,but still had heat issues. Ya gotta understand,that fridge is well insulated,,Holds heat in. If its a good freezer,,ya could keep it on and cool I guess. Anyway,,,as I said,,I started like that and it soon became apparent that the fridge is not big enough for a good grow. To small. Anyway good luck Bro. Wish ya the best.

I'm not worried bout it being too small. I'm only going to be vegging 2 clones at a time, and have a kind of 3 stage perpetual grow, having 2 plants in veg, 2 just starting out in flower, and 2 more halfway thru in flower. So the size is actually perfect for me. Just got to find a way to keep it a lil cooler. I think maybe i'll get 1 or 2 more computer fans, to have 1 as an intake fan and then have the other as a secondary exhaust. Any thoughts???

 

[GeezerBudd]

Ok, so i got my fridge grow up and running, with 1 clone in it so far. But there is a slight problem. When i have it shut, the temps by the 9 cfls get up to around 100*! And that's even after having a 8" fan to circulate air AND a 130cfm computer fan exhausting air thru the freezer section. So, temporarily i went down to 5cfls, since i only have 1 clone in it so far, to keep temps bearable. And they're still 90-92 when unit is closed up.

Here's a question for u wiring experts. My fan is a 130cfm, 12v 0.9amp fan. The only power supply cord i could find was a 9v, 1 amp cord. So i wired it up and it seems to be throwing some decent air. But i was wondering if it would make a significant diff to use a 12v cord instead of the 9 i'm using? How many cfm do u estimate i'm pushing using the 9v?

I deff need to find a fix before i can introduce another clone and put all the lights back in. I also thought that maybe it'd be wise to move the 130cfm fan to the top of the fridge section(right behind the lights), instead of the freezer section where it is. Or maybe get ANOTHER 130 cfm fan to install there, and keep the one in the freezer. Also, i only have 2 roughly 1 1/2" dia inlet holes in the bottom, is that sufficient, or shud i make more? Please, any advise would be appreciated.

Okay, If I am reading everything correctly here, You are using a passive intake (just holes-no intake fan)

Your passive intake opening should have the same area as the diameter of your exhaust fan.
In other words,for example, if you have an 8" exhaust fan, your passive intake should have an area of 8".
Adding an intake fan might solve the problem with more active air circulation.

 

[CasualGrower]

JMO guys.... A fridge or freezer is WELL insulated..... so heat will be an issue when getting into HID lights.... also you are looking at a Very confined canopy..... Maybe 2' x 18 ". So we are just talking about a few sq/ft.... 3 or 4 lower end (not lowest, I am talking a total of 120-160 watts worth) wattage CFLs would be PLENTY of light for this area for vegging and blooming. those lil bit of lights will generate lil heat, For Ventilation I would figure out the Cubic footage which is gonna be in the 20ish range for most of these appilications and look for a fan that will exchange the air in this small space once every minute...

I would however also look into a thermal switch to turn that fan off and on to help maintain a constant temp in the cabinet... errr fridge.



Did that make sense????? felt like I was rambling....heh

 

[GeezerBudd]

Jeez,
I just took another look at this.
If you have your exhaust fan up in the freezer and the intake holes down in the fridge part, the air is'nt getting into the freezer. you need a hole(s) between the freezer and fridge-I think-If I am lookin at this right.

Gb

 

[CasualGrower]

Yep!

 

[CasualGrower]

Ideally I would use a Fridge/Freezer and a stand up Freezer for a complete grow system of this size....... Use the Fridge/freeze combo for Mother/Veg/cloning and use the Stand up freezer for blooming.