Bigger Fan.. Less Heat???

[bigbudmike]

So im building a stealth grow cab. out of a bunch of DIY stuff from my first couple of grows but im running into some heat issues. The fans im using are a couple of POS DIY (small fan stuffed in a bucket). My question is.. if I spend the money and buy a 170cfm centrifugal fan from the hydro store will it help my heat prob? My cabinet is about 2'd x 3'w x 4't and it gets up to around 87 degrees. hear are a few pics of what I got going. You will see that there are two 150w HPS in a home made cool tube. I have one POS fan for Intake and one for exhaust that draws through the cool tube. I was thinking if I put a real exhaust fan pulling through the cool tube then that would eliminate my problem. Any suggestions would be appreciated.

 

[TruenoAE86coupe]

Yes it would help greatly, but make sure you buy an "inline" fan not a "duct booster" fan. The duct boosters don't have any pressure, so your carbon filter would cut the air flow enough that it wouldn't help at all.

 

[bigbudmike]

Found a kit at the local store for a fan and filter goin for $250. A little high for me but if thats what it takes then its worth it.

 

[jondamon]

Something else to consider about your design

Every 90degree angle in ducting reduces your fans efficiency by around 20-30%.

I would personally try and get all ducting as straight as possible between fans and lights and exhausts etc.


J

 

[bigbudmike]

This makes sense, I have two 90's on the exhaust side and only one on the intake side. Not sure i can do much better than that. Did a full day test to day while at work and the temps actually reached 94. this is very disappointing because I was trying to make this cabinet look as inconspicuous as possible. Wouldnt look really good with an AC unit hanging out the side of it. Any other ideas on how to get the heat out? I was thinking it might make a difference to get a real light designed for this sort of thing. not sure if it would make that big of a difference or not. If I were to buy a light / Fan / filter combo would it do alot better than all my homemade crap? Is it really worth the $450 that the guy at the store wanted for the 400w light, fan, and filter?

 

[bigbudmike]

Ok I broke down and bought the expensive fan and im watching the Temps slowly rise up. Just passed 82 and I hope thats it. I could deal with 82 but the old 94 was just ridiculous. Is 82 gonna be to high? It seems a little high to me but I think it will work out. Still got some tweaking to do. I also got the Carbon filter

 

[bongmarley2009]

82 is alright, but if I was you I would try to lower the temperatures to 78ish.

$450 for what type of reflector, ballast, bulb?

You should be able to cool that cabinet and lights with a 4" inline fan. If it's too noisy or too much, add a fan speed controller. Just make sure you have fans blowing the heat from the light up towards the exhaust and your heat situation should be taken care of.

And I don't know where you live, but you may want to check out plantlightinghydroponics.com because it's cheaper for me to order the majority of my equipment from them as opposed to buying from the local hydro store.

Edit: I have grown in a 2'x2'x4' and a 3'x3'x6' tent so I know how important heat exhaust is.

 

[bigbudmike]

It was a sunsystem air cooled 400w HPS with a 170cfm Eco plus 4" fan and a small Phresh brand carbon filer. I got the Fan and filter for $240 and he wanted $200 for the light. I am still disappointed about the price but it is working good. I have dropped the temps by 12 degrees

 

[bigbudmike]

Ok so here are a few pics of what I have accomplished. With out the Filter it was keeping the cab at about 81 to 83. I just got done putting the filter on and am waiting for it to heat up in there. I dont think its gonna make a big difference (hope not at least). I also aimed the Exhaust up and am drawing my intake from under the cab. If you guys have any other ideas on how I can cool down the cab let me know please. I cant go with any off the wall ideas though because I want this thing to look totally inconspicuous. Im gonna run the light cycle at night so that if my land lord wanted to stop by in the day it would all be shut down and he couldnt tell anything was up.

 

[bigbudmike]

I think I finally figured it out! I put each 150w light on its own timer and set them to run for an hour and 45min then turn off for 15min. I alternated the timers so that when the left bulb comes back on the right bulb will run for 45min then turn off for 15min and vise versa. Once I figured it out it seemed like a pretty easy solution. I end up with 9 hrs of 300w and 3 hrs of 150w during flowering and the temps range between 80 and 83.

 

[FootClan]

I think I finally figured it out! I put each 150w light on its own timer and set them to run for an hour and 45min then turn off for 15min. I alternated the timers so that when the left bulb comes back on the right bulb will run for 45min then turn off for 15min and vise versa. Once I figured it out it seemed like a pretty easy solution. I end up with 9 hrs of 300w and 3 hrs of 150w during flowering and the temps range between 80 and 83.

Ok dude whats your ambient temp in the room your box is in?? Thats what really matters.......Your cab is always going to be hotter then your ambient temps so if your room is 75 degrees then your box will NEVER be 75 degress unless you have a AC so just food for thought.. also i wanted to make sure that your exhaust the air outside......are you?? IF not then your just pissing in the wind really.....

 

[Stonetech]

Hey BBB are you still using the crappy fan for intake? You should probably ditch that thing and just make a larger passive intake, it would really improve airflow.

 

[bigbudmike]

Ok dude whats your ambient temp in the room your box is in?? Thats what really matters.......Your cab is always going to be hotter then your ambient temps so if your room is 75 degrees then your box will NEVER be 75 degress unless you have a AC so just food for thought.. also i wanted to make sure that your exhaust the air outside......are you?? IF not then your just pissing in the wind really.....

I been keeping the AC at 72 and the room is around 75. I wish I could set up a system for the exhaust to vent outside but I live in an apartment and its difficult to provide unnoticed outside access.

 

[bigbudmike]

Hey BBB are you still using the crappy fan for intake? You should probably ditch that thing and just make a larger passive intake, it would really improve airflow.

no I switched to a 170cfm centrifugal fan. I now have the fan pulling the air out of the cab through the carbon filter and across the bulbs.
I have a 4 inch passive intake tube sucking air from under the cab.

 

[FootClan]

I been keeping the AC at 72 and the room is around 75. I wish I could set up a system for the exhaust to vent outside but I live in an apartment and its difficult to provide unnoticed outside access.

No doubt its difficult but i live in an apartment to and i have figured out a way to exhaust out side with out anyone noticing.....If your ever interested in how i did it id be happy to share with ya....

 

[bigbudmike]

No doubt its difficult but i live in an apartment to and i have figured out a way to exhaust out side with out anyone noticing.....If your ever interested in how i did it id be happy to share with ya....

I did a little research and think I have a general idea on how I want to accomplish it. If you wanted to post a pic of the way you set yours up I wouldnt be upset The main problem I have is that at any given time I have to go out of town from a few days to a week (a friend will watch over things while im gone) for work and sometimes my landlord will give me very little notice about inspections to be done. I want the whole system to be set up so that if he stops by he wouldnt be able to tell anything was going on. Was planning on running my lights at night and during the day all will be quite and unobvious. Right now I have accomplished this, When you walk up to the cab during the day you cant tell anything is up. I would really like to keep it this way.

 

[FootClan]

I did a little research and think I have a general idea on how I want to accomplish it. If you wanted to post a pic of the way you set yours up I wouldnt be upset The main problem I have is that at any given time I have to go out of town from a few days to a week (a friend will watch over things while im gone) for work and sometimes my landlord will give me very little notice about inspections to be done. I want the whole system to be set up so that if he stops by he wouldnt be able to tell anything was going on. Was planning on running my lights at night and during the day all will be quite and unobvious. Right now I have accomplished this, When you walk up to the cab during the day you cant tell anything is up. I would really like to keep it this way.

Well my setup is totaly contained to the sparebedroom of my two bedroom appartment......My roof leaks alot and they have sent roofers and maintance poeple over on several occasions... I also made sure that the attic access to my attic was not in the room i would be growing in because i know that if they ever need to get in there it would cause an issue....

Everytime they come over i just turn my fan off and close the door to the room and they just come in to into my master go into the attic through the closet and then they go...I have had them come to fix the toliet and the disposal........Ive had comcast here many times...No ones ever even asked whats in the spare bedroom... So for me its worked out pretty perfect.....

Also i put the entire grow togeather in a way that could be taken down and boxed up in less then 8 hours...... So it can be done pretty easy if you just plan ahead before you start buying and building.. i started my plan before i even picked which aprtment id live at..I picked my apartment based on how i wanted my grow to be......That made the most difference in how it all turned out.....

 

[LordHelmet]

not sure if this helps but i use alot of 24 vdc coxial fans.. like the ones in desktops and such. they move air around and i can force alot of heat up and towards my exaust so the grow space never really fills with excess heat from bulbs. these fans are great to use to blow air over a ballast and keep everything cool.
just an option cause noise is an issue for me with the bigger fans

 

[FootClan]

not sure if this helps but i use alot of 24 vdc coxial fans.. like the ones in desktops and such. they move air around and i can force alot of heat up and towards my exaust so the grow space never really fills with excess heat from bulbs. these fans are great to use to blow air over a ballast and keep everything cool.
just an option cause noise is an issue for me with the bigger fans

I curb the noise with my 4ft silencer that makes the most difference

 

[Stonetech]

I been keeping the AC at 72 and the room is around 75. I wish I could set up a system for the exhaust to vent outside but I live in an apartment and its difficult to provide unnoticed outside access.

I grew in an apartment once too, my biggest worry was the sound. Where i live its against the 'tenancy act' to enter a renter's apartment without 24hrs notice, though i do realize that not all landlords follow the rules.

I ran an AC in my room as well with my apartment at ground level (which really sketched me out). Be sure to take a good sniff around the AC exhaust when yer in flower, if there's odor escaping through it you could be the last to know.