Grow Room Feedback Please - Intake and Exhaust Configurations

[Bestbud]

I've had 2 successful grows (one auto and one PP) using the intake and exhaust configuration below but not without the challenges of heat, humidity and odor control. My tent is 3' x 3' x 6' (54 cu. ft.) and it's in an interior closet that is 6' x 10' x 9' (540 cu.ft.) and without direct heating or air conditioning. I believe the problems are:

(a) I'm exhausting the hot humid air from the tent into the closet and even though the intake and exhaust aren't near each other, the exhausted air ultimately becomes the intake air.
(b) even though the exhausted air is carbon filtered, the smell is very noticeable.

I'm trying to avoid the expenses associated with project like adding direct heating, air conditioning and ducting (whether permanent or temporary) and thought that since the exhausted air ultimately becomes the intake air why not vent the exhaust air back into the tent along with fresh air from the closet that's hasn't been compromised with the tent exhaust air.

I know that typically exhausted air isn't used as intake air but in the proposed configuration I'm using it in conjunction with fresh closet air. Any pro's and con's to my abstract thinking?

 

[dickfitzwell]

cuz why even use the filter if you want to do that

 

[Animatey]

There is no point taking the fan exhaust back into the tent with ducting. In the second picture if you remove the peice of duct that leaves the tent, and then re-enters it, you have the same configuration. The fan is moving air within the tent with or without the ducting.

Are your temps too high? Is your humidity too high? I wouldn't try to solve a problem you don't have.

Is the smell the problem?

I have found that most the time when my carbon filter doesn't work it is because the fan pulling air through it is pulling too hard.

I have also found that putting a fan connected to a filter in the grow room outside the tent (in this case in your closet), does a good job of scrubbing small rooms. Setting something like this in your closet next to your tent with a fan speed controller to slow the fan:


https://econosuperstore.com/wp-cont...Virgin-Charcoal-Odor-Filters-351417373456.JPG

If you actually have temperature issues, the best option is probably to vent into the attic.

 

[AutoWonders]

My preference will always be intake (low sock) across from exhaust (high sock). To draw across/through/up plants, then out.

 

[Bestbud]

cuz why even use the filter if you want to do that

Thanks for the read and reply. I agree that the filter would be useless in the proposed configuration.

 

[Bestbud]

There is no point taking the fan exhaust back into the tent with ducting. In the second picture if you remove the peice of duct that leaves the tent, and then re-enters it, you have the same configuration. The fan is moving air within the tent with or without the ducting

Thanks for taking the time to read and reply to my post. I agree with you, no argument. My goal is not go outside the closet (i.e. exhaust ducting) and to solely use the environment in the closet. One question I have is whether or not ducting the exhaust back into the tent preserves the environment in the closet for cleaner intake?

Are your temps too high? Is your humidity too high? I wouldn't try to solve a problem you don't have.

Temps inside the closet and tent are almost identical, average 82F and 60%RH which is too high for the other stuff that I'm storing in the closet.

Is the smell the problem?

Smell isn't a problem for me (too much blow in the 80's and 90's) but for my wife it is. I'm tired of hearing that the "$70 carbon filter isn't working".

I have found that most the time when my carbon filter doesn't work it is because the fan pulling air through it is pulling too hard.

A REALLY GOOD thought - my intake is an AC Infinity S6 with a speed controller (350 CFM) but my exhaust is an Active Air 6 inch In-Line Fan (400 CFM) with no speed controller. I usually have my intake on half-speed which means that I'm pulling new air in at 175 CFM and pushing old air out at 400 CFM - an area that I probably need to rethink.

If you actually have temperature issues, the best option is probably to vent into the attic.

Agreed but one of my goals is not to go outside the closet.

 

[Bestbud]

My preference will always be intake (low sock) across from exhaust (high sock). To draw across/through/up plants, then out.

Thanks for the read and the reply! I like your thinking and I think in my current configuration I accomplish that.....intake on lower sock on left and exhaust starting on the upper right with the carbon filter, then the muffler and then the exhaust fan.....or did I misinterpret your post?

 

[dickfitzwell]

One question I have is whether or not ducting the exhaust back into the tent preserves the environment in the closet for cleaner intake?

you can do that by just letting it blow out the fan in the tent no need to run it out and around then back in. just filter + fan placed into the tent with nothing attached.

 

[Bestbud]

you can do that by just letting it blow out the fan in the tent no need to run it out and around then back in. just filter + fan placed into the tent with nothing attached.

I like the simplicity of your configuration, filter-muffler-fan exhausted into the tent....no need for exhaust ducting. However I think [HASHTAG]#Animatey[/HASHTAG] has identified a flaw in my current configuration:

My intake fan is pulling 175 CFM which is renewing the entire tent of 54 cu. ft. 3.2 times every minute.......meanwhile
My exhaust fan is pushing 400 CFM which is evacuating the entire tent of 54 cu. ft. 7.4 times every minute.......NOT GOOD!......CAN'T BREATHE! - This may also be a contributing factor to the short stature of my plants.

My short term fix is to crank-up the speed controller on my intake fan to it's max of 350 CFM which will almost balance intake and exhaust. Once my current grow is over in 3-4 weeks I'm going to purchase another AC Infinity S6 and then I'll truly be able to allow my carbon filter to work properly by not pulling air through too hard.

 

[BII]

Your goals should be to vent/exhaust heated air and filter it before it gets into your home or outdoors. Seems most everything you want to do involves venting everything right back into the same closet, a closed system, just going to heat-up. And there is no "fresh air from the closet" with everything being vented into it. If it's too hot, you need to get rid of the heated air and replace it with cooler air (one way or another).

Also, I'm pretty sure you want to muffle the noise at the exhaust point. Put the muffler as the very last thing.

Regarding your fans, with that size tent, just using that main exhaust should be more than good enough to move air through rapidly (stale air from the closet).