Correct placement of a filter?

[keith1975]

I am starting to think my filter isn't connected correctly. Please see below and let me know which is the right way:

Blue = Filter
Orange = Extracot Fan
Red = Duct

I currently have my setup as A. But I'm thinking B or C might be better.

In A, the filter (blue) is inside the tent, and a duct (red) is attached that goes outside the tent, where the extractor fan (orange) is pulling from. I dont think this is working. My theory is that the "pull" from the fan isn't that strong, because it isnt directly attached to the filter. It has to work through the whole pipe and still suck air through the holes etc. I.e. I believe there is resistance.

Option B is similar to C. In B, the air is push out through the duct. And in C, it's pulled out and blown through the filter. Because there is so much air coming out the other side of the filter, I'm thinking that blowing that through the filter might work better. I.e. C.

Which is the best and why? Does it even matter?

 

[TurboBucket]

They are all perfectly acceptable.
Your current method is the most recommended as all the air leaving the tent goes through the filter first. The duct is held in a negative pressure so no smelly leaks and the small amount of heat from the fan motor is outside the grow space.

Duct work provides negligible pressure drop compared to a filter.

 

[Greenlizard]

I personally run as per figure (B) but figure (A) looks just as efficient...
Are you experiencing odor or just second guessing a new install?

 

[Gadfly]

I’ll add to the confusion by choosing C. I like to pull my air out from the top where heat builds up. If I’m a cool space I suspect that wouldn’t be an issue though.

It doesn’t really matter as long as you can create the negative pressure in your tent. Each of those can do that

 

[nivek]

agree on pulling the air from the top,, heat is what one is trying to remove,, mostly,, i know odour as well,, but heat,, hot air rises, so, just seems logical

 

[TurboBucket]

hot air rises, so, just seems logical

Hot air only rises when allowed to stratify. Other than that it will move to the area of lowest pressure

 

[nivek]

@TurboBucket

technically,, perhaps,, and thank you for making me research that,,

however,, the top of the grow room is where the lights are,, usually a few more electrical components as well,, and the warmth,, if not the warm air,, accumulates there, over time,, the surfaces get warmer, and stay warmer.

i will bet my next ounce of best bud on that

cheers friend,, good conversation,, indeed

 

[Greenlizard]

I too prefer to suck air from the top of my tent but I still fall under example (B).
This photo was taken prior to having the duct attached.

 

[Dwight Monk]

According to the guys at the Hydro shop when I bought mine, the filters are designed for you to pull air thru them instead of pushing the air thru them like in figure C, kind of like your car/furnace air filter does.

 

[nivek]

According to the guys at the Hydro shop when I bought mine, the filters are designed for you to pull air thru them instead of pushing the air thru them like in figure C, kind of like your car/furnace air filter does.

sheesh,, of course,, absolutely correct,, each way forces the air thru the filter a different way,, one, outside to in, the other , inside to out.

the filter, i would think, is made for one direction specifically, if not one way only.

no wonder you are a monk,,

 

[Dwight Monk]

the filter, i would think, is made for one direction specifically, if not one way only.

no wonder you are a monk,,

Well I decided to ask as I wasn't sure when I bought it, never really looked to see if there is an arrow pointing up out of the filter flange. But yeah they are designed to work one direction and are probably more effective that way, as the outside part probably a "prefilter" and then it goes thru the carbon and then out (so wouldn't makes sense to run thru a filter element after the carbon).

 

[keith1975]

It doesn’t really matter as long as you can create the negative pressure in your tent. Each of those can do that

The negative pressure would cause the tent to “pull in”. Which my tent wasnt doing with the filter. I removed the filter today and a lot of my heat and humidity problems went away. I dont know if my filter is broken, or if im using it wrong, but it causes no air to leave the tent. For now i dont need it, so im just going to trod along....

 

[nivek]

ummm, have to ask,, did you remove the plastic wrapping?

 

[Greenlizard]

Can you upload a photo for us to see your filter and fan?

 

[keith1975]

ummm, have to ask,, did you remove the plastic wrapping?

Yes I did. And also asked the shop I bought it from if I'm doing something wrong. I'll post a photo a little later. (getting a normal light that will allow me to take proper pictures)

 

[SmokeyMcFly]

Most filters are designed to be pulled from so your setup sounds right. What kind of fan do you have there are two types of fans. One type is a cheaper booster inline fan made to keep the air going on long runs and the other kind has the power needed to suck air through something like a carbon scrubber. If the fan made of almost duct metal and was like 40 bucks or less you probably got the wrong kind, a pic will help be sure