Ventilation Routing Question

So Im curious if this would work. My room is about 60 cubic feet, and I dont really wanna run another fan but I will if I have to.

SO, I have a 170 CFM inline fan(HTG) and I want to pull air through my cool tube and filter with it. Instead of running them in a series, such as:

Filter connects to duct connects to cooltube connects to duct connects to intake of fan

I was wondering why you couldnt do it with a Y-pipe.

1 4" on one side and 2 on the other. If the intake pulled on the side with 1 , wouldnt that create a negative pressure to pull through the light/filter on the other 2 sides?

basically I want to run a seperate intake vent through the light to help keep tems down, and use the same fan for the light/filter. I think the fan will do it, for sure. Im just curious if there are any obvious reasons not too, you know like been there done that kinda stuff.

Seems like a no-brainer to me. For sure it would work. BUT, until it does why not ask the guru's right? The fan sounds like a jet engine, its pretty loud. I setup the speed controller and dialed it down to 2/3 power and my temps are still good but once I setup the filter I think full juice will be needed on the fan. I think my fan can do it though since the current setup is working great.

My temps are low 70's, so even if it got warmer by a few degrees but was able to run everything it would be worth it. I dont really want my filter running through the light in a series because I here that causes needed cleaning in the tube all the time from the carbon.

Any comments on that?

Thanks in advance!

Set up a test and use smoke to detemine if your theory is correct.

greensister said:

Set up a test and use smoke to detemine if your theory is correct.

Click to expand...

The theory was tested last night and is correct, however Im thinking Im going to have to create some resistance on the tube side to keep the pressure on the filter. I think that the resistance from the filter is going to cause most of the air pulled to the fan to come from the cool tube. That side of the setup will make the filter side unable to create pressure, since the air flows freely through the cool tube.

It would be like trying to use a straw with a fat hole in it, it wont work.

SO, i will prolly just have to do it the traditional way like I had it from square one

Filter>Duct>Cooltube>Duct>Intake of fan>Exhaust from room

Unless I can figure out a reasonable way to create resistance on the cooltube that pairs with the filter to even out the airflow.

glyphen said:

The theory was tested last night and is correct, however Im thinking Im going to have to create some resistance on the tube side to keep the pressure on the filter. I think that the resistance from the filter is going to cause most of the air pulled to the fan to come from the cool tube. That side of the setup will make the filter side unable to create pressure, since the air flows freely through the cool tube.

It would be like trying to use a straw with a fat hole in it, it wont work.

SO, i will prolly just have to do it the traditional way like I had it from square one

Filter>Duct>Cooltube>Duct>Intake of fan>Exhaust from room

Unless I can figure out a reasonable way to create resistance on the cooltube that pairs with the filter to even out the airflow.

Click to expand...

Well keep the "Y" set up just use a duct reducer- befor you get to the light, choke it down by half. Just exper. a little(I don't have one of these lights and don't know the heat range on them befor damaging) use some tape to figure out the final size So for instance a duct of 4">2">???

nowAdayz said:

Well keep the "Y" set up just use a duct reducer- befor you get to the light, choke it down by half. Just exper. a little(I don't have one of these lights and don't know the heat range on them befor damaging) use some tape to figure out the final size So for instance a duct of 4">2">???

Click to expand...

Kinda what I was thinking, a 4" to a 2" to a 4" to a 6"(cooltube is 6") and maybe even throwing a furnace filter or something on the passive side of the intake for the light to make even more resistance.

I had everything running last night, and it pull HARD through both sides of the Y. I am just nervous about the smelll 100X more then the heat. My temps are 71-74 throughout the day with the light on, so If it got 5 degrees hotter I would be cool with that. Hell even if it got 7-8 degrees hotter, id still be cool with that instead of fabbing up a second HVAC system.

Ill keep you guys posted, should have the filter on tomorrow with the resistance in place.

Not really sure how to measure it, other then guestimation, but im gonna check it out.

glyphen said:

Kinda what I was thinking, a 4" to a 2" to a 4" to a 6"(cooltube is 6") and maybe even throwing a furnace filter or something on the passive side of the intake for the light to make even more resistance.

Click to expand...

for the smells try some of the active carb. filter wraps(the black stuff) roll it up see what you can fit in to a 6" duct eleminateing the reducer to the lights. You won't have to replace this filter because it's being used to slow down the flow of air and not actually for oder.

Use cig. smoke to see how the pull is one line to the other. seem like you got a handle on it.

Yes, the air will take the path of least resistance. Why not hook them up in one long line? That way all of your exhaust air will have been filtered for sure. Seems like a crap shoot with the "Y" tube.

Little Tommy said:

Yes, the air will take the path of least resistance. Why not hook them up in one long line? That way all of your exhaust air will have been filtered for sure. Seems like a crap shoot with the "Y" tube.

Click to expand...

Well with the Y the one side would have fresh, unstinky air so Im not really worried about that air not getting filtered. I think the negative pressure from the fan will stop any smelly air from creeping back up the other side too.

I cannot seem to get the air resistance even close though. With the filter on the end, reduced to 2" ducting it still is sucking way harder then the filter. If I hook the filter up in a series with the light so there is no Y pipe the filter sucks hard enough I can turn my fan down some. It pulls paper towels off of the ground from 12", not sure how to measure that but its moving some real air through the filter.

Anyways, with the y setup, all the way down to 2" plumbing and a furnace filter its just not making enough suction on the filter to be worth a shit. It wont even hold a paper towel to the filter from the suction with the fan on full blast. The tube sounds like a rocket with all the air cutting through the 2" opening.

Plus Im tired of throwing $10 here $20 there to try and figure this out.

Fuck it, I will run 2 fans.

END OF THREAD

Y pipe wont work.

maybe on a larger scale operation, with baffles, engineering, science and some bowls someone MIGHT be able to figure it out.

But I prefer the cheaper method, Im no longer funding a research project as Im on to the install/finish of my room.
2 fans it is!!!
PEACE!~