Loud Noise Issue - Intake Duct Problem - Looking for Advice&Help!

Fred Flintstoner

Fred Flintstoner

Active Member
Hey All, if there is one thing I have found from being a member here its how much good advice people have for so many different issues.

I believe my grow room is pretty much dialed in, I am just having a slight noise issue.

Quick breakdown:

Grow room is in a closet about 10 ft wide and at each end on the inside of the closet I have a 4" Can Fan Mounted low to the wall. These two fans each take their air from ports that I have created by drilling a 4" diameter hole through the side ends of the closet. Here are pictures to hopefully make this more clear:

Outside Shot of Right Side of Closet
White Round Port is where air is taken in:




Inside Shot of Right Side of Closet
(ducting runs from wall port over through fan to grow room off view)



(ignore black hole..that is getting patched..old stuff)

PROBLEM:

The noise from the air being sucked through the 4" port creates a loud wooshing noise from both vents. If it werent for this sound, there would be zero noise and light coming from my grow closet. It is considered my final milestone as far as keeping this as stealth as possible. :blsmoke:

As you can see their is a diffuser within the center of the port hole. This helps reduce the noise but it just not nearly enough.

I CANT setup fan speed controllers and turn the intake fans down because the air flow intake needs to be optimal in order to keep the temp down in my hot climate and keep up with the more powerful exhaust fans within each room in the closet.

I CANT take air from the crawl space because it is far too hot in there 6 months out of the year, and the only room adjacent is a bathroom so no dice there either.

Thats where I am at.

Any and all help, suggestions, comments, questions, more than welcomed.

Thanks much :bigjoint:
-Freddie

 

Attachments

captiankush

captiankush

Well-Known Member
A couple ideas...

Insulated ducting may help, not sure if the sound is from the air rushing through the ducting or not. I cant think of a way to actually slow the intake velocity...maybe a 90 degree bend from the wall to the ducting?

Will think some more on this one.

CK
 
Mr.GreenJeans

Mr.GreenJeans

Well-Known Member
Fred Flintstoner said:
"I CANT setup fan speed controllers and turn the intake fans down because the air flow intake needs to be optimal in order to keep the temp down in my hot climate and keep up with the more powerful exhaust fans within each room in the closet.

I CANT take air from the crawl space because it is far too hot in there 6 months out of the year, and the only room adjacent is a bathroom so no dice there either. "

Without getting too specific, where do you live??? I live in an area where we regularly get into upper 90's to triple digits in late July and August. Even when it is that hot the air under my house is in the low-to-mid 80's at the absolute hottest.

Is there a way you can tap into A/C ducting??

Click to expand...
 
D

Defcon9

Well-Known Member
Can you build anything around the intake? What I would try (this worked for my buddies 8" fan) is to take some ideas from car audio. Dynamat is a good sound insulator and if you really want to go crazy you can get the dynamat extreme. I built a box around his fan and lined it with dynamat exteme and the sound difference was amazing. The extreme is also heat reflecting. Sound is basically vibration, so if you can eliminate that you eliminate the noise. I would start with the insulated ducting that is a great start. If you can get behind your vent (inside the wall type of thing) and actually put dynamat inside the wall before you mount andthing that might help, or build a faux wall that is really sound proofed in front of your duct. Check out dynamats web site and see if you can use any of that stuff. It might help if you can figure out how to fit it into what you are doing.

Slightly different senerio, but my house is almost 50 years old, so it's not anywhere near new. The duct work through the house would bang and clunk with the heating and cooling. I got a bunch of dynamat and slapped it over the worst spots in the ducting that were banging and one spot on the floor everytime you walked would bang. Once I covered the really bad areas I randomly started to just slap it on all spaced out over the ducts. My house is now silent, completly night and day difference. All they do is sound insulation for home and car. Amazing product, just watch your wallet, it can get expensive. I think I put about $400 worth on my ducts and that really wasn't that much.

Good luck, hope this helped.
 
S

spandy

Well-Known Member
4'' ducting is hard to keep quite. What I did was stuck a 6'' to 4'' reducer on the intake side of my fan, which allowed me to use 6'' ducting for my intake. Built a box around my fan as well but my main problem was just the noice create from alot of air trying to rush down a 4'' hole.
 
LuckyLou

LuckyLou

Active Member
Same problems here. I "masked" the sound by moving an aquarium next to the duct. Between the fish tank filters and the air pump nobody can discern the sounds coming from my special room.
 
Fred Flintstoner

Fred Flintstoner

Active Member
spandy said:
What I did was stuck a 6'' to 4'' reducer on the intake side of my fan, which allowed me to use 6'' ducting for my intake. Built a box around my fan as well but my main problem was just the noice create from alot of air trying to rush down a 4'' hole.
Click to expand...
THANK YOU for everyone's contributions so far. Right now I am letting ideas hang out there in case a few more come in before going solid with anything.

The above quote by spandy is EXACTLY the issue i face 100%. Perhaps larger ducting is the only way if I can not mask the noise effectively?
 
You must log in or register to reply here.
Top