How to quite down an inline fan?

I actually have the filter hanging in the tent, and the fan itself is bolted to a stud in my ceiling. Direct connection to a stud made the wall vibrate and resonate into the hum. Letting the bungee cord eat all of the vibration, the sound was gone.

Pictured was before I added the bungee cord, but that's how I have it setup now, it's hanging by a bungee cord.

 

you can buy a muffler for it. That along with a speed controller helps a lot. A muffler and putting the fan in a box full of insulation with a speed controller will get you the most you can do. Obviously, using a slower speed with a controller has to be OK. IOW will you still have enough CFM flow to do the job? Putting a fan in a box is safe. They cool by the air that passes through them.

 

You can buy insulated ductwork. I used to just order ductwork online but I got some at my local grow store last time and had a nice surprise when I opened it. The grow room specific ductwork is black on the inside so it doesn't reflect the light down it like a fiber optic cable.

Insulated ductwork can quiet it down significantly.

Storz reminded me of old school pirate growers I knew back in the 90's. They would make like a speaker box out of particle board and hang the fan from bungies from the lid of the box. You can mount duct attachments to the box and hook the fan up inside. It quiets them way down.

Using oversized ductwork really helps. Part of my jack of all trades name is I used to do HVAC work. I remember a ductwork guy coming in the forums once and crapping his pants that we can run 440cfm through a 6" duct. You would never do that in a house because that volume of airflow in that small of a pipe is way too noisy and it creates a lot of pressure.

If you went to an 8" duct it would also limit your amount of noise. 8" fans flow more air per revolution of the motor and so can pump the same amount of air at a lower RPM and lower air pressure.

 

I have a max fan pro 6 inch 293cfm on low and it is still too loud. The fan itself is quality low noise, but that much air is noisey. I tried a muffler, not much improvement. I run it now with the old filter with prefilter removed on top, about the same as a muffler but a cheaper better option if airflow is not a goal. Controllers hum, variac will work but max fan said if running below low setting of 293fcm fan blade may rattle. Solution? Get a smaller 4 inch fan. You can always use 2, one for grow one for drying. Turn fan off when too loud, turn on when stinky. I just bought one this morning from hydrobuilder for $50 Blauberg Inline Mixed Flow Fan
It's not the fans that make the noise if you have a quality fan that does not rattle and max fan pro is high quality, it's the rushing air. Most of the grow, odor control is not critical for stealth, only certain times.

 

You can buy a silencer for it and insulated venting. The venting really does help like. Ive got a 720cmh fan and while its loudish in the attic i cant hear a thing from under the hatch.
Not tried the silencers but my mate uses em and says theyre pretty good

Sent from my SM-J330FN using Grasscity Forum mobile app

 

The carbon fan adds ventilation, but if you rely on it for that purpose you almost need to leave it on all the time. If it is only used for odor control then it is not really needed in veg and can be turned on when you fear odor is noticable to others. I do not vent my carbon fan. New filter on bottom, fan on top of it, old filter on top of fan, over and over again. Blowing fresh air in actively is twice as good as passive intake IMHO. No, carbon is not neccessary for plants, only for bothersome people.

 

If you are in a legal state and not concerned with smell then as talkative said, it's not a necessity. It is a necessity to have an exhaust fan at least to pull out hot air and help prevent mold.

 

With that being said also, a lot of people only put the filter on during late veg as they switch into flower, as odor becomes an issue, just like talkative said.

 

So the filter is to prevent the aroma of the ladies outside of the tent, it sucks the smell into the filter, and pumps out fresh air and removing heat from the tent as well

 

Well, yes. The main purpose is to remove heat/stinky air, but at the same time if you have the proper amount of area opened up for fresh air to come in, yes. That's exactly what it does.

 

oh yeah baby, got it now. That 4 inch fan with a 6 inch muffler. I bought the 6 inch muffler for my 6 inch max pro and it fit exact;y flush to the fan making it a pain to connect, especially if doing any moving around. But the 6 inch muffler now fits over the 4 inch fan for a secure connection. Quiet in there now. I had a hard time finding a quality 4 inch fan but this $50 from hydrobuilder Blauberg is very quiet and seems to be well built. I always over do everything, but over doing my cfm was driving me nuts.

 

I smoke a lot of dope, it helps hide the smell.

 

You win.

 

Hi,
Look it may sound stupid but5it worked for me. Put it in a vertical way5so it draws from above and push donward in hour filter. Made the hum stoped for me