How do I sound proof furnace intake vent?

[Dunderbeck]

Building similar device

Hi,
Sorry I haven't been on in a few days, I didn't have time to get on.

Are you sure that a cardboard box is enough to build a similar rerouting mecanism as the table with carpet. If it's cardbord instead of wood, or metal, would that make it less soundproof? Also, could I use foam soundproofing, real or homemade, instead of carpet?

I'm very unsure of what to use to make this. I'm not much for woodwork, and don't have a place to build something out of wood anyway. A cardboard box would be easy, but If I did the same thing, cut a hole on one side of the box, filled the inside walls with soundproofing, and attached the flap opening over the vent (using either a pedistal of some kind or a attaching it to the wall) would that be good enough, or should I get something more solid like a table or a vent portion?

If I use something other than a cardboard box, I'm not certain what to use, or how to elevate it to the vent's height. Maybe I'll do the box now, and then look for something more permanent at thrift stores and garage sales. It may take a while; I'm still in the process of setting up the surround system. If anyone's got any suggestions for material I'm all ears. When it's done I'll post some photos, maybe some photos of the building once I start, but I have to figure out how to download the photos from my phone and post them here.

 

[Dunderbeck]

Air Conditioner

I don't care about it as much, but I was wondering if there was a way to dampen the sound of my window air conditioner in summer. I'm assuming there's nothing I can do about that, but if there is a way to lessen the sound I could do it while I work on the furnace.

I've found some soundproofing on line, but I'm still unsure about what to do about the housing. I'll probably do cardboard if that's equally effective as a wood or metal housing.

 

[pureiso]

Instead of carpet, may I recommend either OC 703 or Roxul board. These either 2" or 4" deep will definitely absorb most of the sound extremely well. Roxul board is really cheap to if you can find a local vender. You may just be able to build an acoustic panel to stand in front of the vent about 1' out...

And while you are at it, buy a few more and cover them with fabric. Now you can absorb the first reflections from your speakers to make it sound even better. Ha

 

[Dunderbeck]

Please elaborate

Instead of carpet, may I recommend either OC 703 or Roxul board. These either 2" or 4" deep will definitely absorb most of the sound extremely well. Roxul board is really cheap to if you can find a local vender. You may just be able to build an acoustic panel to stand in front of the vent about 1' out...

And while you are at it, buy a few more and cover them with fabric. Now you can absorb the first reflections from your speakers to make it sound even better. Ha

The OC703 and Roxul board, is this something I'll find at a hardware store? What type of place will have it, and what's it used for?

Please elaborate as to what I should do with fabric and the Roxul to the speakers. I don't fully understand what you mean? Do you mean build a housing for the speakers?

 

[pureiso]

The OC703 and Roxul board, is this something I'll find at a hardware store? What type of place will have it, and what's it used for?

Please elaborate as to what I should do with fabric and the Roxul to the speakers. I don't fully understand what you mean? Do you mean build a housing for the speakers?

It is essentially higher density insulation that is pressed into a rigid board. As far as the comment about the speakers look up acoustic treatments to understand what I mean by first reflections.

This kind of material will absorb more sound, basically reducing the noise further coming from the vent.

As for who stocks it, some HVAC companies will stock it and it is pretty cheap. Also insulation companies may have some as well.

 

[jaymz]

I guess before I did anything, I'd check out the fan components. First, I'd replace the drive belt. A cheap first-step. A belt can look fine, but still be bad. Then check the fan/motor pulleys. If this is an old installation, they could be worn (thus damaging the belt) or the belt could be riding in the wrong place in the pulleys. The fan bearings would be next, especially if they're a squirrel-cage setup. Mostly, these furnace installations use cheap brass sleeve bearings, covered in rubber. After a time, the bearing sleeves wear thru, eventually damaging the fan shaft, or the rubber covering gets eaten away. Another issue is that the fan blade itself could be out of balance.

I would be wary of placing anything in front of the intake grille because it would impact the efficiency of the furnace and perhaps affect combustion gasses.

Jim

 

[Dunderbeck]

Never sure what to say in this feild

I think I'm gonna have the repair guy who recently put up my TV build something like Alex's table contraption. If the vent was near the ground I'd do the same thing with a table, but it's 3 or so feet off the ground (from the bottom not the top), so I'm not sure what pieces of thrift store furniture I could use, unless I put a small table on top of a cart or something, and it would have to fit the dimensions pretty well. I don't have space or tools for woodwork

He said he could do it for $75 which seems pretty good for hand work. Should I have him use Roxul board or another soundproofing, and is it more or less expensive than the alternatives? I could make it out of a cardboard box, and put it on a cart, but that seems less permanent.

I wasn't sure if I should have him install something on the wall that changes the intake direction, or make a tall version of what Alex has. Correct me if you disagree, but I think I should do the tall version of Alex's table, so I can move it in front when I watch or listen to something, and take it away when not needing the quiet. Should I have him put some kind of foam or rubber around to edge that meets the wall to make it more sound proof? Also, should I have him put the sound proofing, lets say Roxul board between the 2X4 plank (I'm assuming) skeleton, or should I have him put wood boards behind the soundproofing? Is a skeleton like the table with soundproofing enough? Like I said, I think it should stand on the floor so I can move it when not needed. Does anyone think I should have another design?

As for the fan: It could be off center or the belt of center or something, but I don't know how to check for that. I could see if the repair guy could check for it, or if he has a friend that could check for it, or could ask the landlord to, but remember that it is not a mechanical sound it is the sound of the air that is so loud; it could be off center or something causing the air to go in a noisier way, but it's not a noisy motor. If I put a cushion over the grill for a bit (where the air holds it) the sound is greatly diminished.

I'll ask the landlord to take a look. I haven't asked the repair guy to do anything yet, so if there are any specific suggestions like Roxul board get them in now. Ironically heater weather is leaving us, and I don't have my surround system up fully yet, but it's getting there.