How noisy is this attic fan- or recommend a quiet one.

[Malcolm Schweizer]

I'm posting here and not in workshops because my question is specifically about the noise of the attic fan. Does anyone have this model? What if I put a layer of carbon fiber on the blades so they don't flex or buzz? I'm limited to 16" diameter for this application, so a belt driven whole house fan won't work. This is more about creating a breeze through the house with dust management an added benefit. I'm making an exhaust fan in my shop and two of these side by side would perfectly fit.

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[Mel Fulks]

The box certainly looks like the one I installed in attic. It was loud even used like that ,so I boxed it and installed some insulation to get it quiter. It's a "high velocity "fan. You might be better of with something quieter

[Roger Feeley]

We installed two of these. They don't move a lot of air but do cool the house.
https://quietcoolsystems.com/
YouTube have to stand under them to tell if they are running. Even then you have to listen carefully.

[Bruce Page]

Malcolm, why not post a direct link to the fan?

[Mel Fulks]

The old Vornado fans were highly prized ,quiet, moved a lot of air. Haven't owned a newer one but they get good reviews.

[Malcolm Schweizer]

The box certainly looks like the one I installed in attic. It was loud even used like that ,so I boxed it and installed some insulation to get it quiter. It's a "high velocity "fan. You might be better of with something quieter

Thanks- it looks like the metal blades would be loud.

We installed two of these. They don't move a lot of air but do cool the house.
https://quietcoolsystems.com/
YouTube have to stand under them to tell if they are running. Even then you have to listen carefully.

Thanks- I will check those out. Their marketing on their website is a little exaggerated. They claim it will revolutionize my life. Wow- just by getting a fan? Haha. It looks like you have to use ductwork, which won't work for my application.

Malcolm, why not post a direct link to the fan?

It is on eBay and SMC has a rule about not linking to eBay.

[Bruce Page]

It is on eBay and SMC has a rule about not linking to eBay.

Good reason. Thanks.

[Mel Fulks]

I think it's Air Vent 53315

[Malcolm Schweizer]

The old Vornado fans were highly prized ,quiet, moved a lot of air. Haven't owned a newer one but they get good reviews.

At 293 CFM I would need 4 to achieve my goal of >1000 CFM. I could lower my goal some, but not sure these would do. I have seen them, and they are very quiet. I could fit 3 of them over the 34" wide door for 879 CFM. My downstairs is about 1200 sf with 10' ceilings, so 12000 CF. Well, it's worth considering, but might be too small.

[Malcolm Schweizer]

I think it's Air Vent 53315

Yes. That's the one. Sorry, I thought it said that in the description. I was mistaken.

[Mike Henderson]

We installed two of these. They don't move a lot of air but do cool the house.
https://quietcoolsystems.com/
YouTube have to stand under them to tell if they are running. Even then you have to listen carefully.

I have two of these in my house. One is in the hallway outside my bedroom. My wife says it's too loud at night and disturbs her sleep (I'm hearing impaired so I don't hear it). I use the one further away in the house at night.

Their claims of being as quiet as an air conditioner are not true - it's significantly noisier.

The noise is all air movement noise, not fan noise. The motor and fan are pretty quiet but the overall system is noisy.

Mike

[Malcolm Schweizer]

I have two of these in my house. One is in the hallway outside my bedroom. My wife says it's too loud at night and disturbs her sleep (I'm hearing impaired so I don't hear it). I use the one further away in the house at night.

Their claims of being as quiet as an air conditioner are not true - it's significantly noisier.

The noise is all air movement noise, not fan noise. The motor and fan are pretty quiet but the overall system is noisy.

Mike

Yes, I see they say 59db, which isn't just all that quiet.

[Michael Dye]

Malcolm, just remember that the more fan blades and less rpm you turn the fan, the quieter it will be. As an aeronautical engineer, I saw this firsthand. Look at most of the commercial turbo-prop high capacity aircraft and they are ultra-quiet. The example you posted probably won't help you much as it is listed with a two bladed fan, yet a 6 bladed fan is pictured. You might want to call the manufacturer. Also, look at some of the new high efficiency A/C condensers. Many use an 825 rpm motor with 3 and 4 blade scimitar style fans. Super quiet yet they move an awful lot of air.

[Roger Feeley]

Yes, I see they say 59db, which isn't just all that quiet.

Hmmm... Ours were so quiet that we sometimes didn't realize they were on. The noise suppression comes from the fact that the fan itself isn't mounted in your ceiling. There is a flexible duct and the fan is suspended from the roof joists. In my case, I took some pains in mounting.

1. I made sure that there was a nice curve in the flexible duct so that there was no straight line between the fan and the opening. The noise would have to make that turn and (I reasoned) would be mostly absorbed by the soft material.
2. I can't remember exactly what I did but I isolated the fan from the wood rafters using some sort of soft mounting. I think I found some sort of rubber motor mounts. Then I used plastic plumbers strapping instead of metal or wood for the support. I remember thinking that rubber bungee cords would be better but I didn't think they would last. The whole idea was to not turn my roof into a sounding board.

We had two. One was in the master and one in the hall. All anyone could hear was a low rumble. Of course this was probably 8 or 10 years ago. Their current product could be noisier. When we sold our house a year ago, we had to instruct the agent to check the fans to make sure they were off after showings.

I was going to amend my comment and suggest some sort of pilot light to indicated that the fans are on.

[Roger Feeley]

+1 on Michael's comment about blade speed and number of blades. I've installed a number of attic fans and the ones that mount in your ceiling are very different. Generally, the direct drive ones that run at high speed are like Lear Jets. The ones with pulleys run at lower speeds, have more blades and a higher pitch are much quieter.

This would be a pretty good application for a variable speed motor. You start it up on high before you go to bed and then slow it down overnight.