VIVOSUN 4 Inch Inline Duct Fan 100 CFM, HVAC Exhaust Ventilation Fan with Low Noise for Basements, Bathrooms, Kitchens and Attics, Silver

Works well. Tight fit on 6” pipe but does fit. Simple to use. Good price.

Works perfectly, super quiet.

Installed over a register in a 2nd floor bedroom with poor airflow. I have it plugged into a temperature control switch. It's noisy but a little less than the last one without a speed control. The speed control is not real effective on this fan as I would like to slow it down a little more. With that said,I might return and try another one!

Excellent fan. The motor is not too loud. It pushes great airflow. It's all metal construction and proven fan technology Ensure it will work for years to come.

At only 100 CFM, this fan isn't too bad. If 100 CFM is what you need. I was expecting more from the design, I guess. With adding an 8 gig video card to my recent computer build, the temps on my chip cooler sky rocket to around 104°F or 40°C on many games, from an average of around 82.4°F (28°C). Which isn't too bad really, but I want to add some filters for dust, & having 104°F pumping into the back room, makes it very hot on a summer day. So I searched around & found this, that I thought would be a solution. I figured it was better than a large Molex powered fan. What I wanted, was to remove the heat that the computer was pouring into the room, with a powerful fan & vent system. All of the air flow goes in the direction of the top vent, & out already. Now I want to pull it out of the room, to the window to the outside. The video card is loud enough on it's own (see review elsewhere), so adding filters to soften the sound, as well as a vent to pull the sound, should reduce it, along with the heat. I looked over Amazon & the net, & found this had the most "quiet sound". Quiet, being relative to the user, of course. Some reviews said it was loud (it is). As you can hear in the video, it is louder than the filtered & non filtered computer. Just to give you an idea. The computer has a twin active fan on the video card, A T-1 thermal tower for the CPU, a 120" side panel fan, & some case fans; on it's own it can be a little loud. Mostly it's the video card, as a simular tower build w/o the 8 gig video card can't be heard (see Black Ice Monster review). So, noise isn't winning any awards. The video is via my phone, not great, not bad. Gaming headset doesn't pick it up, as an FYI. The second & most important thing this Vivosun booster fan needs to do, is evacuate the heat from the computer, so that it doesn't enter the room. The third thing it needs to do (on this checklist), is keep the computer cool. Preferably below current temps, but with in an acceptable range, as long as it's evacuating the room. So far, it's doing #2 alright. Bottom line: With the computer filtered & shut; it will drop the temp about 1-2°C in about 2 minutes. With the side panel off, it will drop it 5°C in 1 minute. The mean running temp in spring: is 35°C (95°F) Under load 43°C (109°F) With the fan off the computer has reached 52°C (125°F) under load on a simple game (Little Nightmares), & the VivoSun brought it down to about 42°C in about 10 minutes. Outside it was around 82°F, the room about 75°F with a pole fan running. So it does alright, just not great. It runs helps at about 5°C on average, but it does evacuate the heat to the outdoors for the most part. I can't say if the 240 CFM fan will do any better as I'm afraid it will be much louder. It's not horrible, just not quiet It sounds like an A/C unit. Oh yeah, it has a tick now after intermittent use in three months. I don't run the vivo fan when just doing text or surfing, only when gaming or doing 3D stuff. Also, the power cord is plenty long great job !! I have it on a wireless remote so I just click & on.

Works great. I’ve bought several of these. One failed after several months of 24/7 use, but the others have been running 24/7 for over a year with no issues.

The product doesn’t move near the advertised rating. You can move more air with your lips wrapped around a straw.

I don't care about plastic housings and I'm happy to wire my own switches where relevant, so for me and the applications for which I use fans (in this case, cooling inside my truck/paired with optional swamp cooler water flow), this is awesome bang for my buck. It's a bit loud but I don't care, that's to be expected when going for something with high airflow. I do wish I'd considered getting a couple of different sizes because this is actually more powerful than I need for its current use, but that's fine, sooner or later I'll move it and the attached swamp cooler setup I built to a different larger space and build a new smaller one for my truck. I'd much rather overengineer something than have it be insufficient (like my first pitiful swamp cooler attempt with computer case fans -- fun starter project to learn about wiring in series and wiring a three-prong switch, but totally inadequate for cooling the inside of a Ford Explorer!). So yeah, can't speak to how good this is for actual use in ducts, but as a cheap powerful basic fan for a DIYer doing something fan-related, it's a great buy and I'm thrilled I got it. The only way it could be more perfect would be if it had an on/off switch already integrated into the power cord, but that's not a big deal and of course it's not like it advertised/implied that it would have one. It's exactly what I expected, except more powerful. Everything about it seems solidly made and I anticipate it'll last a very long time. I'll most likely buy from this same manufacturer again in the future when I need fans of other sizes.

Works and fits as expected. Installed in mechanical room to exhaust the excessive heat. Not too noisy.

The fan encasement is made from a duct-like material, but it is much stronger and more rigid. The fan has plenty of room inside the ducting should the encasing ever be dented or deform from mishandling or falling. When I received it, it would rumble loudly throughout the ducting; the issue had something to do with the seating of the fan blade, because I took it off and ran it and the motor itself was silent. I removed the fan blade, applied some oil, and pressed in the blade while tightening the nut which holds it on -- the rumble was reduced significantly. Overall, an excellent fan exhaust fan at a solid price. Any workshop, growery, or perhaps a smoking room could benefit from this addition greatly., especially with the addition of a carbon filter.

Desde que lo instale, m problema de ventilación quedó resuelto, muy buen servicio hasta la fecha.

A marca e o produto em si são muito bons, porém veio mal embalado e chegou avariado, com as paredes laterais tortas e pagando na hélice, precisei arrumar antes de usar.

This is a very well built fan unit with quite a hefty motor in it well protected from any smoke, oil, or debris that may be channeling through with the exhaust. There is no switch, it's just a straight 6ft cord, but nice and heavy. It is very quiet, nothing lose, no rattling, and you can barely hear the motor. If you are wondering how much push is 100cfm its not a forceful stream but a steady noticeable flow about the same as a computer fan (60-100cfm) or one of those small fans you might have on your desk (ie it won't blow stuff off your desk). Great price, fast delivery, plenty of air and nice and quiet.. all around a good deal. I'm using it for a range hood and its perfect Thanks