VIVOSUN Z4 4 Inch Inline Duct Fan, 203 CFM Ventilation Fan with Variable Speed Controller for Grow Tent, Indoor Garden Ventilation, Black

Very quiet and reliable! The speed control is icing on the cake because even more-expensive fans seldom have that option. This fan was actually cheaper than a similar Chinese-made blower that I bought months ago, but this one is MUCH better made. This one it is replacing was too loud, and after just a week started rattling and making out-of-balance noises that only improved slightly when I tightened things up. Not the Vivosun fan! This thing has now been in service just as long as the old one, and it still sounds and moves air like it was brand new. I very much feel comfortable comparing its performance to that of a Hurricane fan (one of which I also own). These things are perfect for building stand-alone air filter/charcoal filter boxes. My whole family has allergies, and teamed with the right filters this thing is keeping my family sniffle-free without all the noise of a HEPA filter.

We had a 2nd floor room in our century-old house that had only a faint breeze coming from its vent via 6" flexible duct tube that was routed down through an old chimney to the basement where there was only a short distance between the main duct from the furnace/HVAC and the hole in the chimney. Consequently, longer inline fans were not an option. After installing the Vivosun 6" fan, that previously hot-in-the-summer and cold-in-the-winter room now has the best airflow in the house-- even airflow overkill for just one room. The variable speed controller on the fan allows you to adjust from super fast all the way down to very fast. Yeah, it won't blow slowly. This fan is no wimp! The fan is well balanced and lubricated and runs very quietly. About the only noise is from the wind that the fan creates, which is to be expected and is unavoidable. The motor itself is just about silent. UPDATE: January 15, 2020. After using it for a year and a half, it started to squeak and then make a rubbing sound. I contacted Vivosun and asked if there were any lubricants that they recommended or would advise against. They refunded my purchase price (!) and said that purchasing a new one from Amazon would be faster than servicing it. This is well past any warranty time and WAY ABOVE AND BEYOND any expected customer service! Excellent service!

I received the fan and canister and was happy with the build quality and performance. Happy with my purchase. However seven months later the fan begin to make grinding and rattling sounds (still worked but very loud), it sounds like the bearings have gone bad. That said I reached out to the company with the issue and they were responsive and within a week (after some communication and sharing of videos of the issue) they offered a great resolution. Due to the size of the unit a return via mail didn't make sense for the vendor or myself. They suggested a refund on the cost of the fan portion of the kit, and did not require a return of the original unit. IMO I received good service and am happy with the resolution. So why four stars? Well I was happy with the unit prior to the presumed bearing issue, and I had a good customer service experience. So I'm giving VIVOSUN the benefit of the doubt since faulty products can happen.

i used this for dozens of different applications including funneling large amounts of hot air, venting toxic fumes, a window fan in the summer, and now i use it for an air filtration box. Ive had this thing for over a year and its an incredibly versatile tool. easily gets a 5 star! im planning an upgrade of the speed dial to see if i can get it to spin slower on the lowest setting. I also want to take it apart and inspect the bearing and see it it can be replaced. although it works fine and isnt that loud so i haven't yet. i just think if its an easy swap that it would make a big difference. definitely an extremely durable product and im very very happy with it. as for performance; it moves a ton of air. its not loud and exceeded my expectations in how long it lasts without problems or breaking. still going strong and ive never had to repair it. it currently sits on a purpose built shelf in my home office attached to a 12"x12" filter box that you can buy at a hydroponics shop. i modified it to take a premium HEPA air filter and sealed it with air conditioning foam insulation adhesive strips. It can filter the whole rooms volume of air in about a minute at full speed and i use it every day on the low setting for hours at a time. it definitely beats the heck out of those air purifiers you can buy at hardware stores which are just over engineered pieces of plastic with weak fans and an air filter. it didn't come with a stand.

Been running a full year, nonstop, at about medium speed, zero problems. I have done no maintenance. It moves a lot of air. It's kind of loud, but I can't compare loudness to other fans of the same size. When it was in my living room it was too loud. It's in my bedroom now not far from my bed and that doesn't bother me. I am mining in a grow tent in a small 1br apartment and this ventilation solution has allowed me to max out my apartment electrical grid and keep quite an oversized (for my living situation) mining operation going. I have a smaller intake fan by the same brand, a different model, and with the two fans I circulate the outside air through my tent (both intake and exhaust tubes hang out the window), so that it does not affect the air pressure in my apartment. It was really drafty when I was either sucking air in, or blowing it out. I thought I was getting the Korean Fan Death, my mouth would be soooooooo dried out every morning because my bedroom had like low air pressure. So keep in mind if you are exhausting hot air outdoors, that creates an air pressure gradient with other impacts. I built an audio dampening box out of foam and wood to enclose the tent with the fan in it, and it helped, but was only maybe necessary. Hope this helps!

Product works as described. I used it in my basement to direct marijuana smoke outside through some 6" dryer tubing, which is merged into my dryer exhaust. This keeps my basement and house smoke/odour-free. I cannot predict how long it will last with marijuana smoke residue blowing through the fan blades etc, but for the money, it is well worth it. The fan is quiet itself, but with the fan mounted to a joist in the basement ceiling, the floor above it rumbles like crazy. There is a dial to adjust the fan speed.

I needed a venting solution, and this has more than completed the task. It was a little noisy until I connected the vents but is now acceptable and doing a great job at keeping my computer cabinet cooled. I wish I had bought this months ago! Airflow is better than expected, even though I have HEPA air filtration on the intake to the inclosure. Beats many other solutions I have tested!!

Très performant , le filtre à charbon est très efficace et la ventilation tres puissante , le variateur intégré est très utile pour ralentir la rotation du fan . Il évacue la chaleur rapidement pas besoin obligatoirement de “in “pour une tente inférieur à 4x4 la ventilation en passif suffis . Concernant le bruit c’ est très discret si vous utiliser simplement une gaine isolé de 6” à la sortis du fan . pour une meilleure performance mettre directement le filtre à charbon à l’entree du fan si vous avez de la place dans votre espace .

Passt, hat eine brauchbare Druckdifferenz um eine Hephafilter davor oder dahinter zu schalten. Geräuschentwickung angenehm und angemessen! Preis sehr gut. Habe damit einen Werkstattfilter gebaut.

Loud but it works great for temperature control and removes odor quite nicely. I bought a 2nd unit as I have two spaces. The 1st unit has been running continuous for at least 10months. This unit SUCKS in a good way : )