VIVOSUN D4 4 Inch 195 CFM Inline Duct Ventilation Fan, HVAC Vent Blower for Grow Tent, Attic, Basements or Kitchen, Hydroponics Exhaust Booster Fan

This is a solid fan. The last one I bought had good air flow, was reasonably quiet and lasted 5 years. Not a fancy option but solid and I just bought my second one.

In making this next generation gaming computer, with an 8 gig Radeon video card among other things, the blowing or ambient heat from the computer is enough to heat a small room. I can & have used it in the winter to do that. Well, I was running something, & it was on over night. In the summer, I want to expel this heat so I can stand to be in there, gaming. Trying to get the right CFM to noise ratio can be difficult in a computer environment, in a small room. Mainly home based. This extractor from VivoSun is a great one. It's not quiet, & sometimes I can't wait to turn it off, but it pulls out the heat like I want it to, well, enough to keep the temps nice. Generally, the CPU's radiator will get up to about 107°F-113°F (42-45°C ) with this 195 CFM fan bringing it to (32°C-37°C) 89.6°F-98.6°F & it's pulling most of that heat out the window. I included a snap of some general video editing temps with out the VivoSun, & the bottom one is after it got going. The temps dropped in about a minute, which is super fast! When I "forget" to turn it on, & the computer gets up to about 45°C, it takes the exhaust about eight odd minutes to bring it down to 35°C & about a full 10 minutes to level off at 33°F. So that's not bad really. I have tried a small CFM unit (106 CFM), but the pull just wasn't there. I have included a video so you can hear how it sounds. Of course, it's muffled a bit, being I captured it from my phone, & recordings always sound different than your ear. If I can, I'll try to include a video of the room's cooling turbo fan so you can hear them both. Not bad, but not whisper quiet. They don't claim to be, either, so nothing on them. If I bring the tower down to the floor, or move it away, that will change things a whole bunch. If you're thinking about adding an external cooler to your gaming/video unit, I strongly suggest VivoSun. The product works great, & they are on top of any blips you may have. In fact, they helped me upgrade to this unit with a matter of an e-mail. That's AWESOMENESS to the 10th! Now I don't have to "worry" about leaving the computer on for a bit while I'm in the middle of a game, or when I step away for a moment. I know that this exhaust fan is going to keep the system cool. Bottom line, this exhaust fan works very well sealed to my tower's top fan port. So much that I will be adding a smaller one to my 3D printer to better help regulate the temps in that case. I did need to purchase dryer duct (hose), & a 4" inlet pipe. The aluminum tape & clamps came with the dryer ducting. I used some sticky sound dampening on the I/O exit panel to better direct the air flow being pulled up & out. Also, it has holes in the "feet" for more secure mounting. I just hot glued it.

I really debated on four or five stars. I can't give it two stars since I'm using it as a bathroom fan (not it's intended purpose). I noticed the fan really chokes down if you restrict the inlet at all. But chokes less if you restrict the outlet, so I put my back draft door on the outlet. It is certainly quiet and has a much more pleasing tone than the $150 garbage bath fans you get from the depot.' This fan seems to be well constructed with good bearings, well balanced and the wired plug is a nice thing to have...... fits 4" duct reasonably well.... a great mounting bracket. In all, for MY purpose it's meh, but again, it's intended to be an HVAC fan so I can't give it too hard a time. The price is less than the depot fan and I still think it moves double the air of a depot fan, just not 200cfm in my application.

I purchased this inline fan after my Vevor inline fan was giving me issues for the second time. Instead of troubleshooting with them again, I decided to buy this and it’s so much better. I use it for my laser engraver and although there’s no on/off switch, the unit is not loud and I could not smell any smoke whatsoever. Very happy with my purchase.

This is a really good fan to use for my homemade airbrush paint booth. Coupled with a dryer lint trap, it works like a charm. It moves a lot of air. I will say that the fan is a bit loud, but the acoustics of the box are likely amplifying it. Other than that, it's a great fan with a built-in speed controller.

I purchased this item twice. the first unit was only in service for a very few hours total over two years before the impeller fractured. I got another because it FITS the area I designed for it. There was absolutely no reason for the impeller to fracture except it was defective from day one.

Using this pump to evacuate resin fumes from a grow box, makes staying in the same room fine until the door is opened, so it must be enough to create negative pressure for a 2x3x4ft cube. Not very loud, about as loud as a box fan on medium. Overall ticks all the boxes I needed, been running 24/7 for a few weeks now.

Had this fan for a month or so and enjoy the performance. Moves a good amount of air without being too loud. Works great in my 4x2.