Wathai 12038 120mm x 38mm 5300rpm High Airflow 12V 4pin FG PWM DC Brushless Cooling Fan

Update: I've now had 3 of these fans fail in the same way only a few hundred hours after being put into service. They will fail to reach full speed and start making a noise. Eventually they will jam completely. After dissecting all 3 I found a failed capacitor can jammed between the rotor and the stator coils. Removing the can and reassembling (without replacing the capacitor) the fans will work at partial speed but not the full 5300 RPM. I'm reducing my rating to 1 star as these fans are NOT reliable and will fail prematurely regardless of the operating conditions. Whether it's a bad batch of capacitors or a bad design, I can't say, but a failed capacitor causing mechanical failure of the fan after only a few hours in service is unacceptable. Original review: I have a small single room ventilation system which was previously using Noctua industrial 3000 RPM fans. I bought two of these to try as upgrades, one for intake and one for exhaust in an HRV type setup. The exhaust fan seems OK after 2 weeks, but the intake (installed in a bottom to top airflow configuration taking outside air in via a filter) started making awful noises after about 48 hours and seized altogether after 3 days. I removed it and got it spinning again on its edge, reinstalled it, and within 2 hours it seized again. It’s seen air temperatures between about -2C and 10C, and would see a range from -35C to about 40C in that installed position, which the Noctua Industrial fan has handled just fine for over 2 years. So I’m rather disappointed, to say the least. I tried replacing the lubricant with some multigrade oil to see if this will help. As I said, the performance is exciting, but I can’t really stomach the prospect reliability issues in this system.

Amazing air output and noise level! I found operating it at a low 3-6 watts, it is moving as much air as most of my other 120mm fans. Crank it up to full power of 20+ watts and it's like facing a 30+ mph headwind. Thankfully I purchased a speed control to go with this. Unless you are mounting this fan inside a sound proof chamber you'll definitely need one to restrain the noise. I purchased this fan for cooling under my tractor canopy so the noise isn't that bad compared with the tractor diesel engine spinning 2500rpm. Most of the time I'm using the speed control at about 1/2 of maximum. But it's wonderful to crank it up when the outside temps are getting high. Size is correct match for 120mm mounting. The speed control I used is 4 pin version so fan connected right up. I haven't had any problems with operation. Get a speed control that permits setting a minimum speed also helps. Overall I am very, very pleased. I've bought several other Wathai fans and this one is just as well built as the others. I will definitely to buy Wathai fans.

In accurate size - it’s actually 92-93mm not 120

Okay, so, I've been using this thing for about a year and here are my thoughts. In order to use this, I bought a barrel-jack/fan connector and an adjustable fan controller that fits said barrel jack connector. Upon opening the box the first thing that you notice is the sheer girth of this unit. I mean, it feels much heavier than it should. The build quality is amazing and it runs like a top. at low speed its nearly silent and cools my mid-tower cpu case and heat-sink to a comfy 45c. I want whoever reads this to understand, I don't have a fan on my cpu heat-sink, this thing is connected to the front inside top of my case so as to suck fresh air in and blow it. It blows enough air, from that position to not only cool my heat-sink on its LOWEST setting but to also hit the fan in the back of the case. On medium, the fan sounds like what I imagine a duck hitting a airplanes turbine hears before it becomes meat shrapnel. It's just, Incredibly loud. Like, you can hear it 30+ feet away at half speed. The cooling performance though, matches the noise. I'm able to drop from 71c post Vulcan shader render to 42c in 20 seconds at half speed. Now comes the complicated part. Depending on the heatsink you use, There's little to no point in using this thing past half speed. Let me explain. The heatink can only throw so much heat, and this fan moves air so fast, after half speed, it reaches a point where it just doesn't remove any more. I am able to hold a paper towel to a wall at 3 feet from the back of my case at the fans full speed though lmao. Bottom line is, It's stupid, overkill, and I'm in love, buy three. Just don't forget the adapter and external fan controller, this may kill your power supply.

Me and my friend bought several of Wathai fans for kids science project. Work reliably and efficiently. Our only issue was we were not able to find a 120mm fan in 2 wire configuration (only 4 wires but we do not have a circuit to control pwm). With the 4 wire version we get the necessary air-flow/ weight needed for our project but cannot control speed/ slow down based on supply voltage. With change in voltage there is feedback within the fan to compensate and we cannot slow down. If you have a fan in 2 wire prototype version, we can test it.