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How does a water cooling fan work in a PC?

Views: 1     Author: Site Editor     Publish Time: 2022-11-10      Origin: Site

When building a PC, we know that there is generally air and water cooling in the choice of cooling, but those who have used water cooling should know that there is also a matching fan in the water cooling system. This article will look at the main force at the end of the cooling cycle: the fan.

Water cooling is actually can also be said to be air cooling. Water cools the parts. The air cools the water and foam-rinse-repeat. Once the pump delivers the coolant (and the heat that comes with it) to the radiator, the fan is needed to flow enough air over the heatsink to transfer the heat to the surrounding air.

liquid cooler fan

How Fans Work

Almost all of the fans we use in PCs are axial flow fans. They are so-called because they move air along their axis of rotation (the center of the fan). They are simple and very efficient and offer a wide range of design options that allow the fan to behave differently in different applications.

The fan design is a balancing exercise. Performance and noise levels are critical parts of fan design that concern consumers, and to date, no one has been able to make a perfect fan in both area.

The key to axial fan efficiency is the blades. Blade length, number, pitch, and shape together form the performance profile of a fan. The science of blade geometry is surprisingly involved and beyond the scope of this article, but if you delve into the science and math, you can learn more here.


Like radiators, water cooling blocks, and all other parts of the custom water cooling circuit, fans have different aspects of understanding and considering to ensure you get the results you want.

Sizing and Fit

Fans come in standard sizes, with 120 mm case fans being the most commonly used today. The 120mm measurement is the distance from one side of the fan body to the other. A typical 120mm fan has an actual blade diameter of 110mm and a mounting hole spacing of 105mm. 140mm case fans are also famous and are becoming more popular. Every major radiator manufacturer produces both sizes.

Like the cooler, this number describes only its two sizes, omitting the thickness entirely.

The standard thickness of most fans used in PC cooling is 25 mm. This applies to sizes as small as 80 mm and as large as 200 mm. Outside of that range, the thickness varies too much to name a standard.

The standard 25mm thickness is not nearly all that is available. 120mm thicknesses range from 12mm to 38mm, and other fan sizes can have different thicknesses.

So why the difference?

Thinner fans are used for applications with smaller clearances, such as small PCs. Thicker fans are typically used for more industrial applications.

Generally, the thinner the fan, the quieter it is, but the less airflow it produces. The geometry involved in a thinner fan limits its blades' spacing, which directly affects air movement. Thicker than standard fans provide excellent airflow while reducing noise levels.

Always consider thickness when checking its suitability for your design.

Remember to follow our website and blog if you are still interested in learning more about PC components. For custom computer fans and liquid coolers, contact a professional PC case manufacturer - Tecnomall.