A Chinese tech creator named Electrolytic Sodium Carbonate (ESC) has designed a liquid-cooled PC system that, instead of using a standard PC-mounted radiator (that’s boring), is hooked up to a household air conditioning unit. The system in question features an Intel Core i9-13900K and RTX 4090, paired with a 12,000 BTU air conditioner to supercharge cooling, which even under stress testing, keeps the GPU running at just 20 degrees Celsius, which is around room temperature.

This isn’t the first time ESC has come up with a creative way to integrate powerful household air conditioning units with personal computer systems. Previously, they built a “whole house” liquid cooling system that appears to have five loops available for multiple PCs. That said, ESC believes this air conditioner-based cooling project is the “perfect companion” for an RTX 5090 system but is currently waiting for a compatible water block for their graphics card to begin testing.

A lot bigger than a 360mm cooler but also a lot more powerful

The air conditioning unit is the Xiaomi KFR-35GW, which boasts a quoted 12,000 BTU cooling capacity and typically consumes around 1.2kW. Measuring 765 x 268 x 550mm, it's significantly larger than the PC tower it's cooling – and much bigger than a standard 360mm PC radiator. But it's also far more powerful, and we'll get to that in a bit. The video also showcases the modification process for the Xiaomi KFR-35GW, which mainly involves welding and pipe management to integrate the liquid cooler reservoir inside the AC unit. And, of course, to make it look the part, there are some Intel, NVIDIA, and AMD branding stickers on it as well. With all that out of the way, the real question is: how well does it work?

After 40 minutes of hardcore stress testing using popular tools like FurMark and the AIDA System Stability Test, the CPU cores were only a couple of degrees hotter than their initial temperatures at the start of the test. As for the GPU, ESC moved the AC unit outdoors, where it would typically be installed, and before testing, the GPU temperature was just 2 degrees Celsius, with a 12-degree Celsius hotspot. Running stress tests again saw these temperatures rise to 20 and 36 degrees Celsius, respectively. That’s about the same, if not lower, than a normal PC's idle temperatures.

The “perfect companion” for the RTX 5090

We know that the RTX 5090 features an incredibly high 575W TDP—that's 125W more than the RTX 4090, which means that it's going to generate a lot of heat. To add to that, recently published reviews indicate that not only will the RTX 5090 run hot, but it will also direct all that heat straight toward the CPU socket, causing a significant rise in CPU temperatures.

So, it's no surprise that a beefy cooling solution is necessary to keep temperatures in check, and this air conditioning unit seems to do the job. Of course, not everyone can just DIY a spare air conditioner into the world's best liquid cooler, but for those who can, it's both a creative and functional way to cool a PC. ESC even mentions in the video that this setup isn't just ready for an RTX 5090, it's prepared for an RTX 6090 as well.

About the Author

Hassam Nasir

Hassam boasts over seven years of professional experience as a dedicated PC hardware reviewer and writer.