Like many people, I’m working from home most days now, and that comes with the benefits and drawbacks of where I live. My apartment building was built in the 1930s and like most Chicago buildings, it doesn’t have air conditioning. I’ve purchased two air conditioning units – one for my bedroom and one for my home office – and from May through September they’re running whenever I’m in either room. However, as the 1930s was not known for its energy efficiency, even with the AC on high, it still often struggles to cool a room with a person, two computers, and some network equipment. If the temperature outside is above 75, the temperature inside is at least 82. My apartment is always at least 3-5 degrees hotter than outside during daylight hours. And I am definitely a cold weather person.
I’ve looked into numerous solutions, from buying a bigger/more powerful AC unit, to buying those tiny swamp coolers, to strapping blocks of ice to my chest (I actually have wrapped up ice packs in towels and used them when it was above 90 in my office). I want a solution that doesn’t cost a lot, wouldn’t cost a ton in power to run, and is effective at cooling. One of the things I kept seeing was NASA astronaut systems, which are tiny refrigerators that circulate cold liquids/gases around your body to cool you down.
While I was searching, it just so happens that Adam Savage of Mythbusters posted a video in which he builds a rig designed to keep him cool while he wears costumes at conventions. I watched the entire video and learned a lot about how refrigerators work, but most of his equipment is expensive, custom one-off pieces produced specially for him or not readily available to the public. So, I turned to another one of my YouTube regular watches, JayzTwoCents, who builds custom computers and does hardware reviews. He also has a lot of resources on water cooling computers. I decided to take some notes and build a water-cooling rig for HUMANS!
I bought a bunch of low-cost components which included a water-radiator (I already have extra fans so I didn’t need those), tubing, a pump, a reservoir to keep fill/empty from, specially treated cooling fluid (distilled water with chemicals added to keep gross bacterial from growing or metal from corroding) and a heat sink to pull the heat from my body. I tested with a small loop and tap water, and I noted that the heat sink seemed to be getting colder. I then replaced the tubing with longer ones, filled the cooling fluid, and spent about 2 hours lifting the tubes, lowering the tubes, shaking the tubes, and trying to get all the air out of them! When I was done, I left it running in my bathtub for a good few hours and confirmed it wasn’t leaking before moving it to my office. Then began the human trials!
I can’t say for certain as I wasn’t monitoring the temperature of the water/heat sink, but when turning on the cooler, there is an immediate and noticeable drop in temperature of the cooling block. It’s not so cold that you’re going to get frostbite, but it’s pleasantly cool. My current way of using it is to stick it just below my neck, and drape the tubes behind me, which isn’t the most comfortable but when dealing with 85+ degrees, I’ll take what I can get. Additionally, having a squared, nearly solid piece of aluminum on your chest (I tried to keep it on the back of my neck, but that’s even less comfortable) is not the most comfortable thing, so I’m planning on trying to file down the edges to be more rounded. I’m also investigating whether I want to replace some of the cooling with copper or aluminum tubing (copper will be cheaper and easier to get, aluminum has less corrosion potential) to make more skin contact and increase cooling. My original design featured a shirt with plastic tubing sewn into it in a giant spiral, but ultimately the plastic tubing doesn’t work very well at transferring heat, and I don’t think a single shirt I wear on multiple 90+ degree days with difficult to remove tubing will be the best long-term solution.
Here’s a photo of it during a test (I also need to find a way to not have it be a giant pile of parts and tubing).
I’m still experimenting, but in the meantime, let me also give you one piece of non-high tech that also works Cooling Cloths! These are microfiber, but I’ve also used cotton. You just soak it in cool/cold water and wrap it around your neck/head/wrists, and it cools you down (provided the humidity isn’t too high).
Stay cool, everyone!