• Derek

Build Your Own Air Purifier!

Updated: May 7, 2019



This is a very simple, yet effective “Do It Yourself” air purifier you can make for about $40 (45,000 won). The capacity is good enough for a medium-sized Korean bedroom up to about 20-23 square meters (6 to 7 Pyung). Anyone can make it, as it’s literally just a fan sitting on top of the filter itself. There is also now a 3D printable bracket and fan blade cover available, if you can hash-out the Korean HERE.


*This is a Do-It-Yourself device you make, so you accept any and all responsibility for any problems that may result the from the making of or the use of it, such as being electrified in a long, slow painful way, fire resulting from fan failure killing every member of your family and 200 people in your building, a child's fingers getting mangled beyond bloody recognition in the fan, etc. Wiring is something you need to have knowledge about, and be safe with.

I use a hot glue gun to attach the fan to the filter. Tear off filter after 6 months of use, pick away residual glue, change filter, and re-glue.

The only real work required is to wire the plug to the fan. I will link to a video I made explaining how to do this, but you can purchase a pre-wired cord and switch, so you do not even have to wire the switch. You will, however, need to solder the wires together, or twist the opposite leads to the proper side on the power switch cable, and safely cover with a wire nut or electrical tape. This is the only part that requires some simple knowledge of how electricity works, so please make sure you understand this part, or ask someone for help. We don’t want a terrible shock, or to start a fire! Here is a video showing the basics of wiring the cable and a switch, if you buy a plain cable and want to add a switch, later. The filter is a Xiaomi HEPA filter. You can get them with or without the charcoal insert to help fight against VOCs (it’s cheaper without). Prices on the new Xiaomi filters run around $30 to $35 (33,000 to 36,000), depending on the maker and if it has the VOC charcoal insert. Order the Xiaomi M1R-FLP or MCR-FLG. The green will work too, but it restricts the air a bit more due to smaller hole size. DIY Air Purifier Parts list:


1. Xiaomi M1R-FLP or MCR-FLG Filter (Use Smilefilter or Hankuk Filter brands to save)

2. Windy MV-20PN Fan (get the larger MV-20PN, not the 15)

3. 220v Power Cable with Switch 전원 코드 2m 화이트 전기 220V 중간 스위치

4. Solder and/or electrical tape to safely splice the wires together, and cover.


Here is a video of it working in a 7-pyung efficiency home:




There is currently a 3D printed connector piece and top which has been created by a Korean builder, but we are not able to get the file, so we are making our own. I also hope to develop a version with a more powerful fan for up to 18 pyung spaces.


A 5-Pyung version with a lower power usage


Anyone can build this, and have a working solution for a small room. Takes 15 to 20 minutes. New cheaper and more efficient idea that really works. I found that a KV150 fan fits into a Smilefilter brand Xiaomi filter (or a Hankuk filter brand, but it's quite snug), if you buy it for 15,000 won, sans VOC charcoal insert. The purple filter adds anti-microbial and possibly charcoal for anti-VOC, depending on brand. I now avoid the green xiaomi filters and equivalents, only because the extra charcoal insert will not fit with this model. If I add some cheap Diaso chair leg felt along the edge of the fan, and snipped of one little plastic piece on the fan, it is a snug fit -- snug enough that I can lift it by the fan, and the filter stays on. Blows almost as much air as the large fan (or similar -- need side-by-side comparison, next week), with less wattage, because there is no blockage of the air flow.



Remove fan clip. Add felt. Fan slides snugly into filter. Wire plug. Done.

This is a 30,000 won solution that will work very well in a 4 to 5 pyung room for 6 months before filter change! Just need to find a way to cover the fan on top! QUIET SOUND, and just 12 watts! That's just sipping power. Two could be used in a large bedroom, or to cover about 10 pyung at just 24 watts (less power than many lightbulbs). Five could cover an 18-pyung home. These designs still need a cover on the top, for young child finger safety. You could glue-gun the filter to the fan, after inserting, to make it not come out until you ripped it out after it needs a new filter, but this version stays very snug, as is. Fan can still be used again. Should work with any Xiaomi filter, so long as you don't have the charcoal VOC insert. I find the blue or purple Xiaomi filters are best.



Parts needed, for anyone interested (I hope to find small ways to improve, later, like a top cover):


V-150 fan: http://item.gmarket.co.kr/DetailView/Item.asp?goodscode=1318053104&GoodsSale=Y&jaehuid=200002673 2. Xiaomi blue filter (no charcoal insert -- go purple, but avoid green due to sizing, for specs) by Smilefilter or Hankuk Filter: http://item.gmarket.co.kr/DetailView/Item.asp?goodscode=1563748490&GoodsSale=Y&jaehuid=200002673 3. 220v cord with switch already added: http://item.gmarket.co.kr/DetailView/Item.asp?goodscode=1437779523&GoodsSale=Y&jaehuid=200002673 4. A4 Sheet of sticky-back chair leg felt from Daiso, cut into strips.



Smaller DIY model for 5 Pyung:


Here is another video of the first purifier that I made, showing how to do it. I consider this purifier useful for about a 5 pyung space. I have had students make these as part of a class project. You might come up with your own designs, using your own box style. Again, this is a DIY device you make, so you accept any and all responsibility for any problems that may result the from the making of or the use of it, such as being electrified, fire, a child's fingers in the fan, etc. Wiring is something you need to have knowledge about, as there are dangers involved, just as with any product you make involving electricity. The key is to remember that there needs to be an air seal to keep dirty air from seeping into the box -- don't allow open gaps or loose edges where air can bypass the flow through the filter. Please feel free to contact me, if you have any questions. Some people have modified this design to do great things, like make their own portable air purifier for hotel trips!