I recently stayed in an apartment that didnt have central air so I created a corsi-rosenthal box since the smoke from the Canadian wildfires were so bad.

After 30 days of continuous use, with very minimal periods of it being turned off, this is what the filters look like!

It’s disgusting yet also so satisfying to see the filters get darker from debris, dust, and dirt.

Edit: typos

      • baldingpudenda@lemmy.world
        0·
        20 天前

        I got MERV 13 filters to help with my kids allergies. Inside the house, perfectly fine, but once outside it’s sneezing and runny noses. It’s amazing.

          • baldingpudenda@lemmy.world
            0·
            19 天前

            I looked up a 20 inch box fan on Amazon and it was rated for 67 watts. I ran it almost 24 hrs a day(kids loved to mess with it) and didn’t notice it on my bill.

              • Nollij@sopuli.xyzEnglish
                1·
                19 天前

                Watts per hour isn’t a thing. Watts is already a measurement of rate. 67 watts, running for 24 hours, is 1.608 kilowatt-hours.

                The rest of your math checks out, assuming no hidden “distribution” or “transmission” fees (like I have).

    • Korhaka@sopuli.xyzEnglish
      0·
      20 天前

      Been aware of the general idea for a long time, but had no idea that strapping HEPA filters to a fan has a fancy name.

      • Diurnambule@jlai.lu
        0·
        19 天前

        You have to cut some cardboard and use tape too. After when your solution beat every commercial solution you are allowed to name it, just to be able to shame corpo easily.

        • atlas@sh.itjust.works
          0·
          18 天前

          from huppakke:

          Someone posted a link to Wikipedia in the comments, came across their names:

          Richard Corsi, an environmental engineer and the incoming Dean of Engineering at the University of California, Davis

          Jim Rosenthal, the CEO of filter manufacturer Tex-Air Filters

          take what you will from this, but it’s definitely not a stick-it-to-the-corp kinda thing

          • Diurnambule@jlai.lu
            1·
            18 天前

            Yeah I was trying a joke. It still beat commercial alternatives which I fell is a Second good reason to give it a name.

  • Captain Aggravated@sh.itjust.worksEnglish
    2·
    20 天前

    “Corsi-Rosenthal Box” sounds like it’s some theoretical physics thought experiment, but no it’s some filters and a box fan.

    Be tempted to build one of those for my shop.

  • billwashere@lemmy.worldEnglish
    1·
    19 天前

    I totally did not realize how much real science was behind these things. I mean this design is so simple and obvious, it seems like something I would throw together because it just looks like it “should” work. And according to the research I just read they are very efficient and effective. Super cool!!!

  • renrenPDX@lemmy.world
    0·
    18 天前

    These are great, but if you’re looking for something slightly less bulky, there’s a dude selling kits online using pc fans. I’ve got two and they’re pretty much a CR box in its final form. Kits come with laser cut panels, fans, grates, etc. only need to supply two filters. Way quieter than a box fan. They’re a bit pricey but worth since they can pretty much be placed anywhere.

    google clean air kits.

    • ZoopZeZoop@lemmy.world
      1·
      18 天前

      For that money, you can buy actual air filtration units. The box fan may be noisy, but something that big is going to have massive surface area and provide a lot of filtration.

    • Imgonnatrythis@sh.itjust.works
      0·
      18 天前

      Curious why it’s not 5 filters with some little toilet paper tubes or something for legs. Was it found that the fifth filter is diminishing returns?