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You could probably buy a box fan and tape a HEPA filter in front.
This is a really cool project but frankly you can do it a lot cheaper. Find the cheapest box fan you can find, and find the cheapest HEPA filter you can, and strap the HEPA filter to the front. To improve air purification even futher, slap an activated carbon filter on the front too, and your air purifier now filters VoCs! For cheap Activated Carbon Filters, look into the kind used for Aquarium filters. They'll work…
if you don't mind a noise you could buy a 2nd hand vacuum cleaner with a built-in hepa or water filter (ideally also with adjustable speed to make it less noisy) and just let it run without a hose, sucking the air and pushing it through the filter...
If you don't mind the noise and wasting a kilowatt on something that can be done with two dozen watts.
Earlier quoted context omitted.
This may or may not work, cheap box fans aren't designed to push/pull air through obstructions (ie: low static pressure) and HEPA filters are giant obstructions. So instead of the air going through the filter it'll go through gaps, around the edges of the blades, etc. I used a cheap box fan for some DIY ventilation and the loss in airflow is massive after filter and ducting.
couldn't you easily test this by sticking your hand (wet it first) in the middle section of the filter and see if you feel any air coming through
Do air purifiers really work? I always have impression they're just sham, or at least placebo.
I can vouch for their ability to detect impure air. If I start cooking anything, it switches on within seconds. It’ll turn on within about three minutes of sweeping the floor. And if the detectors can turn on when the air is dirty, it stands to reason that they can tell when the air is clean and they turn off as well.
Shortly after getting this, some intriguing news surfaced regarding the installation of air filters in a California school (due to a gas scare) which resulted in a jump in test scores vs other schools in the same district.
I am not a scientist, but I’m feeling pretty convinced about the efficacy of these things.
https://www.vox.com/2020/1/8/21051869/indoor-air-pollution-s... https://news.ycombinator.com/item?id=18219391
Earlier quoted context omitted.
> Because they are designed to be quiet and still provide good flow of air they produce almost no pressure differential to speak of and the flow can be halved by a wire mesh that is a bit too dense There are high static pressure fans which address this problem, specifically designed to work with pressure differential, usually used to blow air through radiators for water cooling. The fan linked in the github page (Noc…
> it provides a static pressure of 7.63 mmH2O If anyone else is wondering, that's about 0.8 mbar (roughly 8 ten-thousands of an atmosphere), or 80 Pa of over-pressure. To put this into perspective, my local atmospheric pressure varied about 2000 Pa in the last 48h due to weather changes.
This is a really cool project but frankly you can do it a lot cheaper. Find the cheapest box fan you can find, and find the cheapest HEPA filter you can, and strap the HEPA filter to the front. To improve air purification even futher, slap an activated carbon filter on the front too, and your air purifier now filters VoCs! For cheap Activated Carbon Filters, look into the kind used for Aquarium filters. They'll work…
This is a really cool project but frankly you can do it a lot cheaper. Find the cheapest box fan you can find, and find the cheapest HEPA filter you can, and strap the HEPA filter to the front. To improve air purification even futher, slap an activated carbon filter on the front too, and your air purifier now filters VoCs! For cheap Activated Carbon Filters, look into the kind used for Aquarium filters. They'll work…
Would something like this this work sufficiently well to capture airborne fur/dander from a tabby cat? Or will there be a vastly different outcome from an expensive one?
This is a really cool project but frankly you can do it a lot cheaper. Find the cheapest box fan you can find, and find the cheapest HEPA filter you can, and strap the HEPA filter to the front. To improve air purification even futher, slap an activated carbon filter on the front too, and your air purifier now filters VoCs! For cheap Activated Carbon Filters, look into the kind used for Aquarium filters. They'll work…
If you want this to actually work, you take a box fan, and 2 filters. You make a triangle and then some cardboard on the top and bottom to fill the gap. This increases surface area and reduces the stress on the fan due to pressure drop. Slapping a filter directly on to the box fan is going to kill the fan very quickly. https://i.imgur.com/SX1RloH.jpg
