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by odensc 1110 days ago
Isn't $100 (the stated cost to make this) the same as a proper air purifier like a Levoit Core 300?
4 comments

The Levoit, and basically all 'consumer' purifiers, are extremely under-powered and generally have very low air clearance rates & CFM. Usually relatively/overly expensive filters, too.

To get a remotely apples-to-apples comparison, look at commercial air purification systems -- think devices intended for areas that allows indoor smoking, such as bars/casinos/smoking rooms/etc.

My experience was that a relatively modest 20x20 (x12' high) room requires a massive amount of air movement, and products actually designed for spaces of that size generally run $3-6k or more.

A Corsi-Rosenthal box can delivery very good PM2.5/PM10 numbers, even with challenging environments & when "stretched" to provide purification for an entire home.

PurpleAir or a similar quality AQ monitor provides some very objective data to guide you; I trashed my Levoit purifiers rapidly after realizing just how ineffective (and expensive) they were versus a CR box.

Really not sure what you're talking about.

The Levoit moves a lot of air on its highest setting. The filter is $23 and lasts for 6-8 months. It works amazingly and effectively in a bedroom or living room or office. I know, I use them and measure my indoor air quality with an Awair.

The CR box is probably far more powerful, yes, but it's also gigantic. You'd never put it in a bedroom or living room. I'm honestly not sure where you'd put it.

Seriously. Plus the Levoit gives you adjustable fan speed to balance noise vs effectiveness, set a timer, it tells you when to replace your filter, it looks nice and professional rather than garage hardware, etc.

If it were a quarter the price then I appreciate a DIY thing, but this is already in the same ballpark price-wise as the best-selling air purifier on Amazon. I don't get it.

These sorts of fan setups also use a lot more electricity than a dedicated air filter with similar stats. Not a big deal if you're just running it for a few days, but something to keep in mind.
The Levoit filters are twice as expensive to replace.
What is that calculation based off of? The article lists the 4 filters as $70 (which I'd assume you would replace all at once).

The Levoit uses 1 filter "unit", and filters are $55 for a 2-pack on Amazon ($27.5/ea), or half that if you trust the third-party ones.

Levoit recommends to replace the filters every 6-8 months, so you could get 12-16 months of filtration for $55. I can't find any calculation in the article for how long the author estimates their filters would last.

They don't seem like it.

Levoit filters are advertised as lasting 6–8 months and cost $23 each.

Meanwhile a set of four filters like the one in the tutorial cost $70 and looking up comparables online at that price point indicates they're good for 3 months.

So even if using 4 at a time extends to 12 months, that's still more expensive than the up-to-2 Levoit filters you'd use in that time.

I see zero cost benefit here over Levoit -- it seems to be more expensive actually?

The Levoit mentioned (I have one) is tiny and only good for a small room. The comparison box fan filter can clean a lot more air over the same time period.
It's good for a large room, not just a small one. I have one too.

The CR box is tremendous overkill for something like an apartment. It's gigantic and I don't even know where most people would put one even in a house.

But it's also not what the original post was talking about. The original post is a device akin to a Levoit in terms of size and power.