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Experiments on a $50 DIY air purifier that takes 30s to assemble

dyno-might.github.io

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Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#121

Post by jeremywho »

JJMalina wrote: post #111
ahaucnx wrote: post #21

We have open source, open hardware build instructions for a very reliable Air quality sensor that can be used to measure PM2.5 and also CO2. https://www.airgradient.com/diy/ We have tested it extensively and it is very accurate for the fraction of the costs of commercial sensors. You can build it for less than USD 20 and send the data to our cloud server or any other backend. We also measure CO2 because if you have p…

The Plantower PMS5003 PM Sensor is unavailable to ship to the US on aliexpress https://www.aliexpress.com/item/32944660534.html Do you know of another supplier that ships to/within the US?

I'm looking for this as well.

The only think I found was https://www.adafruit.com/product/3686, but thats 4x the price of aliexpress.

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#122

Post by brudgers »

input_sh wrote: post #80
platz wrote: post #65

Earlier quoted context omitted.

Usually this means the company does not sell to consumers and is b2b only, similar to how you just can't buy something anonymously online from a wholesale distributor.

Usually, but you have three buttons on the first screen of their homepage: for schools, for offices, for homes . I don't think they're only b2b.

Volume sales “for homes”means apartments (or condos). “For Homeowners” is a different market. Usually there will be a different website for that market. It will need to mitigate “the customer is always right” attitude prevalent among consumers.

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#123

Post by phaedrus441 »

JJMalina wrote: post #111
ahaucnx wrote: post #21

We have open source, open hardware build instructions for a very reliable Air quality sensor that can be used to measure PM2.5 and also CO2. https://www.airgradient.com/diy/ We have tested it extensively and it is very accurate for the fraction of the costs of commercial sensors. You can build it for less than USD 20 and send the data to our cloud server or any other backend. We also measure CO2 because if you have p…

The Plantower PMS5003 PM Sensor is unavailable to ship to the US on aliexpress https://www.aliexpress.com/item/32944660534.html Do you know of another supplier that ships to/within the US?

Did you search for "PMS5003" on aliexpress? I found a few suppliers, and ordered one for $15.81 with shipping (4.9/5 rating; 156 orders)

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#124

Post by nkurz »

ionwake wrote: post #106

I don't mean to go against the spirit of the thread but does anyone know how these DIY compare to actual commercial products - and can anyone recommend a good air purifier? Thank you ( I will remove this comment if it is offtopic )

I think a reasonable summary is that the homemade versions are cheaper and actually more effective than most commercial versions, with the downside that they are usually larger and often noisier. The largest factor for effective air purification is airflow, and the homemade versions offer higher airflow but at the cost of greater noise and looking janky. There are somewhat reasonable fears that the homemade versions might be fire hazards, but in practice they are probably no more dangerous than the bare fans on which they are based. Really, both solutions work just fine. If looking commercial, be sure to consider the cost and availability of replacement filters. If considering DIY, realize that you don't need to get it perfect, almost anything is better than nothing.

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#126

Post by JJMalina »

phaedrus441 wrote: post #123
JJMalina wrote: post #111

Earlier quoted context omitted.

The Plantower PMS5003 PM Sensor is unavailable to ship to the US on aliexpress https://www.aliexpress.com/item/32944660534.html Do you know of another supplier that ships to/within the US?

Did you search for "PMS5003" on aliexpress? I found a few suppliers, and ordered one for $15.81 with shipping (4.9/5 rating; 156 orders)

Good call, thank you!

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#127

Post by riverdroid »

Rebelgecko wrote: post #14

I wish there were multiple reps of each experiment, especially with how noisy the results were and the difficulties of reproducing smoke Regardless, this project actually makes me feel better about buying my fancy air filter Instead of buying 2 filters (both HEPA), a fan, and a poorly calibrated air quality sensor for $150 like the author, I bought an air purifier that contains 2 filters (1 HEPA, 1 activated charcoal…

Be aware that the air quality sensor on most units is a cheap VOC sensor. It detects gasses, not particles. It'll trigger if you fart near it or cook something odorous, but not for dust or smoke.

I have the Winix 5300 and 5500 purifiers (which I highly recommend), and typically run on mode 3 out of 4 because it pulls about 12 watts (and is quiet) but is not massively different airflow than mode 4 which draws about 70 watts (and is noisy).

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#128

Post by bluGill »

post_break wrote: post #91
rootusrootus wrote: post #89

Earlier quoted context omitted.

> we'll use two 20x25x1 filters which increases the filter surface area over 250%. That seems like an overly complicated first attempt, why not just switch to a 20x20x4?

Those can be harder to source I've found. Cheaper to use two filters than one as well since you can replaced the prefilter more often.

I used a 25x20x4 which was easy to find. Even though I didn't do anything to stop air from flowing around the backside of the filter to the fan it still gets noticeably black fast.

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#129

Post by bluGill »

roflchoppa3 wrote: post #86

These boxfan + hepa filters seem pretty affordable, but seem to have a really strange physical footprint. Do SUV cabin fans not push enough CFM to be effective? https://www.rockauto.com/en/moreinfo.php?pk=10863244&cc=1502... This paired with a filter seems like it would do the job, and based on the enclosure you might be able to have a smaller footprint. No CFM data though.

They should, and probably stay closer to the rated cfm with a filter there. However now you need a 12 volt power supply instead of plugging into a normal outlet. Plus you need to design a housing for it.

Neither of these are hard problems for DIY, but they are not nearly as easy or quick as a cheap fan and some tape.

Re: Experiments on a $50 DIY air purifier that takes 30s to assemble

#130

Post by bluGill »

boredpudding wrote: post #82
abyssin wrote: post #81

I tried building a similar air purifier in Belgium last year and I've never been able to source the parts at a similar cost.

Same problem for The Netherlands here. I just want to put a hepa filter on a fan, but unfortunately I can only find hepa filters for vacuum cleaners or existing air purifiers. If anybody has a link for where to buy a regular square/rectangle hepa filter, that would be great.

This is a hepa replacement for one of the air purifiers you can buy. Just go to the store, find an air purifier, read the back of the box to see what filter it takes, then look up/down/over a shelf - they replacement filters are generally carried in the same aisle. You will probably be surprised at just how small the filters for most of those commercial air purifiers are.
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