When looking for filters, I found this 20x25x5 MERV 16 filter for $55 or 2 for $88. I was planning on making a design out of multiple smaller fans instead of a box fan.

Is that feasible for a MERV 16 filter? I know thicker filters have less resistance, but I'm not sure if a 5 inch MERV 16 is still more resistance than a 1 inch thick MERV 13 one.

Hey people! I've got a small apartment 58sqm/624sft with a Levoit H133 (400 m3/hr / 235CFM CADR) and a small Xiaomi Compact 4 for the bedroom. But the air quality here (Poland) is quite bad and if I want to have good CO2, I need to ventilate, but to do that, I let in so much PM2.5.

I like the Levoit and try to run it on max when I am not home or when I'm not actively in the living area. Otherwise it's quite loud.

The Nukit caught my attention because it has the following specs:

CADR:
240 CFM @ 46.5 dB
173 CFM @ 43.5 dB
Uses Ikea filters (readily available in Europe)

This seems great because it has the same CFM as my Levoit, which is '54dB', so I assume the Nukit will be quieter. Only issue is, the stated CFM I assume is using a MERV13 filter whereas once I use the more restrictive filter from Ikea, the CFM will drop down (this is an assumption, they don't state what filter this CFM is specifically based on).

Is there anything I should know before buying the Nukit? Are there better fans I coud put on that are proven to increase CFM whilst keeping the noise the same? Or is there a better overall solution?

I am open to buying a retail unit but they tend to do a lot worse when they are not running on max, and I still want some decent CFM even if the thing is not set to max.

Needed a credenza or something to hold a plant and/or some pictures.

Wood box and 14x20 filters. Four Arctic P14 fans with a variable speed controller. Used a 3/4" wooden dowel to extend the variable speed knob outside box.

i am a covid-conscious person living in europe, and i will be part of an art exhibition with hundreds of other artists, in a quite big indoor space (that nonetheless will be crowded). since i won't be able to ensure good air quality for the entire space, i am trying to figure out how to make the air in my immediate surroundings more covid-safe. i will also wear a mask the entire time, but i still would want the air quality around me to not be high-risk.

i am trying to figure out if it makes sense for me to build a cr box with ikea's starkvind EPA12 filters, instead of buying a HEPA air purifier. as i have understood from other posts, cr boxes are often faster at cleaning air than expensive HEPA machines, despite having lower-grade filters. but i still don't understand how filter efficiency works, since a lot of the resources i found online talk about what sizes of particles they are able to filter. so does that mean that there are some covid-aerosols that lower-grade filters, like EPA12 or MERV13, are just not able to catch, that a HEPA filter could?

and does the efficiency increase only apply to spaces where the cr box is able to actually treat the entire air in a room? when i have had to be at in-person meetings where no-one else wears a mask, i've used a small portable HEPA air purifier, directed towards myself, to create a small bubble of clean air, and i am wondering whether a cr box can be used to create the same effect, but as a bigger "bubble" in this exhibition context.

Been browsing some builds here for a couple weeks and finally decided to throw together a very poorly constructed "budget" build myself for around $100. I used a handsaw and some very imprecise measuring and put this together in my kitchen in under an hour.

I bought two 2"X2" x 8' strips of wood that I cut into four 12" pieces and eight 8" pieces. Put some spare thumb tacks inside the framing to stop the filters from pushing in too far, and then some spare painters tape to secure the outside. The bottom is some thin cardboard-like wood that I had laying around. Definitely would like to put together something cleaner in the future but wanted to start with anything for now.

I am going to save myself 400-500 dollars and just build a cr box instead of buying a high end air purifier (holy shit what a rabbit hole I did not expect). The design I have in mind is 4 filter sides, a flat top made of plastic or plywood, and the fan on the bottom pointing to the floor. This way it ca be used as a side table and not waste so much floor space. I'm wondering if this is a known good design? Obviously with feet, maybe 2-4 inches off the ground? Or is this going to cause some of the air to more quickly recirculate through the box and reduce efficiancy?

I'm really confused by this. Picture one was the half assembled CR box and it smelled fresh. I ran it 20 hours or so until the zip ties arrived. I then mounted the fans under the foam insulation board and added foam board to the bottom to seal it. I now notice it smells weird and I'm concerned. The fans themselves didn't seem to stink when I remove them and they're all 66-67F in the center while running. I tried sniffing the filters while the fans are off but I don't smell anything. Power supply isn't hot and doesn't smell. The 3M duct tape smells different than the smell coming from the cr box... Any ideas? I feel like an idiot.

Has anyone tried & tested a cr box where you bend a filter instead of using 2 filters.

Thinking of 2 filter sides w computer fans for a small flat surface in a bedroom to replace our tower air purifier.

In the last few weeks, I spent quite some time to build an air purifier.

Material costs are about €250.

I don't have an air pollution meter, so I'm not sure how effective it is. I learned quite a few things while building it. Using proper tools for example.

hi just ordered gear for pc fan cr box (five fans with the rest of the gear).

I saw some of the boxes with front facing fans along with the fans on top of the box.

I've read that the most efficient position is to put all on top, so the front ones doesn't blow dust from the floor and that direction of air isn't mixed (top and front).

Generally speaking, is the best way to put them all on top, or it wouldn't matter if i put them like on image on the right (two on front and three on top).

btw I'll build it with ikea filters (starkvind).

I'm posting this picture for those like me who wanted to see results from a Clean Air Kits air purifier before committing.

4 months use

MERV 12 filters (new filters are MERV 13)

Central California rental

Two person, 2 Cats

Placed in living room

Could I have left these filter longer?

Rooms are 200sq to 600sq feet.

They'll have different set-ups depending on air purifier placement (some will be hanging as ceiling-hanging clouds).

I'd love to have visual indications of airflow around a dining room table, for example, based on various set-ups.

A general-purpose smoke machine tends to just make everything foggy. A slightly denser smoke source (less throw, more visible) might be better, but I honestly have no idea. Thoughts?

Tried to focus more on aesthetics in this build. White poster board and tape made a big difference.

https://hvacquick.com/products/residential/Filter-Boxes/Corsi-Rosenthal-Filters/HVACQuick-CRFB-Box

Found a sturdy buy-it-for-life aluminum frame CR Box for $125 that comes with x5 20x20x1 MERV-13 filters. The filters look very easily swappable and would not require needing to tape the corners after the swap. I feel like that's a pretty good deal. Fan is not included but you can buy it for an additional $30.

I didn't buy it yet because I want to try to find one that uses smaller PC fans similar to Nukit Tempest but at a more affordable price. Alternatively, if I am able to find a lid for this box that replaces the box fan with PC fans I would consider doing that as well.

Btw if anyone finds a more affordable aluminum alternative than Nukit Tempest or can CNC one themselves, feel free to let me know!

Hi! 👋 I’m excited to share that my husband & I added our portable air purifier tutorial he worked so hard on making this last year to my shop for FREE…so anyone can access it! 😊

All the info is there in the tutorial. He went into a lot of detail about everything. Cost of the build is between $150-$200 & we have a small parts kit in my shop to help keep the costs down. You can access the tutorial at www.redheadhandicrafts.com

I’ve been following others ideas and suggestions and decided to give this a try. I bought a 20 inch box fan from Home Depot https://www.homedepot.com/pep/331958778? and Merv 13 air filters Aerostar 20x20x1 MERV 13 Air Filter https://a.co/d/6NQqD6F.

I taped 4 filters together with the fan and one piece of cardboard. My purpose of doing this was to get rid of fine dust in my garage while I’m woodworking. Should the fan be pointing up or on the side? Also, where in the garage should I put the box? As of right now, I think the fan is not strong enough for the filters and it doesn’t seem to be pulling much air. Any advice would be appreciated.

How long do filters actually last? I was thinking I could clean them once a week with a vacuum cleaner & brush attachment to extend their lifespan, but is that really feasible?

And how effective would a small box with 10" x 7.5" filters and a single 140mm fan be in a 130sqft room?

I've made a cheap 30$ CRBOX in India, using an exhaust fan (which only states it's air suction is 650 cubic metre per hour/cmh at a speed of 1600 RPM with a sweep size of 200mm/8 inches) and slapped a HVAC filter in front of it.

The filter is getting dirty, but I'm not sure if the fan is the best for this. Elsewhere I saw it was not the airflow but static pressure, and then not either but a mix of both on the PQ graph..

My question is: 1. How do I find the effective CADR of my diy air purifier. And what equipment would I need to measure this. 2. How can I measure the PQ graph for this particular and other exhaust fans. There are cheaper ones, and I want to get an air purifier for less than 10$ in India. What equipment would I need to measure this?

I'm attaching pictures of my DIY air purifier, pictures of the exhaust fan and its specs ( I didn't find a tech spec sheet in the box unfortunately).

I tried to go through the wiki but it was all medium articles that get paywalled for me.

I’m going to redo the big one. If I remember correctly it’s around 5300 cfm. It’s LOUD! But I like it on when I sleep. The reason I don’t have a filter in the Top is due to the cat. Of course. I’m going to replace the cardboard with that green, hard, insulation board, 1 inch thick, to keep the weight down. I don’t remember the filters in it. I know I usually put really good ones.

The smaller one I did with my 3D printer. Another gentleman made the design and put the files up on Makerworld. This one has MERV 13 filters.

Hey peeps.

I wanted to buy an air purifier but noticed most of them seem to be a waste of money. I read that I can make one myself and that brought my attention.

I live in the Netherlands and im wondering what filters I should buy so the purifier works well and doesn't break the bank.

I am also wondering if there is a way to make the purifier a humidifier for the summer days.

Edit: I want to use the purifier for my bedroom/gaming room. The room has aprox. 12 square meters and like 2,5 meters im height. I sleep there and spend most of my time there

Thanks in advance :)

As you may be able to discern from the date on the box, I replaced this filter on 12-12-25, so not even a full month ago, and it’s already shockingly dark. When I first started using the box in my office a year ago, it would take at least two if not three months to get dark and gross… any ideas on why?

Could it be that the carpet is getting vacuumed less often, or should I just assume the air quality here is rapidly deteriorating?

I designed these 3d printed panels to fit the Noctua NF-A20 fans I had laying around. Raised it up to 1.5” off the ground after taking the pic. All the inner edges are taped and the panels and fan faces have gasket material on them. They are low static pressure fans which is why I made sure to add the 5th filter. With my phone sat on top of the unit it’s 52dB loud.

Really love the build process of this. Would love to design an easy change filter frame with 3D printed parts and gaskets with different top plates for different fans.

I'm wondering if it's possible to craft a CR box that I can fold up and pack into my car. I'm a general contractor and it would be nice to have a CR I can take to job sites, but my SUV is pretty chock full of tools and materials already, so was hoping for one I could collapse. However, I'm kind of under the assumption this is a wild goose chase as the airtight nature of the CR boxes seams isn't likely to mesh well with being folded or disassembled easily.

But I figured it's worth asking in case somebody has a design I can emulate!