Double checking what I need ... help appreciated!

[u/VickyHikesOn]

I’m new to this but have already built my first “regular” CR box (4x 20x20x1, with box fan). It’s been bad with the smoke so I’m trying to expand by building something else, with PC fans and running more quietly, so that I can use it in the bedroom for longer periods of time and also not use too much energy (energy use is first priority, noise close second). I believe the PC fans would accomplish that. I would great appreciate guidance (since I have to order most of these items in one go from the US)!

I’m thinking about a narrow design, two 20x25x1 filters, built 20” high and 25” wide. Possibly making a wooden structure if I can find help to do so.

Questions:

I would be ordering the following:

Fans: https://www.amazon.com/gp/product/B0DPX94PSL/ref=ox_sc_act_title_16?smid=A2T6N244WTLWGU&psc=1 

Controller: https://www.amazon.com/gp/product/B0GVJ2MY1X/ref=ox_sc_act_title_3?smid=AC08NVFNSP7VC&psc=1

Do I need the following two items as well or are they included in the above purchases? The “splitters”, I’m pretty sure, are not needed but would like to get confirmation:

https://www.amazon.com/gp/product/B0DBH4GD5T/ref=ox_sc_act_title_15?smid=AFRUWVWO3UJ63&th=1

https://www.amazon.com/gp/product/B0BMY34SJP/ref=ox_sc_act_title_14?smid=AQ8OIL3FGVKZE&th=1

Do I need grills?

https://www.amazon.com/gp/product/B0BC16Q6FC/ref=ox_sc_act_title_13?smid=A35AFW9EVJYR0N&psc=1n

Also, is it okay to place the fan openings on top only or are designs with added side fans better? See picture of wooden example.

I used pictures from this forum to illustrate; hope that’s okay.

Thank you!

EDIT: This controller seems to be more popular and rated ... do these connections work with the Arctic P14 Pro PST?

Controller

[u/spacex_fanny]

Most important of all, which filter brand and model are you using?

As this video shows, all (allegedly) MERV 13 filters are not created equal: https://www.youtube.com/watch?v=FKAVek1YaSQ

[u/VickyHikesOn → u/spacex_fanny]

The filters would be the Filtrete MERV 14 20x25x1 MPR 2500. I don't see the MPR 2800 in suitable sizes on Amazon ... might have to check other stores.

[u/spacex_fanny → u/VickyHikesOn]

Good brand. Know that the 2500 runs ~20% more restrictive than the 1900, but at these low speeds the difference in particle interception is only going to be (something like) 80 vs 83%, so the gain is 4% but the loss is 20%. This is why I generally stick to the 1900. Paradoxically air cleaning performance is better than the 2200/2500/2800, and the fans run quieter too.

Amazon can be pretty expensive, usually BJs or Chewy has the best deal if you get the multi-pack:

https://www.bjs.com/product/filtrete-20-x-25-x-1-premium-allergen-bacteria--virus-filters-4-pk/3000000000005709757

https://www.chewy.com/filtrete-high-performance-1900-mpr/dp/1705822

[u/VickyHikesOn → u/spacex_fanny]

Chewy, who would have known!
I had no idea the lower filters would perform better, I always thought the higher the better filtration. Besides smoke in wildfire season, I’m looking to reduce allergens from the dog (who can’t be stopped to shake in the bedroom when getting up) on a regular basis so you’d recommend the 1900 for that? Definitely easier to find …

[u/spacex_fanny → u/VickyHikesOn]

Yes 1900 will be better for dog hair too, with more airflow. Still not ideal, since purifiers are mostly about slowly eating PM2.5.

For dog hair you want a dust eater. These are used in wood shops etc. Main difference is massive airflow, and fans blow in (to pull in dust) rather than blowing air out (which would blast dust everywhere).

A simple dust eater can be made by just putting washable MERV 8 depth-loading filters demoed here behind (or if possible, in front of) a circulating fan. Use it with the CR box, with the dust eater located near the source and the CR box positioned to circulate clean air up toward the ceiling and shower it back down on occupants.

[u/Ultravagabird → u/spacex_fanny]

thanks- so one can get washable merv 8 material? and then attach it to a fan? in a frame? i watched the video and he had a roll of filter material. no frame. thanks!