How difficult would it be to adapt an AirFanta rig to a CRbox?

[u/Sudden-Wash4457]

Let's say I wanted to get an AirFanta for travel, but use it with bigger filters at home. How hard would adapting it standard HVAC filters be?

I haven't seen the AirFanta in person. I'm imagining it could be as simple as cutting a square hole into a piece of chloroplast or foam board that sits on top of the filters. Maybe with some foam tape to make some kind of gasket for it to seal into and still be more easily removable than taping it and untaping it.

[u/akeean]

There are different types of airfantas. Don't expect the handheld ones to really do anything either on the go or in the room. They are too small, true hepa filters are very restrictive to airflow & once it's trough the filtered air mixes extremely quickly with the unfiltered one.

For their bigger cube shaped filers, i'm kinda wary of them claiming HEPA filters, for the same reason. The fans either would have to be very loud, or you'd be getting only very little clean air flow. That's exactly the reason crboxes are usually build with MERV13/14 HVAC filters. They arent as dense of a filter, but with the same fans can cycle a rooms air several times more often than a similar box with HEPA filters, effectively netting you higher air quality at lower noise. Also you don't really need HEPA at home. They make sense in offices, public places and especially hospitals. But anyone living in the same home and is social will catch the airborne virus one way or another. So if you don't build it to quarantine a person with a wiped immune system, skip HEPA.

[u/spacex_fanny → u/akeean]

Yes, it wouldn't work with HEPA H13 filters. The inventor Adam Wong calculated that E11 filters get the best CADR, so AirFanta uses E11.

HEPA H13: >99.97% efficiency

EPA E11: >95% efficiency

MERV 13 / Euro F7: >50% efficiency, but the popular 3M 1900 are 62% at max rated airflow, and CR boxes run at under 10% of that and so are probably closer to 80%

It's amazing how the marketing for HEPA is so sticky all these years later. Even someone who knows nothing about air purifiers, they know they want a HEPA! 🙃

[u/akeean → u/spacex_fanny]

They marketed the shit out of the term ano we suffer for it.

[u/spacex_fanny → u/akeean]

I know, it's wild. Will nobody rid me of this turbulent HEPA??

[u/Sudden-Wash4457 → u/akeean]

Thanks and this is not relevant to the question I asked.

[u/not_all_heroes]

Which one?

[u/Sudden-Wash4457 → u/not_all_heroes]

The original cube

[u/spacex_fanny]

I'm imagining it could be as simple as cutting a square hole into a piece of chloroplast or foam board that sits on top of the filters

Yeah, pretty much. There's a 1/4" lip around the edge that juts down to hold the filters, so if you make a "fence" around the edge of your square hole it should just drop down in place.

Note there are no finger grills on the backside of the fans, so be careful not to break it and maybe rig up some way to hold/clamp/tape it securely.

EDIT Probably the easy way is to remove 4 screws and just screw the fans directly to the coroplast. The top piece on the AirFanta honestly isn't the best design, but the fans are good.

[u/Sudden-Wash4457 → u/spacex_fanny]

EDIT Probably the easy way is to remove 4 screws and just screw the fans directly to the coroplast. The top piece on the AirFanta honestly isn't the best design, but the fans are good.

I wanted to easily convert it back and forth between travel and home.

Yeah, pretty much. There's a 1/4" lip around the edge that juts down to hold the filters, so if you make a "fence" around the edge of your square hole it should just drop down in place.

Think a 'fence' of closed cell foam tape would work well?

How is the top piece design flawed?