Air filter for your camper

So we run the fan on our camper all the time. The prefilter is ok but it seems to trap quite a bit of dust in just a week. I was thinking that we should consider a air purifier, plus to cut down on any formaldehyde.

Has anyone figured out a way to either adapt or what air filter they are using?

I noticed the same thing, I was wondering about this site:

So a website, forgot which one did a review on air filters. They ended up taping a HEPA filter to a box fan. Turns out compared to dedicated air filters in their tested it worked pretty well.

With that being said we should see what would fit over the grill opening. I wonder if we could design a clip of some kind to hold the filter up?

I have been thinking about this for a while. I was considering having custom MERV 13 filters made and testing to see if that would work. Right now I have two of these Blue Pure 411’s running, which I am very impressed with so far. These have a better HEPA filter but I got them for one because of the cost - upfront and ongoing filters. The other key is on low they only use 1.5 watts which is important when I am off grid.

Humm this Blue Pure big? How loud is it? I worry about the VOC’s in the trailer myself, it never seems I get enough fresh air especially when running the AC or heat when we don’t have the windows or vents open.

I just measured my filter and it is 14" x 7.5" - it looks like I could possibly fit a custom sized furnace filter in that space. I quickly looked and some filter delivery services make custom sizes but you have to order a number of them. I am not sure I want to spend $200 on a experiment.

The fan runs on three levels, low - medium and high. I run it on high once and a while but most of the time I run it on low and it would be a problem to to sleep through. Medium could be dicey for some people who are not accustom to noise at night. Loud is about the volume of a conversation.

The gray part is actually blue. This is the pre-filter fabric that fits over the body. We just wash this once a week and it came with a second one you can put on while that one is being washed. The key for us was the VOC’s in the trailer.

What’s wrong with the one that comes with our trailer? You can buy spares in Amazon?

It does not actually filter much, just the large dust particles. I have wondered about this in the past, especially in the summer when the AC is on and we don’t have the windows open. The suggestion from @TheSpareTir3 about the Blue Pure seems interesting but something in the vent would be better.