Air Cleaners - 1 big, 2 little ?

[Mark Visconti]

What's the conventional wisdom on number of air cleaners? A Jet AFS-1000 is in the $200 price range (1044 advertised CFM max). A AFS-2000 is in the $550 price range for 1700 CFM.

Any reason to go with a single AFS-2000 vs multiple AFS-1000s? Assume primary DC is a cyclone. Shop size is 35x16x8 but there is an adjacent area (35x12x8) to the shop that I'd rather not be a dust pit.

It seems I could go crazy and get 3 AFS-1000Bs at close to the same price and put 2 in the shop and 1 in the adjacent area for extra cleanliness overkill. It seems that I would move a lot more air and have a better distribution.

Thanks,
Mark

[Brad Townsend]

Sounds reasonable from a cost standpoint. However, I'm not sure that you would really need TWO AFS1000Bs in the main shop area. Just basing this on my own shop. I have only one in a 30x20x9 shop and it seems to do quite well. I'm sure two of them would be better, but before I would spend the extra $200 on another filter, I would upgrade my DC for better suction at the tools themselves. But that's my situation and perhaps yours is quite different.

[Mark Visconti]

That's another advantage. Buy one AFS-1000B now, if it doesn't suck enough, buy another.

[Wilbur Pan]

All other things being equal, having two smaller air cleaners will be better than one big one. The reason for this is that one of the limiting factors for how well your air cleaner will clear the dust will be how efficiently the air recirculates in the room. With one air cleaner, it will take longer for the dust particles far away form the air cleaner to get trapped because they have longer to travel to get there. With multiple air cleaners, you will have better coverage and more efficient clearing of dust.

I've come to believe that the usual CFM recommendation for air cleaners for a given shop size is much lower than what is ideal for rapid clearance of dust. My feeling, based on some calculations I've been playing around with, is that you need a total CFM of about 50% of your room volume for optimal performance. Without going through all the math, it looks like at this level of coverage, 99.99% of the airborne dust will be cleared in about 30 minutes. Luckily, your two AFS-1000 units should provide that for your shop.

I would get two AFS-1000's, put one at each end of your shop, and see if you need additional coverage for your adjacent area. My shop is half your size, and I've got one air cleaner.

[glenn bradley]

The usual hated answer; it depends. What is dividing your two areas? A small door? A 25 foot wide arch? You get the idea. If the air spaces are reasonably divided, two cleaners is probably the answer.

As another poster stated; get one, if its not enough, get another. Win, win situation. I have a 21 x 31 x 8 shop (single room) and I run an 1150-ish CFM scrubber. Works well for me (unless I'm free-hand routing MDF with my "no DC" router, then nothing helps).

[J.R. Rutter]

I agree with Wilbur, and would add that the ideal situation is to set up an air flow pattern that puts clean air where you are standing and moves dirty air quickly to the filter intake. A pair of filters can set up a circular flow to do this.

I prefer having filter units near the floor. I recently moved one up high, and find that it doesn't get dirty anywhere near as fast as it did down near where I made my dust...