11-26-2015, 11:25 AM
I am looking at upgrading to a nice cyclone.
Looking around, it looks like there is pretty much only one magazine to have tested these things, which is the WOOD magazine test.
Everyone and their brother who likes clearvue complains that the magazine must have done something wrong because they say "the CV1800LH returned more than twenty times as much fine dust to the shop as the Oneida Cyclone that topped the previous testing", and clearly, that can't be right, so they must have done something wrong in assembly, etc.
So, looking at the two cyclones in question, the CV1800LH uses a MERV15 9B300NANO filter from wynn (it really uses two of them, but it's not the case that you necessarily get better filtration by stacking filters. You get lower static pressure).
The MERV15 value means it's 84%-90% efficient at 0.3micron-1.0 micron particles.
The Oneida V-3000 uses a MERV16+ GE filter with "99.97% of particles captured down to 0.3 micron in size" (which is the HEPA standard).
The MERV and HEPA values are reported at initial loading (which is why the wynn and CV web page says the filter is 99.99% efficient at 0.5 micron particles. One value is at initial loading, one value is with 1.5 lbs of dust in the filter. See the 4th image, which is a table for the nano media, on http://wynnenv.com/filter-efficiency/
I can't direct link it because their CDN expires the image.
The numbers across the top are static pressure. Note, however, that the 0.5 micron size is going to reach 99.9% well before the 0.3 micron size does).
More to the point, let's be generous and call the wynn filter merv16, and say it's 95% efficient at 0.3 micron particles, because even though it really only starts out at 79% efficient at that size, it *very quickly* gets to 94.3% efficiency according to the table (meanwhile, our GE filter media over there is already at higher efficiency).
Great, so let's do some math.
We allow 100 million 0.3 micron size particles into the collector, and through the filter.
How many come back out of the thing?
Our wynn filter:
>>> 100000000-(100000000*0.95)
5000000.0
Our GE filter:
>>> 100000000-(100000000*0.9997)
30000.0
Whoops, so yeah, it looks like we got 5 million particles of dust back out of the wynn filter, 30000 back out of the GE filter. This is after first loading (the numbers are *much* worse for initial loading, but they always are).
This is 166 times as much dust back out of the clearvue
Even if we go with 0.5 micron sized particles, we get 100 times as much dust back out of the clearvue (96.8% vs 99.97%)
Eventually, yeah, it looks like the Wynn filter gets to 99.9%+, and then they both compare well from that point forward.
But i'm kind of stumped why people think the wood results make no sense. It looks like pretty simple application of "the oneida GE filtration media happen to start with higher efficiency", and it is going to take a while to get the Wynn filters to the same efficiency[1]
What am i missing?
[1] Not a knock on wynn of course, they will happily sell you HEPA filters or *whatever*. it's just what happens to be on the clearvue. In fact, I love Wynn, i've bought a bunch of their cartridge filters over the years.
Looking around, it looks like there is pretty much only one magazine to have tested these things, which is the WOOD magazine test.
Everyone and their brother who likes clearvue complains that the magazine must have done something wrong because they say "the CV1800LH returned more than twenty times as much fine dust to the shop as the Oneida Cyclone that topped the previous testing", and clearly, that can't be right, so they must have done something wrong in assembly, etc.
So, looking at the two cyclones in question, the CV1800LH uses a MERV15 9B300NANO filter from wynn (it really uses two of them, but it's not the case that you necessarily get better filtration by stacking filters. You get lower static pressure).
The MERV15 value means it's 84%-90% efficient at 0.3micron-1.0 micron particles.
The Oneida V-3000 uses a MERV16+ GE filter with "99.97% of particles captured down to 0.3 micron in size" (which is the HEPA standard).
The MERV and HEPA values are reported at initial loading (which is why the wynn and CV web page says the filter is 99.99% efficient at 0.5 micron particles. One value is at initial loading, one value is with 1.5 lbs of dust in the filter. See the 4th image, which is a table for the nano media, on http://wynnenv.com/filter-efficiency/
I can't direct link it because their CDN expires the image.
The numbers across the top are static pressure. Note, however, that the 0.5 micron size is going to reach 99.9% well before the 0.3 micron size does).
More to the point, let's be generous and call the wynn filter merv16, and say it's 95% efficient at 0.3 micron particles, because even though it really only starts out at 79% efficient at that size, it *very quickly* gets to 94.3% efficiency according to the table (meanwhile, our GE filter media over there is already at higher efficiency).
Great, so let's do some math.
We allow 100 million 0.3 micron size particles into the collector, and through the filter.
How many come back out of the thing?
Our wynn filter:
>>> 100000000-(100000000*0.95)
5000000.0
Our GE filter:
>>> 100000000-(100000000*0.9997)
30000.0
Whoops, so yeah, it looks like we got 5 million particles of dust back out of the wynn filter, 30000 back out of the GE filter. This is after first loading (the numbers are *much* worse for initial loading, but they always are).
This is 166 times as much dust back out of the clearvue
Even if we go with 0.5 micron sized particles, we get 100 times as much dust back out of the clearvue (96.8% vs 99.97%)
Eventually, yeah, it looks like the Wynn filter gets to 99.9%+, and then they both compare well from that point forward.
But i'm kind of stumped why people think the wood results make no sense. It looks like pretty simple application of "the oneida GE filtration media happen to start with higher efficiency", and it is going to take a while to get the Wynn filters to the same efficiency[1]
What am i missing?
[1] Not a knock on wynn of course, they will happily sell you HEPA filters or *whatever*. it's just what happens to be on the clearvue. In fact, I love Wynn, i've bought a bunch of their cartridge filters over the years.
