Same results on auto air filters, K&N vs other cheaper ones. Lets in more air, but also lets in way more particles.
This guy has a TON of interesting such videos.
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That is an unsolvable problem. It all comes down to pore-size, small pores catch more but restrict flow more, and once a pore has caught something it is closed off.
In critical filter processes the difference between pressure before and after is monitored and must be high or you know the filter is not filtering.
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That’s interesting. The HVAC people I’ve had out all advise to use the absolute cheapest filter I can find, like the thin, old-school fiberglass-weave ones. These guys swear the 3M filters (and all the other pleated filters) “make the blower work harder”. This despite the unit itself has a big sticker on it from the factory advising the use of a name-brand pleated filter. I use a 3M filter.
It’s crap like that that makes it hard for me to trust the opinions and recommendations of anyone in the HVAC trade.
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When I bought a new HVAC last year I had to sort through many differing professional opinions. I found a good board of pros and many differences of opinion about brands they like, though they all agree that quality of installation is more important than hardware.
Yes, a higher MERV rating will make the system work hard because it blocks more air, that is why you don’t buy a higher MERV rating than you need. But you need the filter to block tiny particles, so easier air flow doesn’t help if you are letting dirt in. The desired MERV rating depends on a variety of factors such as commercial vs residential, pets vs pet free. But dust accumulating over time with screw up the blowers. I learned this after blowing a couple a couple of blowers.
Can you please add the electrostatic filter to your chart? Unless I missed something, it seems to outperform most of the competition.
@cowwoc
Not especially. While lower is better for the measures shown, at a stated “Large Particle Count” of 3295, it doesn’t perform that much better on average than the cheap $5 filters. Barely outperforming a $5 filter just isn’t high praise. 
Its relatively good “Dirty Static Pressure” performance of 0.53 may well be for the same reason the 99-cent fiberglass EZFlow filter scores so well (at 0.26 – also not charted): it just doesn’t catch much! 
Not to say that a washable filter may not be all people with no significant air-quality or allergy issues need – with an eventual low per-use monthly cost as a bonus. But at the same time, neither of these measurements put it particularly close to contention with the performance of the most-effective (and expensive!) 3M and Honeywell solutions.
Does it really matter where the filters are manufactured?
It probably does to Americans who want to buy American. :shrug:
While I was watching the video, I vacillated between it being some jingoistic bullshit metric and being just another data-point that he could easily provide.
I will say that I found good advice from another video this guy made when I needed to rejuvenate the plastic lens on my car’s headlights.
But does that match real life? He duct taped the edges, so I think his values will be really high. Who on earth doesn’t have 1/8" of space all around the edges of where they put their furnace filter?
It also means that more particles get through (again, around the edges) than he measured, and ultimately that the quality of filter isn’t quite as important. Unless you have a perfect seal around it I guess.
You can’t see me, but my hand is raised. We have a two returns. In one, the filter fits perfectly snug. In the other, the box is actually about 1/8" smaller than the filter, so I have to crush it a little to make it fit at all.
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Yes but you didn’t say whether you live on earth.
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@shrimple You are right, of course. My point was that if you are looking to buy a “good enough” MERV-8 filter with low resistance and low lifetime cost then the electrostatic filter seems a good way to go. Anyone who goes for the 3M or Honeywell solutions by definition is not price-conscience. There is nothing wrong with that.
It sounds like if you want a “good enough” MERV-8 filter, you should go for the electrostatic model. If you want a top of the line filter, you should go for the Honeywell.
There is a happy medium, though, which some of those filters met.
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