NORTHWEST ENTERPRISES Vent Filters Media Roll, 25ft x 12in x 1/8in Cut to Fit Vent Filters for Home and Business. Electrostatic Air Filter Media Roll for HVAC, AC & Heating, RV's, Mobile Homes & More.

Great solution to dust issue in my shop.

I bought this to create an in-window evaporative cooler, so we don't have to run our A/C unit, which takes ~6 kW, whereas our two box fans take about 80 watts total on medium speed.I went to Home Depot and got some LeGrand CordMate cord channels, and some small metal rods 4' long (slightly smaller in diameter than an extension cord's diameter). I cut the filter media into 38" long sections, then lined up the top of the filter media with the cord channel, then pressed the metal rod into the slot of the cord channel, trapping the filter media in the cord channel. I overlapped the sections of filter media by about 3" to get 38" width. The window screen is 36"x36", so the filter media covers the entire window screen. I used scissors and an X-ACTO knife to cut the cord channel and filter media to 38" width.Then I screwed in two small open eyebolts outside the window, and hung the metal rod on the eyebolts.Then I pounded in some 5' stakes and zip-tied misters to them, two for each stake, one near the top of the filter media, one near the center. I used 3 stakes, so 6 misters total per window. Two windows, so 12 misters total.You can order the misters on Amazon, but the brass mister heads that come with the misting systems are junk... they don't spray well and they clog quickly with mineral deposits. I got some stainless steel mister heads that screw in to replace the brass mister heads. They work well with standard water pressure, the mist is really tiny droplets (so small that none of it hits the ground except at night when relative humidity is high, and in fact, on a hot day you can see the mist coming off the mister head and convecting upward (humid air is more buoyant than dry air)), they haven't clogged yet, they only put out ~0.25 GPH each, and cleaning them is as simple as unscrewing them, dumping them into a bowl of vinegar for an hour, then rinsing them off. Maybe brushing them with an old toothbrush if they're really coated with mineral deposits, but that's it. I haven't had to do that, as the water goes through a 400 GPD reverse osmosis unit to remove most of the mineral content. The RO waste water goes to water the yard (which we have to do anyway, so we're essentially getting the cooling for next to nothing).I positioned the stakes so one was on each side of the window, and one right in the center.I positioned the misters such that the ones on each side of the filter media sprayed parallel to it, across the filter media, to create a fog outside the window that the fan sucks in. The ones on the stake in the center of the filter media I aimed directly at the filter media.So it's 102 F outside right now, and inside is comfortable. We've hit 110 F before and we still haven't run our A/C unit yet (except for once to test it after I cleaned it and straightened the fins).I was informed that this sort of system wouldn't work in Texas because it's "high humidity'... except relative humidity (RH) decreases as temperature increases, so as the temperature climbs, the evaporative cooler works better to cool the air. In the morning, our RH is ~75-85%, but as temperature climbs, it drops to ~20-40%.So the two box fans, running on medium speed, take only 420 watts more power running all day, as the A/C unit would take running at 25% duty cycle for an hour. This month, we've only used ~12 kW per day for the entire house. It would be approximately triple that just for running the A/C 24/7 at 25% average duty cycle.And the total amount of water we're using is ~72 GPD. Water is cheap, electricity is expensive.

We have only used for a week. Finger prints on slats show that it is catching dust. Air is still flowing through fabric. We feel better. Also our home is not as dusty. Will know more in a week.

At first I thought this was not going to work, product is very thin but I didn't want to return it so I place it on all my vents. Easy to cut and to install the roll is big you will not run out any time soon. I did notice that that dust has minimized around the house, also the large HVAC vent filter does not need to be change as much. Hope this helps and yes I would purchase it again.

Excellent optional filtration for our mini-split A/C system that's in a dusty area without jepordizing the system performance.

When I was shopping for a prefilter, it was for the purpose of extending the life of a far more expensive HEPA filter. I hoped to keep out of the HEPA filter both micron size dust particles and cat hairs. I had mistakenly thought there would be a filter media that could facilitate both functions via a truly electrostatic feature. I now conclude that no such animal currently exists in the market ; at least not as a cut-to-size item.This item is a superb value as a cut-to-size, disposable prefilter dedicated for pet hair capture only. Its a very "open" prefilter media, such that you can see objects placed behind ( see attached photo image ). It's not designed to be a dust filter. It cannot begin to capture the largest dust ( e.g. dander ) particles until it becomes so loaded with stringy contaminants ( first pet hair, later textile lint ) that its openings become small enough for that to happen. However, long before that occurs, its resulting ( increased ) resistance reduces the airflow to an unsatisfactory level, requiring its replacement.At the time when I placed an order, its specs lacked a MERV rating, but because "electrostatic” was claimed the implication was that it’s suitable for some degree of dust collection. Well, nothing could be farther than the truth. Even if its openings were small enough to trap dust, when new it fails to hold a sufficient electrostatic charge for more than several hours, even while handling already clean air. A true electrostatic filter has multiple layers, usually composed of polypropylene, not polyester, and doesn't lose its charge merely due to air friction. A true electrostatic air filter can stay in service ( handling dusty air ) for at least weeks before its electrostatic property has significantly diminished.I tested this item's electrostatic property as follows :– Handled it via nitrile rubber gloves– Charged it up via a soft, broad bristle brush with a plastic handle– Used cat hairs extracted from my vacuum cleaner as test specimens– Installed this item as a cut-to-size prefilter to fit a Acecool AF1 air purifierFrankly though, an electrostatic property is absolutely unnecessary for a prefilter such as this one. As-is, this item works optimally as a very inexpensive prefilter for preventing pet hair from loading a far more expensive dust filter. So, considering its currently rock-bottom price, I would've given it a 5-star rating had its Amazon page not falsely described it as “electrostatic”. That claim draws the attention of prospective buyers who are shopping for a cheap DUST prefilter, which it absolutely is NOT.

Though pricey its worth the cost. Have been installed for a week and we already see a huge improvement with indoor air quality. Looking for others ways to improve our system using Northwest

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