AC Infinity 4-Inch Inline Filter Box with High Efficacy Filter

After installing an ERV, I noticed the intake air is not sufficiently filtered and that caused PM 2.5 particle counts to go up in the house. This filter is a great solution and I placed it before the ERV to filter the intake air before it reaches the ERV. This has dramatically reduced PM 2.5 particle count back to normal range.It's easy to install and is very solid. It doesn't come with any means to mount the filter or hang it. It's also not insulated so it can condensate if outside air is much colder than inside. I was worried about the box but it was well packaged. Finding the right filter for the 4 in and 6 in version might be a problem, but I think the Home Depot HDX 12X20 MERV 13 filter should fit based on the size of the filter online. But I am using the provided filter at the moment.

We used this 6" model for a fresh make up air for our house. Reading the review we realized people were upset that AC Infinity doesn't sell replacement air filters and those readily available filters at the big box store won't fit.If you are searching for a replacement then buy the Nordic Pure 12x20x1. Amazon sells this brand of filter as well. The actual measurements for this filter is:11.5 x 19.5 x 0.75 inches.Although this air filter is about 0.25-.05 in short on the length and width, it still fit the air box and the seal is still in tact.See pictures for a visual illustration and reference my finger.As for the air box itself, this is a well constructed and high quality air inbox. This is expensive but I believe the quality and craftsmanship justified the price.I hope this review helps.

This box looks so good, it's almost a shame I have to mount it in a hidden area.It's solid. It's tough, and the finish is great.The box it was packaged in got heavily damaged in shipping, and the strength of the air handler itself is what saved it from damage. Only a few nicks to the powdercoat finish, no discernible dents, and no affect to the body or door.It latches solidly, seals competently, and comes with a pleated filter already included inside it (independently shrink-wrapped, of course)I also bought a pair of backdraft butterfly dampers (6" as well) from AC Infinity, and their build quality blew me away just as much.I'm really impressed with this company. Yeah, their stuff isn't the cheapest, but you really get what you pay for with these people. I'll be trying to use their products in future projects as often as possible.Highly recommended!!

I live in an area plagued by wildfire smoke and every year gets worse. I live in a Valley so temperature inversions are common and many of my neighbors have wood buring stove and some even illegally burn thei household garbage.I have indoor air cleaners which keep my indoor air quality index (AQI) very low, 1 to 4. However, Carbon Dioxide (CO2) levels get very high, especially in the bedroom when it can reach as high a 1400 ppm in the morning. Anything above 1000 ppm can cause headaches, fatigue, and other health issues.I assembled the system pictured it consists of the following:* AC Infinity Inline Filter Box fitted with Filterbuy 12x20x1 MERV 13 rated filters* AC Infinity Cloudline Pro S4 Inline Duct Fan* AC Infinity Flexible 4-inch Aluminum 4 layer HD Flex Hose (25')* Broan-NuTine 465B 4" to 5" Duct Adaptor* Gulrear Portable AC Window Vent Kit 5"I assembled these components and it allows me to draw in air from the outside, filter it, and disperse into the room. The 25' hose allowed me to place the outlet just below the top of the ceiling where monitoring have indicated is the best location.I use the IQ Air Airvisual Pro N1 indoor air quality monitor in the bedroom to track the AQI Index and most importantly for this purpose, the CO2 level. Prior to installing this system my highest reading in the morning averaged 950 ppm. Now I average 650 ppm. My 24 hour/day monthly average went from 735 ppm to 588 ppm.I am very pleased with the performance of the system and achieved my goal of reducing CO2 levels when I am unable to open the windows due to unhealty outdoor air quality.The AC Infinity products are of excellent quality and the inline Duct Fan is very quiet. I leave set at the 5 (out of 10) power level and it is very quiet. The combination of my air cleaner and the AC Infinity fan makes a great white noise level for restful sleep.In the pictures you will see how I have hidden some of the components under a chair. You can also see the hose outlet hidden behind the flower vase on top of the armoire.Update: Condensation inside the filter box was a concern, but with outside temps since installing in mid-October ranging from 65° to 22° F we have had zero moisture build up inside the filter box. Dry as a bone.