AC INFINITY 8” for 6” ERV Panasonic
Shawnnixon1
| Posted in General Questions on
I want to buy an air filter box for my Panasonic IB200 ERV, Long story short filters are crazy expensive. Can I buy a 8” filter box when my ERV duct size is 6”?
Reason why is that AC infinity and Famtech 6” airbox dont use typical 12×20 filters its like 19.5 or something and they dont even sell the filters easily and if there is its expensive but saw reviews AC infinity 8” uses standard 14×20
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Will a reducer make it any less efficient? Is there cons?
If you install the reducer correctly and seal up the joints properly, there shouldn't really be any cons.
I'm in the erv planning/shopping phase and the main inline filter that has caught my eye is here https://www.hvacquick.com/products/residential/Indoor-Air-Quality/Inline-Filter-Boxes/HVACQuick-CFB-Series-MERV-13-Inline-Filter-Boxes
They have either a 4 inch thick 14 by 14 inch filter option for a 6 inch duct or a 24 by 24 inch version and their filter prices are good. Other places sell 24 by 24 inch filters as well. If anything the larger filter/duct should help.
I’m in Canada not states and not available here
That's odd, they list it as an item they ship to Canada.
They do ship to Canada.
Yes you can use an 8". I have the 6" HVAC box with the 16x16x4 filters and resistance is very low at 110 CFM. If you are pushing 200 CFM, the 8" filter box will ensure that static resistance is kept low. With MERV 13 in the filter box, PM2.5 never exceeded 60 in wildfire events, which is still a lot higher than our typical baseline of PM2.5 at 2-3 ug/m3. MERV13 works quite well in the filter box, aside from heavy smoke outside. See below for my solution to this.
I'm currently constructing an external box (will be wall mounted, outside) to use a 16x24x5 filter, and an 8" Terrabloom canister carbon filter (for wildfire smoke etc) that can be excluded/included from filtration as desired. I watched the BS and Beer on wildfire smoke and filtration and was interested that no one mentioned an external filter box as an option, much like a commercial building uses a rooftop package. All filtration is outside, addressing the limited indoor space issue with many installs. I'll post up details once complete.
In that case youre saying an 8” filter box with 6” reducer works better than a 6”? How do I make sure air is not escaped through the reducers
I would use mastic or aluminum mastic tape on all seams to minimize air leakage. I used nashua foilmastic sealant tape when ducting my range hood and something similar should be available in Canada. https://www.homedepot.com/p/Nashua-Tape-1-89-in-x-33-9-yd-Foilmastic-Sealant-Duct-Tape-1542730/302091382?MERCH
The 6” version does this mean the max airflow is 75CFM? Are these models good?
Nevermind they dont use “standard filters” the 6” use 13.75x13.75 and the oversize is 24x24x4
Keep in mind that the filter box will need to go on the fresh air supply from the outside so it needs to be insulated. I wrapped mine in foil faced rigid insulation and taped the seams except for the access panel. The access panel has a piece glued on with small holes through the rigid where the cover fasteners are so the panel can be be removed to swap the filter without taking any of the rigid off.
You'll also have to wrap the 8" to 6" reducers, the foil backed insulation tape (stuff sold for wrapping copper pipes) works great for this. The exterior foil needs to connect to the vapor barrier sleeve on the flex duct. You want this air tight to avoid condensation and sweating in the winter time.
Good point on insulating the filter box. I see hvacquick sells an insulated version though they use different filter sizes, two 14 by 20 by 2 inch merv 13s. I have not yet purchased anything from their site but they've been good about answering questions.
https://www.hvacquick.com/products/residential/Filter-Boxes/Inline-Filter-Boxes/HVACQuick-IFVB-Series-V-Bank-Insulated-Inline-Filter-Boxes
Sorry the picture is just a metal box, where isnit insulated?
It looks like it's on the interior. On the images tab it looks like black foam but they just refer to it as R5 insulated aluminum. I like the idea of adding rigid foam to whatever filter box works for you and then you know exactly how insulated it is, though it's nice to know there's something ready made. When I've asked them questions about other products they answered pretty quickly, but I don't yet have any of their items.
The filters are actually 13.5x19.5 are you sure standard 20x14 fits?
I think that's a question of actual vs nominal size, in that a 14 by 20 is usually 13.5 by 19.5.
Why would you even go for this when AC infitinity filter box is cheaper and fits?
If the AC Infinity filter box you're referring to is the one I link to below, it takes a single one inch thick 14 by 20 filter, which may be fine though it's not insulated. The one I linked to is insulated to r5 and takes two 14 by 20 filters in a V configuration that are each two inches thick vs one. That's why I personally am looking at it, though you may not find many 2 inch thick filters locally.
https://acinfinity.com/hvac-home-ventilation/air-filter-boxes/air-filter-box-with-high-efficacy-filter-8-inch/#product-description
For air coming back to the ERV to be exhausted from the house I'm considering a cheaper filter box that takes a single two inch thick 14 by 20 filter and is priced similarly to the AC infinity box. https://www.hvacquick.com/products/residential/Filter-Boxes/Inline-Filter-Boxes/AirScape-SFB-A-Series-MERV-13-Inline-Filter-Boxes
My sole purpose is to stop using the panasonic ERV filters that cost 130$ canadian per month it gets clogged so fast. To put this ac infinity first then the ERV. Does this need to be insulated? If so is it complicated?
For the fresh air filter I'd probably follow the insulation advice Akos provided in comment #11, adding foil faced rigid insulation to the exterior of the box while leaving the opening accessible for changing filters. Maybe use a strap or 3m velcro for the part you will need to open later for filter changes. The AC infinity box looks like a simple enough shape that adding the insulation shouldn't be too difficult. For insulating the reducers you could use the insulation from some insulated flex duct if you happen to have some that is for 8 inch duct, or get a short piece of an insulation sleeve like here: https://www.supplyhouse.com/HC-Flex-553279-8-x-5-F208-Sleeve-Silver
@acrobatic, for stale return that is fine, but you’d run MERV 8 to 10 only for the return to minimize static loss.
Moving to the larger external filters for both supply and return will not only save on filters, but removing the internal filters will drop power use, likely more than most folks would predict with ECM motors.
If I get the AC infinity, to put right before the fresh air goes into the ERV, does thus box need to he insulated? If yes how would I do this?
talk to your hvac installer and get them to make you a filter box that is insulated. It will be much nicer as the insulation will be on the interior of the box and the cost wont be much more than getting a crappy amazon box and Frankensteining insulation to the outside (would be less messy if it did not have an access panel to change filters). or if you just buy a standard box from amazon you can go to hvac supply house and get 1" foil faced fiberglass by the roll and just make sure to tape all seams up nice. The other option is rigid which i would not enetertain as it seems like a messy way to do it (but could work if you do it right).