Panasonic Intelli-balance 200 MERV filters
Hey guys, so I bought Pana Intelli-Balance 200 about a year ago when they first came out to replace the miserably failed Ultimate Air. I love the unit overall but was really shocked when I saw the online prices for its Merv 13 filter (FV-FL1320VE1). When I bought it on SupplyHosue, they sold it as a pack of 4 for $110, and I was pretty happy with that. They now sell only one filter for that same price, and I was told the 4-pack I bought before was sold to me by mistake. Other online resellers sell the same filter at even higher prices.
Now, the manual and some online sources say the filter is cleanable or even washable. Perhaps those statements are based on the models sold in other markets because the filters I bought are very delicate paper/fiber and even light cleaning seems to ruin the fibers. The manual that comes with the filter itself, says it has to be replaced every 90 days. Considering the price point of the unit itself at around $2800, paying for filter replacement over $400 a year seems a bit ridiculous to me. Am I missing something here? Are there any sources that sell it cheaper? I have not yet seen anyone complain about this, so just asking around.
Thanks.
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I thought the filters for the 100 were expensive at around $42 a pop!
I understand why Panasonic has included these filters (market demand), however they are quite restrictive to air flow which has a real cost in terms of power used by the ECM motors to maintain a given airflow. For less than $400, you can install two external filter boxes which use less expensive (but much better flowing) larger filters. If it was me, I'd just remove the smaller MERV13, and replace with external filters. I'm using a box with a 14x14x2 MERV13 filter, which at 90 CFM measures approximately .05" w.g. pressure drop. The filters are $28 each and last about six months, depending on the air quality.
If the filter is a standard thickness (1/2" or 1") there are companies that make custom filters to your exact size. They are a couple of dollars above standard furnace filters still much less than the Panasonic one.
Another option is to install an external in-line filter box before the unit. You can get these sized so they will take a standard furnace filter which is your cheapest option. The bigger filter also means much fewer replacements, I need to change mine once a year. The filter box on the outside fresh air intake needs to be insulated.
thanks to both, Akos and DennisWood, for the external box suggestion. I was contemplating it before I bought the unit but thought I'd wait and see how the unit performs. So for the box, what would your suggestion be as to the overall size, amount of insulation, etc.? Is there any drawing I can look at? My fresh air intake is a standard 8" Ultimate Air round duct with a hood out of the wall; should I dismantle it and build a new box in place of it? Would 2" XPS liner be enough for insulation?
thanks.
I used R5 but feels a bit on the low side in the north end of zone 5, when it gets cold you can feel that it is fair bit cooler than the house, about R10 would have been better. I would use foil faced polyiso for this, higher R per inch the foil facing is very easy to tape, unfaced XPS is hard to adhere to.
You can buy insulated filter boxes (check HVACquick), their uninsulated filter boxes are cheaper if you don't mind a bit of DIY insulation work. Keep in mind the insulation around the filter needs to be air tight otherwise you'll get condensation on the cool metal surface, simply wrapping it in a layer of fluffy insulation doesn't work.
Thanks, I don't mind DIY work at all, but I see mostly inline boxes on their website. My understanding is that I need something similar to this intake model: https://www.simplyhydro.com/product/kootenay-intake-filter-8/?utm_source=Google%20Shopping&utm_campaign=Copy%20Simply%20Hydro%20Full%20Feed&utm_medium=cpc&utm_term=74504
Also, if I buy an uninsulated version, I need to make sure it's thick enough to fit R10 foam. Did you build your box yourself? Can it be constructed from aluminum sheets and riveted together?
Whichever filter box you pick, I would make sure it takes a standard sized readily available filter. Something like the SFB-V-10x10 or AC-AFB8 is a better start.
Mine is a Fantech FB6 which takes a 10x20x1 filter but it would be too small for your IB200. I wrapped it with 3/4 poyiso on the outside, this is sealed to the vapor barrier sleeve of the duct insulation running to outside and to the ERV.
Starting form a somewhat rectangular box will make insulating it easier. Make sure the filter box itself is very well sealed and is still easy to open to swap filters.
If you have the pre-filter on the outside fresh intake, you can take the internal filter right out, but I would replace the one inside the unit with a washable foam filter just in case.
What climate zone are you in?
I'm in Southeastern PA, near Philly, so just crossing into zone 4.
Why would you use two filter boxes, how do you connect them? just inline? My space is somewhat limited there.
There is a filter (not MERV 13) on the stale air side as well which also restricts air flow. It's just there to keep the core clean. So you if had room, you could replace both the stale air and fresh air side with external boxes. The stale air side (air from your house) is only filtered to keep dust out of the ERV core. If that stale air side filter is washable, and/or inexpensive, just leave it.
Zone 4 is not so cold, so if you build a vent box on the cold/fresh air side, 1" of EPS would be fine...the ERV box itself likely has less than 1" of insulation.
It's easier to replace the ERV's intake MER13, with say a cheaper MERV 8-11 (just to keep dust from the core) and put a filter box on the warm side of your fresh air supply with a larger, cheaper, better flowing MERV13 filter. This way you don't need an insulated box. I am using the 6" version of this:
https://www.hvacquick.com/products/residential/Filter-Boxes/Inline-Filter-Boxes/HVACQuick-CFB-Series-MERV-13-Inline-Filter-Boxes
I have a fully equipped shop, but honestly it made more sense to grab one of the CFB series, particularly as the flow characteristics are known, and they are fairly compact. If I had a lot of room (I don't) I would have built a much larger box and used a Filtrete 1900 in 16x20x1 flavour.
Thanks, Dennis
I've attached my setup here to clarify a couple of things...
- I do have a stale air washable filter (on the right), so I will keep it as is.
- My fresh air intake is a legacy 8" insulated flex duct from UltimateAir installation. The original installation itself had a lot of flaws, so I had to rerun some ducts and over-insulate the flex to avoid condensation. I now have a 8/6" reducer at ERV's intake terminal (red circle). I was thinking I could cut the flex somewhere close to the terminal, add another reducer and insert a filter box in between. Not sure how much space I'd have there but I might be able to fit a larger Filtrete box.
A couple of questions:
- Since the duct is insulated, do I need extra insulation inside the filter box or just a reflective bubble liner would be enough, maybe, or nothing at all? The CFB box construction seems pretty tight not sure how to insulate it without seeing one.
- If I go with the filter box you suggested in the link, how long do you think the filter would last?
- What are your thoughts on CARBON IMPREGNATED FILTERS they sell? I do have neighbors with wood-burning fireplaces and the fumes enter the system sometimes. Would a thin carbon filter on the exterior hood help at all if changed, say, monthly?
thanks!
If you put the filter box on the cold side, you'll see condensation in colder weather anywhere it's not insulated, just like your intake duct. It's easier to put it on the warm side for that reason if you have room. You could just use another washable pre-filter installed on the fresh air side inside your ERV. The six inch version of that FB box can connect directly to your ERV if you go that route on the stale, or fresh side. Try and sort it on the warm side if you can.
I've testing a few carbon impregnated filters, and actually have a supply of 14x14x2 for my inline filter box. I don't think it's possible to fully address smoke for any extended period (like beyond a week or two) with a single filter like this due to the low volume of carbon on the filter media, and the short exposure time for air going through the filter. I did fab up a very temporary outside hood for my old ERV intake (only 30 CFM) and it did make a difference using just off the shelf carbon filters sold for kitchen exhaust hoods during periods of high wildfire smoke.
I did test one of the 14x14x2 MERV13 filters after about 3 months of winter use for pressure drop. There was only a very minor difference compared to a new one. I figure 6-8 months for replacement. Keep in mind that I have a washable pre-filter in the HRV that is MERV6-8 at best, but it does filter outside air before it hits the HRV core, and then the inline MERV13 filter box on the warm side. These smaller filters, even crappy ones, do make quite an impact on air flow...easily twice as restrictive as the 14x14x4 filters.
My current "solution" for smoke is an 8"x 24" carbon filter from Terrabloom:
https://terra-bloom.com/products/terrabloom-premium-carbon-filter-8-by-24-750-cfm-australian-carbon-top-rc-48-class-1-8-thick-bed-carbon-air-scrubber-for-indoor-gardens-grow-tents-hydroponics-odor-and-smoke-elimination
The 4" version I tested with my HRV setup was too restrictive dropping flow by .1-.2 in w.g. The 8" version is 24" long and has 15 lbs of activated charcoal....enough to deal with smoke at my typical vent volume of 75 CFM. I have not tested actual pressure drop with that setup yet.
I used the aforementioned smaller 4" version of this type of filter to address a smell issue with my daughter's chameleon habitat (the live cricket/food habitat stinks!) and was pretty astounded with how well it worked. Once I sort a decent mount for the 8" version, I'll post here about it. It's not just wild fire smoke, but back yard camp fires and skunks (we have a family of them under our shed) that can be smell challenges :-)
Thanks again for such a diligent explanation. I don't have a terrible smoke problem, just an occasional smelly air from a neighbor. I think I can use a thin layer of the activated charcoal filter inside the exterior hood (changed monthly) to mitigate the issue during cold months. My only remaining question is about "washable pre-filter installed on the fresh air side inside your ERV". Those are just light dust filters; do you think it's enough to guard the core? Otherwise, it's a straightforward install, and I think I might have enough space on the warm side to insert a larger than 14x14 box.
No worries...glad to help :-)
You just want to keep dust/larger particles out of the core. If you think about it, the stale air washable filter is there just for that reason on one side of the core, so replicating it on the other side will be fine. The filter Panasonic uses on the smaller FV-04VE1 is pretty much just a washable foam deal on the fresh air intake, and just a single layer mesh screen on the stale air side...worked fine for five years before I removed that unit.
Depending on air flow settings for your ERV, the outside charcoal will make a difference, but won't address odours 100%. If you pick up a few of the 14x14x4 charcoal filters to use in summer, and combine that with charcoal media in the hood, it will for sure make a significant difference. Just be aware that the 14x14x4 charcoal impregnated filters are MERV10, not MERV13 like the non-charcoal versions HVACquick sells with these boxes.
There is not a ton of research out there on carbon filters vs CFM requirements, vs measured VOC reduction as they would relate to HRV/ERV, but I did see one recommendation for a minumum of 5lbs of activated media as a good start. I found the AC Infinity 4" carbon filter was (very subjectively) in the range of 80% reduction in smoke smell (literally burnt some wood at one end of my test bench) at 90 CFM. It has somewhere around 4lbs of carbon inside. The Terrabloom 8"x24" filter has 15 lbs of activated charcoal and is obviously much larger, so incoming air will have much longer contact with the charcoal at 90 CFM vs the 4" filter.
Sadly, wildfire smoke is likely going to be a bigger issue going forward, particularly for those of us surrounded by boreal forest in a hotter/drier climate.
I forgot to mention, but you may want to have the balance checked on the unit once you set up a lower resistance filter setup. It's supposed to balance itself, but it's always good to check in case there is an unusual resistance somewhere in the system. Something like a stuck damper on the exhaust hood etc.
Completely agree that the $400/year in filters is outrageous. I own this unit and can't recommend it - seriously evaluate the total cost of ownership of any ERV and don't trust the vendor to have reasonably priced filters. Some have outrageous pricing.