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Community and Q&A

Northern Climate HRV/ERV Recommendations

mattbrennan4 | Posted in Green Products and Materials on

Hi All,

Forgive me if its been covered, but having read through multiple articles on northern climate HRV systems and despite some great conversation there seems to be a lack of consensus what some of the best high efficiency options are.

Actually, I take that back – the consensus seems to be the Zehnder units ($$$$). 

What I am talking about is second best and perhaps more readily available to the masses. My primary metric that I would like cold climate efficiency. If anyone can provide recommended CFM target for the unit, that would be bonus. Efficient ECM motor and defrost – well that’s gravy.

To give some context, here are the details of my project:

– deep energy retrofit project
– 1900 sq ft 2 story home, existing 6″ ribbed insulated ductwork
– built in 1941, full reno in 2001 (code min)
– Halifax, NS, Canada
– Heat Pump/Basebaord heat
– HRV located in an insulated basement (R35)
– existing unit is a power hog and 55% recovery listed

Any and all comments welcome as I hope this post ends up benefiting more than just myself. Thank you!

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Replies

  1. user-2310254 | | #1

    Hey Matt,

    Panasonic’s IntelliBalance comes in a cold-weather version (althought it’s an ERV). It is affordable compared to Zehnder is my understanding. No doubt others will chime in.

  2. charlie_sullivan | | #2

    For the CFM, I think there are two options. One is to size it just right, and the other is to oversize it and use it on boost for bathroom exhaust.

    For sizing just right, an option is to measure CO2 with the setup you have and see how it's doing. If you like the results, get something similar...although if your other retrofit work includes a lot of airsealing you might want more airflow.

    Of you can go based on code or other general guidance, based on sq. ft. and number of bedrooms (as a proxy for number of occupants).

  3. mattbrennan4 | | #3

    Thanks, Steve. I'll add it to the list for the benefit of others as well.

    So far, using two different methods, I get 67CFM or 107CFM, quite the difference. I understand many ECM motors allow this to be adjusted which I presume limits the waste factor for oversizing.

    Another factor I'll add to consideration is max MERV filter no. Ideally would like to see 13 or better, though many are not there (at least as stock).

    Here's a couple options I am looking at:
    Venmar/Broan - https://www.venmar.ca/133-air-exchangers-x24hrv-ecm-new.html - looking into now
    Lifebreath - https://www.lifebreath.com/product/lifebreath-205-max-residential-heat-recovery-ventilator-hrv/ - unclear if this has an ECM
    CERV2 - https://buildequinox.com/files/CERV2/CERV2_brochure_012221.pdf - interesting product, unsure of cost
    Fantech - all models seemed to lack the performance I am looking for
    Panasonic Intellibalance - https://na.panasonic.com/ca/home-building-solutions/ventilation-indoor-air-quality/energy-recovery-ventilators-erv/intelli-balancetm-100-50-100-cfm-0 - not an HRV, not ECM, but interesting

    1. charlie_sullivan | | #4

      There's no penalty for oversizing other than cost, once you have an ECM. The fan power to move 67 CFM will typically be lower in 150 CFM rated unit set to <1/2 air flow than in a 75 CFM unit set to 90% air flow, the noise will be lower, and the heat recovery better.

      I'm a CERV skeptic. An HRV gives you some heat recover "for free", but with CERV, any heat transfer is active--you need to pay for it. Otherwise, your list has good ones to consider, but I don't know any better than you which are best.

      1. JHCT | | #12

        Hi Charlie.
        The description of the heat transfer in a CERV being active is something I haven't heard before. Can you share any info or links you might have regarding this?

        Thanks.
        -J

        1. lance_p | | #24

          Heat recovery in the CERV is done with a heat pump. It's very effective, but the unit needs to be running whenever it's recovering heat.

          CERV:
          https://buildequinox.com/thesystem/

          And a similar system from Minotair:

          https://www.minotair.com/minotair-pentacare-v12_en/

  4. Expert Member
    AKOS TOTH | | #5

    The Panasonic unit does have ECM blowers. For the money and performance, it is the best unit on the market.

    There is no problems with using an ERV in cold climate, in some ways it is better as it they tend to ice up less so the unit spends less time in defrost mode.

  5. this_page_left_blank | | #6

    Don't buy any unit smaller than 200cfm.

    The second best would probably be the vanEE G2400, or its Veneer or Broan variants. It's not significantly cheaper than a Zehnder however, if you're coming just the unit cost and not the ductwork (which you already have).

    1. lance_p | | #7

      200+CFM for a 1900 sqft house?

    2. mattbrennan4 | | #10

      What's the logic on the 200cfm? Thanks!

      1. this_page_left_blank | | #27

        I'm making an assumption that your house will have more than two people living in it. The square footage plays no role in how much CO2 is generated. (Yes, there are other air contaminants that are more dependent on house size, but CO2 is the dominant one when it comes to deciding equipment size in most houses. With an extremely large house, square footage might become more important.)

        From my experience in my own house, using continuous CO2 monitoring, around 100cfm is good for two adults and two small kids, but no more. If we have dinner guests, just adding two more adults means the HRV cannot keep up. And it doesn't take long, either. CO2 goes from around 650-700ppm to close to 1000ppm well within 2 hours. I have the CO2 monitors wired to the HRV so that it boosts when it goes above 900ppm. Even at an estimated 250cfm, it takes a long time to bring the CO2 levels back down. I really wish we had 350cfm available (the HRV is capable, but the ducting is not). High particle count from cooking events also take forever to clear out. Having a good range hood setup can help with this, but only partially. A range hood will do little to ameliorate particulates coming from inside the oven. And yes, this is significant. I've seen levels of 250uG/m^3 after using just the oven.

        This is why I think you can't go too big on an HRV (or ERV). For a three bedroom house, count on a continuous rate of about 100cfm. And you must be able to boost at least 50%, but more is better. The only caveat is that it has to have multiple speed settings, and the minimum has to be well below your expected continuous rate.

        1. mattbrennan4 | | #29

          Interesting points on CO2 values and air quality. The big picture would be to have both - air quality & a low energy penalty. You would think when comparing products, manufacturers would consider/market these factors more. The ECM motor would seem to limit the energy penalty.
          Q: for your system, what unit did you use and also, how did you go about wiring your CO2 sensors to work in tandem with the unit?

        2. lance_p | | #38

          Interesting observations Trevor, thanks! I have thought about how CO2 levels vary with occupant load (like while entertaining, as in your example) but have yet to do any reading on it. A good reason to have some additional capacity.

          1. Expert Member
            Michael Maines | | #52

            It looks like we're going to use this Panasonic unit for a 600 sf ADU I designed. We only need 36 cfm continuous but can't find another cold-climate unit that will do the job, and we certainly don't need 200 cfm. But most houses are larger than 600 sf.

  6. lance_p | | #8

    I've been intrigued by the Panasonic Intellibalance ERV for quite some time, and now there's a 2nd generation model that comes with a boost function:

    https://na.panasonic.com/us/home-and-building-solutions/ventilation-indoor-air-quality/energy-recovery-ventilators/intelli-balancetm-100-balanced-air-solution-cold-climate-erv-50-100-cfm

    It's only 100CFM even when in boost mode, but for a smaller house it would work just fine. It's a very affordable option, has independently variable ECM motors, and industry leading (as far as I can tell) moisture transfer which is important in a cold climate and a reason you may want an ERV over an HRV (unless the house is small, super airtight and has high occupancy).

    ERVs can also have an advantage over HRVs in hot, humid weather when air conditioning is being used since they transfer some of the incoming moisture load to the drier outgoing air, reducing the latent load in the house for a given amount of ventilation.

    Food for thought.

    EDIT: I just checked the moisture transfer on the Zehnder ComfoAir 200 ERV variant and it's right up there with the Panasonic, maybe even a little better.

  7. alex_coe | | #9

    +1 to what Akos said.

    I would suggest 2 of the Panasonic ERVs though. One per floor. I bought 2 of the new ones (VEC2 for colder climates) when I saw they added the boost function and IMO the performance & build quality for the price are unbeatable.

  8. AlexPoi | | #11

    Venmar has a new auto balancing line that seems high quality.

    As for the power, most ERV/HRV have different speed settings. Choose a device with a middle speed matching your target numbers so you can boost it when you need it. Based on the size of the house, I would aim to buy something in the 140-150 cfm max range. It should be more than enough.

  9. frankcrawford | | #13

    Look at Tempeffs new RGSP-k ERV unit, no preheating down to -40 using its dual alternating core technology.
    https://www.tempeff.com/wp-content/uploads/2020/11/Tempeff_RGSP-K_Sellsheet.pdf
    https://www.tempeff.com/

    1. lance_p | | #19

      Interesting. Works on the same principle as the Lunos fans (thermal mass core and reversing airflow), but uses a switching damper to reverse airflow instead of reversing the fans themselves.

      The only potential downside I see to this is a non-linear relationship to outdoor temperature and latent energy recovery. Since latent recovery is based on condensing moisture out of the exhausted air, the outdoor temperature will determine how much moisture can be recovered:

      With indoor conditions at 70F and 30% RH (dewpoint of 37F) latent recovery will approach 0% @37F and warmer and the unit will act purely as an HRV. I find it odd that the latent recovery data is not advertised in this press material. "Up to" 70% latent recovery... I wonder what the ideal conditions would be to get to 70%?

      I can't find Tempeff listed in the HVI database, and they don't claim HVI certification. Does anyone know if they've been tested by a regulatory body?

      1. this_page_left_blank | | #28

        Yes, it's interesting but I have some more reservations.

        -the technical info they provide is very sparse. This is a potential red flag
        -they only have two speeds; I would say three should be the minimum; they do have 0-10V fan control, which is great, but most people aren't going to use that
        -the minimum fan setting is too high relative to the maximum
        -it's rather large, and odd shaped. Fitment would require consideration during design phase, and could be very difficult in a retrofit scenario

      2. Jon_R | | #31

        > latent recovery is based on condensing moisture out of the exhausted air

        Where does this come from? You don't generally need condensation to move moisture.

        1. charlie_sullivan | | #34

          They have two different core types, only one of which is coated with a desiccant for summer moisture transfer. https://www.tempeff.com/wp-content/uploads/2020/06/Tempeff_DUAL-CORE_US.pdf ~50% latent recovery. But it might be that that coating is only available in their commercial scale models.

        2. lance_p | | #39

          The Tempeff unit uses core A to warm incoming air and core B to absorb heat and collect moisture from outgoing air. Once the cores are approaching their relative "ambient" conditions (i.e. they cannot absorb or give off any more heat) it changes the airflow direction so it is using the heat stored in B to warm incoming air and A to absorb heat from outgoing air.

          Warm outgoing air deposits moisture in (condensing on the surfaces of) the cold core through which it is passing, but this can only take place if that core is cooled to below the dewpoint temperature of the outgoing air. This depends on the outdoor air that was flowing across it before the direction of flow was reversed. Lunos fans work the same way.

          The Tempeff doesn't use a conventional cross/counter flow core with a vapor-open membrane separating the airstreams. It uses two completely separate airstreams that pass through a "core" who's thermal mass is responsible for the recovery of heat/condensed moisture. As Charlie points out, they also offer an optional desiccant coating to improve moisture recovery.

          An interesting take on the recovery ventilator concept.

  10. exeric | | #14

    I favor the Panasonic like others do. It's only limitation is that its only 100 cfm max, which makes it iffy if you have two or more bathrooms with a shower. Also, that 100 cfm could be a limiting factor depending depending on occupancy of the house. Finally, a single ERV is problematic to plumb the ducts efficiently in a two story house.

    I think the best answer is to get 2 Panasonic ERVs. They're only about $11oo each or $2200 for both. You could plumb the ducts so that you get the best volume of air for each bathroom and you will be able to have the shortest length of ducts if you can place each ERV separately. That will improve their efficiency. Have power to each wired into separate wall switches so that the ERV supplying the bedrooms remains on while the other ERV is turned off at night. That will also improve efficiency.

    Finally, make sure to use a CO2 indicator to find out what each ERV's CFM is required and dial them down individually to match their need. The Panasonics have that capability. Have each bathroom connected to its own ERV exhaust and the fan boost function switch in each bathroom wired to its own ERV. I think you'll be happy with that setup.

    EDIT: I don't think the outside air input to the ERVs needs to be in conditioned space. That will be cold outside air in that duct. That duct and and any filter box associated with it needs to be insulated from the conditioned space.

    1. mattbrennan4 | | #20

      Thank you, as a follow up question - for installing two ducts, I presume this mean an additional two penetrations in the envelope or are you suggesting the second system links up "in-line" with the other unit.

      Secondly, with existing 6" ribbed ducts that are not very straight or well installed, any comment on how much this will hurt the cfm performance?

      1. exeric | | #35

        I think you could get by with one penetration from outside for the "IN" air. With a filter box within the house structure or outside it Then wye two ducts on the output side of the filter box going to each ERV if you decide to get two ERV.. If you have two ERVs they would run more efficiently if there is no commonality of ducts from them and you would eliminate any possibility of backflow from one ERV to the other that way. Two "OUT" air penetrations would probably be better to eliminate that possibility. Not sure.

        I have 6 inch flex ducts connected to my single Panasonic ERV and it doesn't seem to have taken a hit. The biggest improvement was going to a larger outboard filter and plenum I was able to turn down the fan speed after doing that for equivalent CO2 measured. Just use common sense about sharp bends in flexible ducts and go as straight and direct as the house structure allows.

    2. mattbrennan4 | | #23

      Another question, as for a control for the Panasonic Intellibalance, is there a wall control unit that you know or recommend to be compatible? The Venmar in the list I posted above has a linked one, but I cannot seem to find that for the Panasonic. Thank you.

      1. exeric | | #36

        I don't think so.

    3. drafthunter | | #80

      Which CO2 sensor are you using with the Panasonic ERV and how do you have it integrated?

  11. exeric | | #15

    One added thing to think about. Filter are expensive and very restrictive for ERVs. Because you would have 2 of them it makes sense to avoid the needs for Panasonic's small restrictive filters. Something to think about would be to have a very large 8 or 10 inch diameter common intake duct for both ERVs coming from outside. Plumb that to a large filter box made for a commonly made furnace filter. The box doesn't need to be close to either ERV but it needs to be easily accessible. Then have normal 6 inch ducts wye off the filter box output to the input of each ERV. You will save a fortune in filters over time doing it that way and it will also improve the efficiency of each ERV by using a very large filter box and filter.

    1. lance_p | | #16

      This is exactly what I had in mind, and in fact I'm looking for a way to mount this filter box outside so the filter is super easy to access and the ductwork never has dirty unfiltered air flowing through it (keep the ducts clean). Ideally this filter will be bottom-fed so gravity is working against contaminants in the air, and large debris will fall off the filter during periods of lower airflow keeping restriction low.

      Good 16x25 furnace filters are SUPER common (in my area at least), can be purchased on sale very reasonably and will flow many times more air than the tiny proprietary filters most ventilation units use. This should reduce the power consumption of the ventilator (saving $) and lengthen the service life of the fan motors.

      1. exeric | | #18

        "This is exactly what I had in mind, and in fact I'm looking for a way to mount this filter box outside so the filter is super easy to access and the ductwork never has dirty unfiltered air flowing through it (keep the ducts clean)."

        Good idea!

      2. pnwbuilder | | #37

        I am planning to do the same thing. One extra benefit of placing the filter box outside is that it doesn't need to be insulated to prevent condensation.

        1. lance_p | | #46

          Yes, that too! Insulating a box with a removable filter could be a pain.

    2. mattbrennan4 | | #21

      I like this idea. Any recommended filter box products you suggest that would work here? Am I fair to assume that you would simply remove the filter from the HRV as this would now be redundant?

      1. lance_p | | #25

        I have yet to come up with a solution, though I haven't spent too much time looking yet. It may end up being a custom made piece unless I can find something suitable (a painted plywood box that fits into the look of the house maybe?).

        There are likely options in the furnace ductwork catalogue but they will all be some sort of thin bent metal product that may not be suitable for outdoor use.

      2. lance_p | | #26

        And yes, if I'm confident that the outdoor filter is doing a good job then the interior filter in the ERV would be unnecessary. Leaving it in for piece of mind would always be an option, and if the outdoor filter is doing a good job the ERV filter would never need changing. The energy penalty of the additional filter would likely be very low if/when running the ERV at less than full speed.

      3. Wannabegreenbuilder | | #43

        Hello, I am in the process of putting in a whole house system and have bought a galvanized metal filter box that has “clean comfort indoor air essentials” written on the front door. 1-800-267-8305 is on another sticker for questions. I got it from my Local HVAC subcontractor. It came with a MERV 11 20 x 25 x 5” filter but I’m sure a guy could put other qualities of filters in it. I hope this helps.

        Andy

        1. lance_p | | #48

          Hey Andy, thanks for the info! Looks like they offer a few nice looking options in decent quality higher gauge metal. Does your model look like any of these?

          https://www.cleancomfort.com/products/filtration/media-air-cleaners

          If you don't mind me asking, what was the cost of your filter housing?

          1. Wannabegreenbuilder | | #56

            Hi, it looks similar to the AM11-5RA. I don’t know price as I got it in a hard bid that was not fully itemized.

  12. Expert Member
    Michael Maines | | #30

    I'm not sure if anyone mentioned that in cold climates you need to be sure that the ventilation system will continue working when it's cold out. Different units have different ways of dealing with it, and different shut-off temperatures.

  13. mattbrennan4 | | #32

    I've decided to go with the Panasonic( https://na.panasonic.com/us/home-and-building-solutions/ventilation-indoor-air-quality/energy-recovery-ventilators/intelli-balancetm-100-balanced-air-solution-cold-climate-erv-50-100-cfm).

    Bang for buck it is number 1 as of today in my market. Lacks some modern features like monitoring app/control levels but still no. 1 as far as I can tell.

    After reaching our to local HVAC locations, all of which somewhat surprisingly said they do not sell/manufacture/install plenum boxes for filters, I'll be purchasing the upgraded merv 13 filter.

    That said if anyone has a recommendation of where I could find a plenum to link up with a 6" in/out. Please let me know.

    1. kevin_in_denver | | #33

      Matt,
      Please let us know what the installed cost of this turns out to be.
      If it's DIY, please try to estimate what a contractor would charge.
      Much Appreciated.

    2. Expert Member
      AKOS TOTH | | #41

      I use a Fantech FB6 filter box. Comes with a merv13 filter, good for around 100CFM.

      It is un-insulated, but if needed, it would be pretty simple to wrap it in some rigid. Mine is after the ERV unit, seeing how much crud ends up in it, I really whish I installed it before the unit.

      The high MERV/HEPA filters in most ERVs are actually pretty restrictive. You can probably reduce the energy consumption of the unit by 40% just by swapping it for a washable foam filter+large external filter.

  14. Wannabegreenbuilder | | #40

    Perhaps, if it is too good to be true ... it is! I am contemplating buying a “magic box” like CERV2 by Build Equinox. There are others too now. However expensive and complex (difficult to service?) theY make good sense to me on paper anyway. Europe seems to be moving in this direction also from what I read. You might want to check this out however I do not think you will find this a budget friendly solution.

    1. lance_p | | #49

      I like the idea of these "magic boxes", with one issue: they don't recover moisture, so their use in a cold climate could require supplemental humidification (depending on the house, occupants and moisture load of course).

      Other than that they seem pretty handy and could cover some level of heating and cooling during the shoulder seasons in many areas, as well as dehumidification in the summer months.

      1. Wannabegreenbuilder | | #54

        It has been suggested before on GBA that houseplants in a cold dry climate work well to humidify and reduce CO2. If the house is tight I would tend to believe this but since I can’t keep a cactus alive I can’t report from experience.

  15. kevin_in_denver | | #42

    According to a recent paper,

    "At the primary first cost of $1,500, HRVs are cost effective in climate zones 7 and 8. At a lower cost (assuming minimal installation costs) of $500, HRVs are cost effective in zones 5, 6, 7, and 8.Dec 18, 2018"

    https://www.osti.gov/servlets/purl/1488935#:~:text=At%20the%20primary%20first%20cost,6%2C%207%2C%20and%208.

    I believe it's pretty hard to find an HRV installed cost of under $1500.
    Given the fact that less than 5% of homebuyers are even interested in having one, I don't think an HRV adds any resale value.

    Solar is really the only hardware ingredient in a house that has been falling in cost. So my advice is forget the HRV and add some solar.

    1. Wannabegreenbuilder | | #44

      As houses get tighter, the need for clean filtered air to replace indoor pollutants from cooking, breathing and other volatile gases caused by things we put into our houses becomes more important. Financial concerns are important, but what is your health worth?
      Andy

    2. Jon_R | | #45

      I think DOE is concerned with cost and energy, where it's valid to consider alternatives. But there is more to it. Does "forget the HRV" provide the same CFM reliably supplied to and exhausted from the same places and provide the same "no cold draft" and "not too humid (think ERV)" comfort?

    3. creativedestruction | | #47

      Kevin,

      I wouldn't hold too firm to those figures, or to yesterday's homebuyer expectations. I barely trust my own energy model assumptions, to say nothing of the DOE. Their flat cost-effectiveness statements can't have accounted for the current and future cost of electricity everywhere or the relationship between cost and SRE.

      ...And trading an HRV for PV sounds something like trading a window for a dog.

      1. Expert Member
        RICHARD EVANS | | #63

        "...And trading an HRV for PV sounds something like trading a window for a dog."

        😂😂😂

    4. lance_p | | #50

      All the solar in the world will not replace the need for ventilation in a tightly built house.

      1. Expert Member
        Michael Maines | | #53

        If the market value drove every house design decision, we would all live in unsafe homes. ASHRAE-compliant ventilation is a health issue, and therefor a life safety issue, just not one as obvious as fire safety.

      2. charlie_sullivan | | #57

        I think the implication was that you could provide mechanical ventilation without heat exchange if you had enough low-cost energy to heat the incoming air. Do to so without cold drafts is the real challenge, as Jon notes. You could add electric heaters on the supply air, but that hardware still costs money, and if you are going spend money on hardware, you might as well get HRV or ERV and get the same heating for free.

    5. mattbrennan4 | | #65

      I'm just going to say that I disagree. Perhaps in your region, but not where we live. HRV/ERV's are exceptionally important. I'm all for solar, but that is not the topic being discussed here.

  16. kevinbmn | | #51

    Suggest consider a unit with elements that facilitate three main concerns A] installation 1) duct-within-duct-single termination and B] commissioning: 1) access door with pressure measuring ports, 2) balancing dampers and C] operation 1) ECM motors, 2) HEPA filter, 3) built in interlocked electromechanical dampers.

    1. Wannabegreenbuilder | | #55

      Kevin, in your opinion what is the most cost effective solution to these main elements in his climate zone?

      Andy

      1. kevinb15 | | #70

        Regardless CZ, imho - Broan/Venmar family appear to provide all of these elements in One Box and deliver desired performance w std. service. Note - concentric/dual hood termination is an engineered solution available from several mfg's; and may be limited to 120-135cfm at under .5 " wc pressure.

    2. this_page_left_blank | | #61

      It's recommended to keep the exhaust and intake at least 6' apart, ideally 10'. Having one envelope the other seems like a bad idea, both from air contamination standpoint and less importantly an efficiency standpoint (unless the inner tube is well insulated from the other).

  17. kevin_in_denver | | #58

    I'm not advocating against ventilation.
    I'm saying ventilate with couple of bath fans and forget the HRV
    In my opinion, even 150 cfm exhaust will not produce a noticeable cold draft anywhere in a 1200-3000 square foot house with a sub 3 ACH 50 blower door test.
    Again, an HRV doesn't add to the resale value of the house, and all the filter maintenance will just annoy the homeowner.

    1. Jon_R | | #59

      What will a closed door bedrooom CO2 level be when using a couple of bath fans?

      1. kevin_in_denver | | #73

        I can understand the desire for fresh air when sleeping.
        Lunos is the best and lowest cost solution. https://foursevenfive.com/lunos-ego/
        But be aware that this $1000 total investment will not pay for itself nor be recouped on resale of the house. Nor have I seen convincing evidence that spot ventilation will improve your health.
        Cracking the window is the cost effective thing to do.
        If the bedroom door is left open, Fick's Law of Diffusion rules, meaning that the bath-fan-whole-house-ventilation is sufficient. (The average speed of an air molecule flying around the house is 500m/s which means it only takes minutes for the air quality to equalize in a house)

        1. creativedestruction | | #84

          "Fick's Law of Diffusion rules, meaning that the bath-fan-whole-house-ventilation is sufficient."

          You run your bath fan all night?

          "The average speed of an air molecule flying around the house is 500m/s which means it only takes minutes for the air quality to equalize in a house)"

          How did you arrive at this number or this supposed quality? In absence of mechanical force, stack effect, or other significant source of pressure differential, Fick's Law tells us diffusion is REMARKABLY slow at equalizing the distribution of air given a roughly isolated system, e.g. a tight house. It says nothing of "average" air molecule speed and certainly nothing of "quality". A closed bedroom door dramatically reduces equalization and distribution no matter how many CFM you suck out above the toilet.

          And Lunos is far from lowest cost through-wall HRV/ERV paired system.. do a little research and you'll find similar products with slightly lower efficiencies at half the unit cost.

    2. this_page_left_blank | | #60

      Not only will this plan not provide fresh air where and when it's needed in the best case scenario, where is the makeup air even coming from? In a well air sealed house, you're just going to depressurize the house with no significant air going in or out.

      1. kevin_in_denver | | #74

        "you're just going to depressurize the house with no significant air going in or out."
        A Panasonic bath fan rated at 80 cfm will move 80 cfm. Today's best sealed houses (with 10+ door and window assemblies) simply cannot prevent that. If you really need to ensure that the 80CFM of fresh air is filtered on the way in, there are cheaper ways than a $2k-$8k whole house HRV system.
        https://www.greenbuildingadvisor.com/article/are-hrvs-cost-effective

        1. exeric | | #76

          You are incorrect. Have you heard of cavitation by a propeller (or fan). I had a Panasonic bath fan and went through everything you are suggesting and it did not work in my 2.25 ACH50 house. Finally went to an ERV. Couldn't be happier.

  18. user-2310254 | | #62

    I think I understand Kevin's point (but he can correct me if I'm off base).

    If ERV/HRVs are not required in a jurisdiction, few appraisers are going to include this cost when calculating home values. I assume this is something production builders have to keep in mind when budgeting new projects.

    For my part, I put an ERV and dehumidifying ventilator in my last 1.5 ACH/50 home. When my new build gets going, I'll install mechanical ventilation in that one as well. It's a cost I'm willing to absorb because I want to waste less energy and breath in fewer indoor pollutants.

    I imagine most GBA members have similar concerns and ways of rationalizing their decisions.

  19. PAUL KUENN | | #64

    If you're not on a busy road, the Lunos from 475 always wins up here in northern Wisconsin. The highest rating of all HRVs and no duct work. I do have customers put the covers on and turn off when it's colder than -5 below zero F.

    1. mattbrennan4 | | #66

      these are interesting units as well and I am thinking of using a set in our detached garage. How cold can they perform is the question and it condensation an issue, a few days a year we will often hit -30c but its rare. If they can't work in those conditions they become less appealing.

      1. kevin_in_denver | | #75

        Here's a nice economical solution for an unheated attached or detached garage:
        https://www.homedepot.com/p/VENTS-MA-Series-6-in-Duct-158-CFM-Wall-Through-Garage-Ventilation-Kit-VENTS-GK-150-MA/301368524
        Control it with a $20 timer or motion sensor.

  20. mattbrennan4 | | #67

    Panasonic intelliblance for Cold Climates arrives Monday, Ill try to update to close the loop here.
    BTW - cost delivered in CAN was ~$1375 (tax not incl).

    1. AlexPoi | | #68

      Where did you order it? The local shops only want to sell to registered contractors here.

      1. this_page_left_blank | | #69

        I seem to recall seeing it on Amazon. Gasexperts.CA sells multiple different brands, but not Panasonic.

        1. AlexPoi | | #78

          Yes love this website. Their price are pretty good and I can't buy most of their stuff locally.

      2. mattbrennan4 | | #71
      3. mattbrennan4 | | #72

        I ran into that issue a lot too. As a manufacture of another product, I can understand not wanting to sell to DIY, but at the same time, times seem to be changing rapidly.

        1. AlexPoi | | #77

          Thanks for the link Yeah I don't understand it either. It's only the hvac stores that are doing this in my area. I never had any problem buying from the electrical or plumbing supply houses. Probably because they are afraid of homeowners messing with refrigerant or calling to ask questions...

  21. mattbrennan4 | | #79

    Just to close the loop - the Panasonic Intellibalance Cold Climate has been installed. Results seen to be immediate. Currently I am dialling in the settings. I have it set at 60CFM in/out with a balancing meter on its way to confirm more precisely. I am also only running it 20 on 40 off. No issue with condensation on windows and humidity reads ~40% so still on the lower end for Feb. Quite pleased so far with the biggest differences noticed are the lack of freezing air coming in from the old unit which has no speed control and operated at 54% eff. (probably less). Home comfort wise in Canada.... its a big difference.

    1. drafthunter | | #81

      How loud is it? Do you think it would be too loud to run in a bedroom closet?

  22. CheeseCurd | | #82

    Hey Matt, just wanted to follow up on this thread to see what your final settings were? Also curious how you determined the on-off time settings. My assumption was that since ASHRAE 62.2 recommendations are for continuous ventilation, that you would be running continuously. I’m planning a new 2200 ft2 home and trying to choose my ERV. I read in another GBA thread about a possible Panasonic Intelli-Balance 200 in the works… hoping that will be an option.

  23. dcfortin | | #83

    Does anyone have experience using the Panasonic Intelli Balance 200 for cold regions?

    Thanks

  24. lance_p | | #17

    Ontario too! :)

  25. mattbrennan4 | | #22

    This group (and previous articles) make me feel better about going the ERV route, but locally, the efficiency groups tend to recommend HRV's. Where's at Dana Dorsett when you need him?! (haha!) I'm attaching a photo of the climate averages for my area. If anyone wants to take stab at this, it's much appreciated.

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