Spot ERV/HRV Side Effects: Why I Avoid Lunos or Panasonic All-In-One Ductless Ventilation

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We tend to get focused on products instead of systems when we're trying to solve our problems. Unfortunately, there is never a silver bullet or a simple answer to most home performance challenges.
Here's why the spot ventilation and switching HRV/ERV products out there won't properly ventilate in most airtight homes out there: they don't create a reliable pressure imbalance within the home, which you need in airtight homes because you can't use one-way exhaust fans ( • Borderline of Balanced... ) except in the kitchen ( • 3 Rules for Kitchen Ma... ).
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[@HealthyHomeGuide]

Thanks so much Corbett! I really appreciate you discussing my DIY HRV. Not only that, but this video was full of invaluable information on which systems to avoid. Love it, as usual.

[@HomePerformance]

Heck yes Alex, keep up the great work

[@steventocco4579]

So cool to see you highlighted in this overview

[@HealthyHomeGuide]

@@steventocco4579 hell yes.

[@arjungupta-inventor-iaq]

Thanks Corbett for the amazing video.

[@HomePerformance]

Glad you enjoyed it!

[@oemca1919]

Your mic is on point! I’m gonna applaud you for that. You got like ASMR podcast thing going on.

[@connorgarrett7064]

Hey Corbett. Remember me? I bought 32 lunos fans for my project! The bath fan was always an issue in my case - I specced fan timers to mitigate pressure issues - but the more pressing concern is adequate dilution air since we are about 2.0 ACH. We are giving each homeowner an Aranet-4 Co2 sensor to help them figure out how high to run the Lunos system. Looking forward to sharing if the system can keep up with the occupants.

[@HomePerformance]

Please fo share as people move in Connor- yes, you’re the one who made me pull the trigger on finally making this vid.

[@markn2904]

Interesting, a real buyer beware and informed situation.

[@Alex4n3r]

3:10 Yeah, that's really informative when the heat exchanger (described as 'regenerative core' at 4:00) is named a filter.

[@norcal_inspector]

This is a good video and I’d be interested to see a smoke test done considering how close the inlet and outlet is.

[@youngrq87]

I appreciate this video and validates some of my suspicions about the efficacy of these units. What is a better option for retrofitting an ERV? I have a new builder-grade home that is very tight and the air quality in the kitchen literally stinks. I considered a spot ERV like this because the only way I can install a ducted ERV is by running insulted lines through my unconditioned attic (I've heard this is a no-no).

[@MarkRose1337]

I gave Alex a follow. I'll watch his video shortly.

[@NicoChiarito]

Thanks for the overview! Those switching Lunos fans seem like junk for the price! On the Ephoca systems, a couple of comments: #1: For the short cycling intake vs. exhaust, intuitively I would agree that this could be an issue. However it seems like this is just your word vs theirs. Or did you smoke test it to see if it short cycles? #2: Just because it is an all-in-one solution does not mean it is inherently bad. It really depends on the application. For a tiny home or ADU, these are pretty great! On a project I am working on we are only required 30cfm of ventilation air. By using the unit for ventilation, we get rid of the need for additional exterior louver, 15-20ft of GSM duct, soffiting and supply register. Time and materials for this completely justifies the additional cost of the internal ERV. It is for sure limited to small homes or ADUs because it can only achieve 40cfm.

[@mikevanwinklemrv963]

Thanks, again Corbett for great content! I am a GC and High School Construction Tech teacher. We are building our first tiny house on wheels and I have been following you guys from when you built the Tiny Lab. Would you still recommend using the Panasonic unit installed like you guys did? We are building a 16' with sleeping loft. I would love your input because we are planning to use this as a building science teaching platform for our community. Thx.

[@HomePerformance]

Hey, thanks for the high five, Mike! Keep up the great work- and to that end, please know we did not end up using this panasocic in our build. See here: kzbin.info/www/bejne/jqqXgKmgeslmf6c

[@josephmerritt1411]

Thank you for the explanation and video. Looking at the spec sheet values and relating them to real-world advantages and disadvantages is great. Is it possible that the all-in-one products are targeted at condo and apartment applications where there isn't an option for ducting?

[@HomePerformance]

Possible, but they don't say so in the marketing. Also, windows work well in multifamily buildings since stack effect is almost always able to drive air somewhere.

[@lukemorton5196]

I agree with your sentiment. there are applications where the lumos might be handy-- especially MF. the few that I've worked on have no room (architecturally) for ductwork. the price point can also be attractive relative to ducted systems, in spite of observations in the video.

[@eymimi]

Thank you!!! I live in an old house and I was trying to get better air quality and run into this products I was like I need it! But I had the same question how I am sure they don’t feeds in the stale air if ducts are next to each other. What are the options for a retrofit house

[@somedude5353]

Will they work to remove window condensation in winter? That’s all I care about

[@whatever_12]

Many people can't use ductless system due to old brick building, concrete block building without attic space (specialty in warmer climate like south america, india and africa) house usually have a split system there for cooling.. would greatly appreciate your recommendation for places like this? Any particular system & brand you would choose overalls.

[@curiousmind1991]

I agree they are not so good value for the money compared to the ducted ones. They are convenient for small retrofit projects though , a lot of European apartments were built without ducting in mind, my own included. I have installed a pair of those in my 2 room flat and they definitely work, admittedly not even close to a ducted system.

[@granworks]

I'm installing a pair of Lunos e2-60 HRVs in the small house I'm building. I was leery of a ducted system since I have an unconditioned attic and having a ducted ERV up there would be utterly pointless in the summer due to the extreme attic temperatures. A through-the-wall system has at least a fighting chance (I hope). Regarding creating an unbalanced system -- I emailed Lunos support on that topic with regards to using them as makeup air for a range hood. The claim is that the Lunos detects when the airflow is counter to the fan direction and will shut off the fan in those cases. Thus, it is literally just two (filtered) holes in the wall at that point and should be able to pull as much air as necessary. We'll see.

[@HomePerformance]

Hope it works out for you, Granworks, sincerely, and I do hear you about the unconditioned attic- not a good place for equipment or ducts. But beware of using these small ducts as make up air- if they're only 4" of net free area, that's like 12 sq in. Normal passive make up air in an average home of serious airtightness is 10" round (78 sq in) or more. House has to suck harder to get more air through.

[@wilyc0y0te]

I’m renovating and extending my home in the U.K. and want to install a system to change the air in the house, but due to ceilings height, cannot fit a ducted system. What are my options if not the decentralised units?

[@ike7933]

Hi Corbett, I have a situation where someone built two small offices ( without a permit🙈) inside a dusty warehouse at a lumber yard . The contractor installed a mini split for each office. The problem is the girls who work in there can’t breath well….Can one of those “single hole” through the wall systems be used?…..I am thinking to install a extension duct , up through the roof of the warehouse for the intake and exhaust air….it might run 8-10 feet, and I can use some mastic to seal around the connection. (Each space is 200 square feet) What do you think? Is there a better solution? I am just trying to keep the girls in the office form getting sick form the lack of ventilation… etc, they are dealing with stale warehouse air,and musty dustiness….(I dont want to waste mony on something that wont work) The other alternative is a stand- alone air purifier perhaps… Please help, thanks in advance

[@ralphlinville6646]

Thanks for the video I’m buying a 1300 sq ft, 2 level home in the Yucatán, Mexico. I want to 1.). be able to ‘turn over’ the air in the house so I don’t have to keep windows, etc, open. And, 2) demumidify the air since this is the tropics. The house will also have mini splits for cooling and 3.) I would want to filter the incoming air for allergens/pollens Can you give me an idea at what I might want to look at? Many thanks 😎. 🇲🇽

[@bellabutler48]

Wow from England! I was looking at the Lunos E2 and found your video really interesting. You see we live in a granite longhouse in the middle of a damp National Park called Dartmoor. We are in the process of insulating the house and have an airsource heat pump which works great in the part of the house that is insulated. However even before the insulation we had a humidity, and therefore a mould, issue and I'm concerned that with sealing us in, the problem will get worse. We are not going for passive house standards but need to reduce the humidity without reducing temperature (due to the lower temperature radiators with the heat pump) - which is why we were looking at Lunos. This is a retro fit to a 700 year old house; so there's no way we can use ducting. But if these spot MVHR units have issues is there anything you would recommend as we don't want cold air blowing in but we need to remove humidity. OR would you say for our situation these could be OK. Please can you help - Steve

[@HomePerformance]

Thx Steve, and understand these may help dry your home in cold months (not guaranteed), while they will certainly spike the humidity in warmer months.

[@bellabutler48]

@@HomePerformance thanks for coming back to me !!

[@catharinamoritz7454]

Thanks for your video. I am currently building a tiny house with 300 sqft / 2 people living in it in the Northwest / Idaho. What ERV system would you recommend installing? Thank you

[@NurseAcrobat]

What do you think of the optional fresh air intake for Santa Fe Ultra dehumidifiers? They lack the energy saving feature of ERVs but if already needing a dehumidifier they can dehumidify fresh air that is brought in through a merv 13 filter, and in the winter can run on fan only mode to keep bringing in fresh filtered air. Of course they cost more than a broan or panasonic ERV so wouldn't make sense if not already needing a dehumidifier, and they could also pair well together, or pair a Santa Fe with a DIY HRV.

[@HomePerformance]

It’s a great solution, keep up the smart stuff. I’ve got a few vids about it- search Santa Fe on our channel if you like.

[@caustinolino3687]

How do these things deal with condensation? They don't seem tilted to let gravity drain out the water. They look installed perfectly perpendicular to the wall.

[@eliinthewolverinestate6729]

I thought spot erv were for a bathroom or a kitchen. And you get a big duct type erv for whole house. I am planning on a hrv too. I need a "vent to daylight" because of masonry floor area. I plan on having a south wall planter. So plan on hanging it above the planter.

[@ericscott3997]

Great Video Corbett, I was interested on what your take was going to be on these Lunos systems. I know a Passive home designer that likes these and has a set in his Passive Home garage and has had issues with them. But then Again, I think he's a bit to indoctrinated with PH standards because his only ventilation is a Zehnder system and has nothing but a recirculating hood vent over his stove.

[@HomePerformance]

Thanks Eric, I think you have your finger on the pulse of things pretty good

[@andreycham4797]

You can find cheaper option I bought Eco flo erv for $ 450 a piece

[@AL-tv7wo]

Hi Corbett, thanks for the vids as always!. You said at about 2m20s regarding Zehnder that you "don't recommend for other reasons". Are you able to elaborate on the reason(s), other than price? It would be a great help to those of us looking to buy a Zehnder. I'm happy to be steered in another direction. Cheers.

[@matthewbono3273]

This is what I came to the comments for, or at least another video to watch where different units are compared.

[@JeffMackler]

I’m wondering about this too. I’m about to buy a Zehnder and would love to be convinced otherwise. I want the best at any price.

[@mattffleague6041]

@@JeffMacklerdid you buy the zhender? Did he ever elaborate on this topic?

[@JeffMackler]

Yes, we got it, but it's not in yet. I actually got on a call with Corbett and asked him about it. He thinks it's an amazing system, but he thinks it shouldn't cost so much. Fundamentally, he thinks every home should have one, and that's only going to happen if the price comes down. He didn't hesitate to say is' the best. We are cutting some corners in other places so that we can get a Zhender because we had mold and air issues in a former house, and it's just where we want to put our money. @@mattffleague6041

[@superspeeder]

The Lunos can recover moisture in cold weather when the incoming air is below the dewpoint of the outgoing air. Moisture in the outgoing air condenses on the core as it warms, the evaporates into the dry incoming air as it cools. I don’t believe it’s as efficient as an ERV, but it’s much better than nothing (a la HRV). Regarding balancing, if you put a pair in the same air space you don’t have to worry about pressure zones messing with balanced airflow, but this gets spendy real fast depending on how many zones you need ventilated. I agree with all the negatives, especially price. If designing a house from scratch there’s no excuse to use these over a ducted system.

[@HomePerformance]

Interesting point about the condensation recovery, @superspeeder

[@superspeeder]

@@HomePerformance the opposite would also be true in hot humid weather in a house that’s air conditioned, but I suspect the effect would be pretty minimal. If Lunos is not advertising it, that probably says all we need to know.

[@HomePerformance]

Solid thinking

[@KPHVAC]

Corbet - If you were shopping for a home that wasn't brand new or custom, what age range would you suggest? It sure seems to me that a house built in 2010 is world's better than one build in the 90's. From what I've seen anything before the 70's that hasn't been remodeled needs a huge amount of work. I'm looking to buy a house soon. I'll be inspecting everything myself plus hiring a good inspector and doing some testing!

[@KPHVAC]

@@methos424 All are good points. It's hard to judge just based on a homes age. As a residential HVAC system designer I hate old houses unless they have been remodeled properly. Almost everything I see from the 70's and 80's needs so much work! New insulation, new ductwork, new electrical, new windows, etc. From a comfort standpoint I think 1990's or newer is better!

[@HomePerformance]

Great convo guys, KP you’re going to love the next vid. Special treat for your PTSD.

[@tweake7175]

There is a brand here that sells a mini erv similar to those. However by the time you fit one for every room the cost is horrendous.

[@oaklejant]

Brand name?

[@tweake7175]

​@oaklejant Google is your friend. It depends on where you live.

[@MrLeeCox]

Interesting video. I'm about to build a studio in my garage, hopefully sound proof as I'm going for double stud, room in a room. The room will only be 6m x 3m x 2.5, but will house my vinyl collection etc. My concern is heat and humidity of the summer months here in Brisbane. Would these All-In-One Ventilation be ok the a small room, the single is called mono here? I was planning on connecting my house ducted AC, adding an inflow for fresh air and then EVC for heat/humidty control, but might be overkill? \

[@leonscott543]

Ductless would be great for a small cabin in the woods that is extremely airtight

[@Casperankinen]

6:47 - Alex canned his DIY HRV because it made the air quality in his house worse and ended up buying an ERV & Dehumidifier. So the DIY option is really limited to non-humid climates. What I really wish anyone would explain is what exact materials and parts are different between HRVs and ERVs (not the outcome)

[@HomePerformance]

All same parts, but the core is made from composite or paper in ERV, and plastic or metal in HRV.

[@Casperankinen]

Thanks, I had a hunch that’s it (apart from some code on a control system running similar sensors) and it wouldn’t surprise me if the cores, whilst proprietary, are made by other companies because the chemical/material science is very different to usual HVAC machinery to warrant them having this inhouse. This is more like 3M, DuPont turf than established air-conditioning companies. So really it’s about who can come up with the cheapest cores that meet the performance requirements and then it’ll turn into the printer ink cartridge/vacuum cleaner bag market with the interplay between higher capital cost vs. maintenance costs.

[@drewhenriques1359]

Sorry I might have missed this but what was your conclusion on the best way to filter and exchange air and humidity without having a system with ductwork?

[@HomePerformance]

Well, ‘best’ is very relative to your family type, health status, goals, home type and location, and budget- we’ve discussed several options in past episodes but I’ll add this to the list of planned vids

[@drewhenriques1359]

We have a 2 story holiday home in Exeter England. My wife is very sensitive. She wants the ERV but is concerned with having ducts bc she wants to be able to clean the tubes every so often. Is there a creative solution to how it is installed so that the tubes can be cleaned?

[@johnwhite2576]

Re zhender-aside from the obvious-price- and inability to imbalance -ie establish positive pressure, and as you have demonstrated, non negative pressures in the house as it’s impossible to generate really high pressures in American homes- any other issue you ha with zhender? Thanks

[@HomePerformance]

They do tend to oversize their ventilation systems for homes- every design I've ever seen is way oversized, might be because they have a gap between ~110 cfm system and ~250 cfm system.

[@davidhoover2446]

I think the Build Equinox CERV2 looks awesome. I’d buy it if I had $6,700.

[@andreycham4797]

You could buy stuff like that from China hrv with heat pump built in for $1200 plus tax and shipping before covid

[@alexanderjamieson7971]

Do any ERV's filter up to HEPA level?

[@ZeoCyberG]

Yes, larger units can have air filtration.

[@withsandylam]

What if ducting is not an option? What options do you recommend?

[@HomePerformance]

Every product has its ideal use case, I’m not saying these don’t do what they’re designed to. But they do not offer the dynamics control of a ducted system, and you should consider how airtight your home is (blower door test) anf where your air is currently going to/coming from. Watch this: kzbin.info/www/bejne/fICtaZmpdruIl6s

[@kevinharvey6591]

Thank you. Much appreciated. we are renovating an old farmhouse up in Quebec. I have no duct work. I’m doing a combination of baseboards. And looking into ductless heat pumps. I put a complete envelope around the house, firstly, with R4 sheeting taped. Then R 6 rigid foam insulation with built-in air barrier. That tape as well and then regular vinyl siding over that. I’m hoping the house is fairly airtight, all the windows have been changed with triple pain windows. But I’m looking for some kind of solution for ventilating and creating a balanced cost-effective way of doing it. The house has three floors. With the staircase in the middle. The inside dimensions are 32‘ x 22‘. Quite small. I will be adding an extension on the main level for a bedroom. With no basement. or upstairs. Open to suggestions. Right now the house is still mostly gutted on the inside. Just starting to run wiring and insulation and plumbing etc.. Thanks again, I really appreciate your videos Kevin

[@JC-jv5xw]

I fail to see how a pair of inlet/outlet fans alternately switching provide any sort of heat recovery as there is no exchanger?

[@paddyeason9677]

There is a ceramic honeycomb heat exchanger element, he just didn't spot it when pointing at the elements of the unit in the diagram. Which, I have to say, made me wonder exactly how well he understood the system.

[@DavGreg]

Regarding Tiny homes and IAQ, is the issue more outgassing from the building materials or from the humans and activities (cooking, etc)? I remembered you used plywood that did not contain formaldehyde for the indoor walls on the Tiny Lab.

[@HomePerformance]

Technically, all wood offgasses formadehyde, as do human beings. Choose materials wisely, but we live in a eorld unavoidably full of chemicals. We just don’t want to have any of that build up, which is way more likely in a tiny space.

[@ZeoCyberG]

​@@HomePerformance Yes, smaller space does mean it's easier to reach higher concentrations in the air, but that may be too much of a blanket statement as it ignores how larger spaces can simply have more materials that are off-gassing, which could make a larger space just as dangerous. Especially, if the builder isn't as careful in material choices and methods used, which is more likely to be the case in most regular built houses. While ignoring that people living tiny tend to spend more time outdoors, versus the average person spending about 50% of their life in their home. So exposure may not work out the same for everyone despite the size of their home.

[@Obtuse94]

So I am understanding correctly, there aren't really any recommended solutions for retrofitting in a home without ducts? ERV/HRV or otherwise?

[@KPHVAC]

It would be a whole lot better to have a ducted HRV or ERV. Do you have a crawlspace or attic? I refuse to buy a home without a crawlspace or attic for every floor. They makes life so much easier for future changes with electrical, plumbing, HVAC, etc. I'm also totally happy with the little condo I rent that has no HRV or ERV. I leave windows cracked open year round. If you live in a small town with good air quality a window can totally work for you. It's not a good solution if you have high humidity, allergies, or bad air quality.

[@HomePerformance]

You *can* make things work, but you'd need to do surgery no matter what, there are rarely any easy solutions for retrofits. And duct systems just make everything work more efficiently.

[@superspeeder]

If you have a forced air ducted furnace or AC you can plumb the ERV in and use the existing ductwork. Not as ideal as dedicated ductwork for the ventilation system, but still an ok solution.

[@MarkRose1337]

Are you talking about the Hyper Heat H2i? It goes down to -13°F. I wish they had a version for cold climates that worked down to -25°F or colder.

[@HomePerformance]

It does go down to -25, just less efficient.

[@MarkRose1337]

@@HomePerformance That's very interesting. For my purposes as long as it doesn't stop working, it's good enough. I wouldn't mind if my interior temperature dropped to say 60°F on the coldest of days. Do you know what temperature they actually stop functioning at? I know many systems have a cutoff temperature for protection.

[@andreycham4797]

Look for Gree models Ultra for cold climate they claim the latest model with three chamber compressor could work down -31 F with 80 percent output from nominal capacity

[@pasternakel]

You just missed discussing the ceramic element on the lumos… did you had this pruduct in your hand? No otherwise you would talk about it

[@HomePerformance]

That’s the recovery core, which is why it’s an HRV and not just fans, no?

[@wgamborski]

Corbin, would like to discuss when convenient. I am a Building Official, Licensed Energy Advisor and Certified Passive House Consultant with some experience and testing background on these. Would like to to talk and geek out.

[@HomePerformance]

Hey Wayne- thanks very much, please do post any comments and experience you have with these here in the comments. It's 10pm and I'm still up doing heat load calcs for clients before I get woken up by 3 kids before daybreak. Not much time for geeking out in spare time lately!

[@raptormatt21]

Have you been involved in any projects using the CERV2 from BuildEquinox?

[@elbertakibler]

I'm really curious about CERV2 also!

[@HomePerformance]

Alright, guys, I'll find some time to dig in. Video is on the list.

[@superspeeder]

As far as I can tell the CERV is very similar to the second system Corbett looked into here. Basically it uses a heat pump to recover heat from exhaust air instead of a cross or counter-flow heat exchanger. The big deficiency I see in these units is they operate on sensible-only heat, like an HRV. No moisture recovery like an ERV.

[@superspeeder]

@@doughorgan1877 Excellent point, Doug. I’m in a cold climate and tend to think as such, but for those in hotter and more humid climates a CERV type product certainly makes more sense for the reason you mentioned, as well as the reduced sensible heat loads and higher outdoor winter temperatures. Where I’m at (on the cold edge of Zone 6), winter dryness is a major factor and people who have average code-built homes suffer from extremely dry indoor air who have HRVs.

[@andreycham4797]

Cerv is way overpriced Canadians make something similar

[@evanpierce564]

Would have liked to see you do more research about the Lunos before claiming it doesn’t recover humidity. More research would have enlightened you to the fact that the e2-60 adjusts to pressure imbalance so theoretically the bathroom exhaust add-on would work. I installed these in my house because we couldn’t run ducting and they are working very well. Not an ERV but better than nothing. Again, maybe a bit more research since people are coming to you for expert advice. You even described the lunos components wrong. :(

[@HomePerformance]

Hi Evan, glad to hear they're working for your needs. I hear you, but context is everything-- these are marketed as HRV, not ERV, technology. Also, many defenders of these systems in these comments keep saying they're 'better than nothing', and 'good for retrofits', but these are clearly being marketed as a new, passive house home solution alongside many other top-tier airsealing and insulation and window products that are far from 'better than nothing' or 'good for retrofits'. My clients are selecting these without being informed about the pressure and balance side effects, and it's money wasted in those cases- hence this video.

[@oisin3928]

How are they not HRV? They literally have a heat exchange in the middle which you didn't point out when detailing the components.

[@trickstothetrades1801]

When we look back 50 years or so and look at how construction and HVAC was done we laugh. It would be interesting to be able to know what our future selves will think about our current methods of construction and HVAC. Hopefully that we got it right but more than likely they will laugh and say I can’t believe they thought this or that was a good idea

[@HomePerformance]

I know I’ll be looking back at myself, shaking my head.

[@generalbystander1631]

Why is Zehnder out of favor with you?

[@HomePerformance]

I’m in favor of all ventilation, when used in the right application as part of a system. You can see Zehnder in my ‘bath exhaust with ERV’ vid and in the most recent 2024 Ventilation Showdown video.

[@mennomateo]

Look at the power requirements I believe they're 220V as it is European

[@st3ppenwolf]

Why would you want to install an ERV/HRV in the bathroom??????

[@HomePerformance]

?!?!???!?!???

[@st3ppenwolf]

@@HomePerformance wouldn't an exhaust fan be more than enough?

[@HomePerformance]

In very airtight homes you cannot use one-way exhaust fand without major pressure problems.

[@st3ppenwolf]

@@HomePerformance That's not the point I am trying to make, why would you want to circulate a bathroom's humid/stale air inside the house by using a ERV? air in bathrooms should go one way only and that's outside through an exhaust.

[@HomePerformance]

That’s a very common misunderstanding- ERVs do not circulate anything- they take air from the house and dump it outside, bring a similar or equal amount inside, and brush the two together in a recovery core that transmits no odors.

[@simplyaaron]

As bad as these solutions are as far as filling the actual intended function of an HRV/ERV, I don’t think that the price is really a criticism. Sure, a typical ducted HRV/ERV is only $1200, but then you need another $1200 in ducting and registers. Outside of the raw material cost there is also the labor to plumb it, then to balance it. The true cost of your typical Broan system starts at $4k. I don’t really know who these systems are marketed for, but I could see that the main selling point is a low labor/cost way to meet code for mechanical ventilation with no regard to actual performance.

[@HomePerformance]

Sure, good points Aaron

[@MarkRose1337]

You would think they'd have a bath fan that integrated with their two piece HRV to provide balanced ventilation.

[@andreycham4797]

Yep he missed the point about that lunos with two small fans

[@evanpierce564]

The e260 adjust to pressure imbalances. So kitchen fans or bath fans drawing out air, and creating and imbalance isn’t much of a problem. Not as good as an erv but the next best thing over nothing at all.

[@HomePerformance]

The net free area on these is very low- consider that if they only pull ~30 cfm with the fan running, if you turn it into a passive hole it’s probably less air coming through, no?

[@MarkRose1337]

@@HomePerformance Makes sense!

[@amiller8822]

So then what WOULD you recommend, for Tiny homes? Which don’t have room for ductwork. Right? What are some solutions? I need to decide and order, this week! 🫣 I feel kinda like this leaves us hanging. And, where’s that video you’d done on why you’d recommend ERVs? (Why wouldn’t you want an HRV, to preserve heat? Especially in a cold climate. I mean, you may as well just open a window w/o having the heat recovery aspect! Right? 🫠) And, why can’t there be a unit that does BOTH? Deal with heat *and* humidity! 🤷🏻‍♀️

[@tweake7175]

Erv does both.