I would love to see more videos or a live stream with experts discussing HVAC. We are remodeling our old house and updating everything. Using closed cell foam and AeroBarrier. Hoping to get below .8 ACH/50. All our local HVAC companies that have looked at our job have had no experience with HRVs. They haven't been able to answer how tight/when you need HRV. How to vent bathroom/range if you have HRV.
For anybody that wants my first hand experience here it is. Built a 2ach50 barndominim super insulated double stud frame conditioned crawlspace the works. I've been cooling and dehumidifying it while I built it with the hrv off. Electric bill in summer 30 bucks. (very minimal attic insulation still) Moved in turned on the hrv. It takes air out of the bathrooms and brings air into the HVAC return. Humidity went through the roof. The dehumidifier ran all day and only got the house down to 60 percent. Electric bill was on track to be 250$. Turned off the hrv and the humidity dropped 10 points in 3 hour. In my opinion it's a waste. Ymmv
Ultimately Zehnder needs to bring the unit from Europe that integrates a dehumidifier with the system to the US: the ComfoCool Q, not just the ComfoAir Q.
As a person that has a Zehnder unit in the US, I couldn't agree more. We could not achieve less than 75% humidity in our home during the warm months. We have to have a separate unit to do the job now. Built in would be amazing.
As much as we all would like an dehumidifier on an ERV in many climates it does not work. When we look a the volume of air brought in and the amount of water that can be removed from the volume of ventilation air in humid climate. It would be less than the water that gets in by as air leakage, diffusion, people exhaling, perspiring, showers, cooking, plants, pets, capillary from the ground, washing dishes, did I miss anything? So even if the dehumidifier could remove all the water from incoming ventilation air it would not be enough in many cases.
These systems are crazy to me. I grew up with hot water baseboard heat in Michigan's upper peninsula and gas forced air in Wisconsin. I love the idea of each room being dialed in and not just guessing
What is a bit odd is that the system when triggered for the bathroom seems like it will send the WHOLE unit into high speed mode, and not just the single room that it is needed as the whole system is balanced at a room level by what is essentially manual dampers. There could be a potential for efficiency improvements.
Putting the unit into boost mode is just going to proportionally increase the CFMs at all registers, which includes the bathrooms. I understand what you're saying about how only putting bathrooms into boost mode would increase overall efficiency, but to my knowledge, there is no fresh air system on the market that can do that.
@@anDWandy True. I do believe there is usually a localized return path to the main unit in the same space, which would keep that pressure balance as long as the return stays in step with the source. I could be wrong though.
It would be cool if for the cooktop air system, turning on the exhaust fume hood could send a low voltage signal to the ERV, which would trigger the ERV to increase supply air CFMs by how ever CFMs the cooktop exhaust hood is removing. Yes, the ERV would not technically be balanced during this moment, but the whole house would still be balanced technically. I would imagine one of the reasons for not doing this is that the cooktop exhaust hood removes too many CFMs that the ERV couldn't make up. Still a cool idea though. Great video!
Originally my Zehnder rep told me it would but after much discussion with the engineers they said it would not. I don't see how it couldn't detect the negative pressure at least up to its capacity and shut down the other exhaust temporarily to compensate, but it doesn't work that way. In general it actually isn't as smart as you might think. For example, if you use a boost switch in a room it doesn't just boost that room, it boosts the whole house for that time period.
No, I don't think it is. It would be nice if they would make the information on how to design the system public and the components purchasable by consumers. That's probably the only way this system would end up in my house, but it looks awesome!
Hey Matt, great series. If you were to eventually sell this home what kind of documentation of all the systems (e.g. HVAC, etc) would you put together for the new owners? Curious because I'm sure most home owners wouldn't know where to start if something stops working.
I got the idea from Matt's ERV videos to do something similar when I built a large house and had the HVAC guys install a 300 cfm ERV which pulled air from bathrooms and laundry rooms and put fresh air in bedrooms. In addition to the whole system percent timer, they created a circuit board with zone dampers in the duct work which defaulted to fully open that worked with analog bathroom exhaust timers so that when a bath room timer was activated it would partially close down dampers going to other bathrooms (two laundry exhausts always remained fully open) and therefore pull harder from the offending bathroom (or bathrooms if more than one was running a timer concurrently) until the timer ended. The 'bath exhaust timers' would also activate the ERV if it wasn't already running based on the percent timer. It was silent and worked EXTREMELY well to get rid of smell. That being said, I missed the noise created by the exhaust fan so it made using the bathroom a little less private.
@@aayotechnology No, the ERV removed house air from bathrooms and the laundry rooms and put that air outside while bringing in fresh air and putting it in bedrooms and near large return air intakes to get distributed through out the house.
System looks great! The only questions that I have is what happens if you have a hurricane, tornado or snow storm and you loose power in your area for days or a week or two? Will you have to open your doors or windows to let the air circulate out the CO2 that’s trapped in your home?
@@rory644 for sure, but how big does that generator need to be? What else does it run? And do you have enough fuel to operate everything for a prolonged period of time?
Good grief, watch his other videos! He has at least one about the generator he installed, and I think he helped neighbors when the power was out for several days last winter. If you think he's gone to all this trouble without considering emergency situations, well, think again.
@@CitEnthusiast my point is simply that there a lot folks out there that aren’t taking that into account. Just looking out for others to help make sure they think it through as well.
Mat, unless I've missed it, could you do a show on your induction stove top. Maybe after your wife has used it for several months. I have used counter top induction for years. I've heard good things about stove top units. I would appreciate a deep dive on induction. Also what type of oven you are using. Thanks
The only type of dryers allowed to be sold in Europe are the condenser types. Like you have installed. As an American I find them inferior to our gas powered dryers. Comparable gas dryers are not very energy efficient but the speed and results are great. Have you compared the results of the two?
We have a Miele condensing dryer in the garage. It works great, built like a brick s********...German quality I guess. Decided to go with one for our remodeled house didn't have a vent installed in the garage. The Miele also uses a basic 15 amp household 120V outlet, freeing up the NEMA 14-50 dryer outlet for our EV charging. Most likely saving cash on both ends over retrofitting for a vented dryer plus second 240V EV outlet, plus the energy savings on drying (we're seeing 600-800 watts on the dryer). Downsides: - The model we went with is small, great for a small family household, but will become apparent with more laundry. - it's a closed loop system, with 3 filters. Two of the lint filters require frequent cleanings, they are sandwiched together for ease, but for proper drying they should be cleaned between loads or cycles. We keep the garage vacuum near for easy cleaning. The third filter is essentially a sponge, and should be cleaned or washed infrequently.
@@macthemec Warm and fluffy. About the same. The real question is do we stay cheap and burn stuff and vent it to the atmosphere (coal power plants, gas dryer and water heater), or do we have expensive renewable power and very complicated systems for efficiency?
Hi Matt, I'm a builder from Australia, Melbourne and we love your work. Given your extensive knowledge in this subject I'm wondering how to ventilate timber frames naturally with ICF type walls? We use Dincel or pvc concrete filled walls for basement constructions. Would you recommend steel frames? Or is mechanical ventilation the only option? General method is brick veneer facade on timer frames, which has obvious limitations with respect to insulation but evenly spaced weepholes or vents ensures no moisture build up against timber frames.
Hi Matt, I LOVED this video. Just one question related to your "Balanced & Distributed" system... Are you somewhat over ventilating your home? I know ASHRE doesn't give credit for a Balanced & Distributed system... but Doc Joe Lsebrick's BSC-1 does... and on my house it ended up being a lower overall CFM requirement for our home as compared to the ASHRE Standard. Cheers, Eric
It would be interesting to see a chart that ads up all the additional cost for all this fancy tech needed for a super tight house vs just building the house normally and losing a little heat
This is not about energy at all. Matt touches on this in the beginning of the video. Bring in fresh air where and when you want it. Right now, I live in a place where the bedroom gets pretty warm over the course of the day in the summer, and I can't tell you how many times I open the window at night and but the temp inside doesn't budge. It can be 20 degrees cooler outside, I'm not feeling any of that if there is no breeze AND it's not blowing in the right direction. Sometimes the stars have to align too... This is about designing for control and optimal health and in the process not throwing away all of your conditioned air. @@justinballard7242
this is great, love the concept, and being efficient and having control, but having to always change a bunch of filters and clean things out, it's just one more piece of maintenance to a house. plus if you loose power, or there is a surge, is the unit protected? does it remember all it's settings? With my current 'drafty' budget house, there's only 1 filter I have to change, and I don't have to get on a ladder to do it.
The filters for intakes is an extra just to keep your ducts clean which should be in every home (bathrooms, return air etc) It would be like having filters in intakes for a regular system.
This maintenance will be annoying. Seems ok right now, since this is all new. But give it a few months and you will find yourself wishing you hadn't. It's much much easier to place the filters at floor level where you can reach them.
The placement of the in and out units allows heavier particles to settle to the floor, if it's as balanced as they're saying. I want to know how this compares with ground source heat pumps in terms of payoff, power requirements and efficiency. This is obviously a simpler setup, although tuning is likely the key after the tight envelope. Geothermal payoff is about seven years. The Federal tax incentive, if it continues, pretty much pays for the drilling and tubes. Provided you aren't above geologic voids it would finance the grouting of those tubes for continuous contact with the native formations. A customer can see a bunch of money go down a hole in karst, or dissolution environments. Good contact is key for heat transfer. The story behind the mini split. Is it for the basement? I may have to find the installation video.
@@richavic4520 there really is no roi for this though... It is simply fresh air supply because it's a tight house. I'm not sure how you could measure how much it saves when it isn't producing heating or cooling.
Matt, that looks like a well-engineered system but I think it's overkill. The central air handler can mix & distribute fresh air right along with the heat/air and thus avoid all that extra expense for separate ducts. A variable air volume system with direct digital control can deliver air continuously in just the right amounts to any room that needs it. Co2 sensors and dehumidify/humidify control give precise whole house control. And the maintenance is all at the central location. A few Phoenix valves can do the job. ua-cam.com/video/003m3QD7UVs/v-deo.html
Excellent point. We have used this system in a few of our builds because the client really wanted it. However, we generally go with exactly what you just recommended. Matt is doing a fine job on his build at any rate. 👍
@@dandan1364 Ducted? The whole idea behind mini-splits is 1 unit for 1 zone, multiple units for multiple zones. A variable speed central system can have zone dampers to control multiple zones.
@@ToIsleOfView That was 1st Gen mini-splits. Modern units can have multiple zones with 2+ compressors in the outdoor housing. Some, like Mitsubishi, also have manifolds to direct the output to multiple locations. They're moving heat around the home to where it's needed instead of just bringing heat in or sending it out like the early tech did. Obviously, they can still do that--send heat out or bring it in--as a part of the process. At Matt's home, for example, he used mini-splits for heating and cooling, but a Zehnder ERV system for ventilation (fresh air, enthalpy management, exhaust). There is no 'central air handler' other than the Zehnder. No sheet metal ducting, etc.
Matt, did you install a barometric relief damper into your kitchen hood exhaust line? Even with the fan off, it will have a natural flow of air out otherwise...
@@chuckley54494 Yes, there is a damper on the make up air, so air wont come in when not in use. I am wondering about the exhaust line? The pressure from the ERV will force air out of the house if he does not have some sort of damper..
I'd love to see a CO₂ (carbon dioxide) sensors included in the system with automatic increase in fan speed for the CO₂ increases like during a party on a cold night.
The system supports up to four CO2 sensors and can boost the fan speed if increased levels of CO2 are detected. It was mentioned in the previous video about the Zehnder install at his house (prior to this commissioning one).
Not commissioning, this is start up. After startup and air balancing (TAB) is done. After all there start Commissioning process: 1) Cx BOD (Basis of design) document review that BOD meets OPR (owners project requirements). 2) Cx design review 3) Cx submittal reviews 4) Cx review if receipt of until in site, how its stared, boxes in good condition, all parts and options there. 5) Cx installation inspection. 6) Cx pre energization inspection. 7) Cx pre functional inspection 8) Cx Functional commissioning after unit start up and TAB air balance reports completed and reviewed. Test all unit functions and performance. 9) IST interested System test. Test all systems with everything's ng in home completed to verify all systems function together 10) Cx Seasonal commissioning, winter fall, summer. 11) 10 month warntee review if all commissioned system, retesting all, all definitely ciencues reported so full fixed before GC 1 year warntee expires. 12) CX periodic recommisioning check all functions, review energy use and system changes.
I like how they have an expert setting up the system but it would have been cost effective to tie the ERV into the air handler and have that continuous running and balance one system. for bathrooms use a timer and a posh grill so the ERV favors pulling air from specific bathrooms. The HRV/ERV debate, we generally use a ERV in a radiant heated house because they have have lower humidity levels and a HRV would make the air too dry here where its humid.
Running ecm 80 cfm 24/7 piped from outside through a three filter staged air box directly into furnace plenum intake then filered twice merv 12, ti02 filter then 4 uv lights above and surrounding a coil and one in center a coil, timed. Three class 2 medical filters running separately at 80 cfm x2 and one at 100 cfm. Not much more i can do. Electric bill 150 mo. All electric. All led lights. Need to install heat pump water heater sitting in box in garage. Maybe solar air heating to heat partially conditioned crawl space, no floor insulation. Bare cinder block surround skirting but foam sealed to house rim joist, platic liner on ground. Bubble foil wrap on all venting. No flexible venting or garbage yellow or pink moldy stuff. Subfloors painted with kills and hytech ceramic additive [r7 est.]. Need to seal and insulate cinderblock skirting and one more wrap of double bubble on ducts, paint underside of subflooring with kilz and hytech lay down foil infrared blanket on ground the ill b done. All protrusions in floors, walls and exterior outlets foamed. Hvac closet walls foamed three pound pourable to prevent condensation into walls and seal cavity. Hvac pan double insulated, double panned with water sensor, antimicrobial. Drain line pressurized to prevent fouling of drain line, cost gaurd style, and backdraft thru line also skupper check valve. Petot tubes to follow to ballance air flow with filters. Need better butterfly vent assemblies in bathrooms and on micro vent. Need closable chimney cap. Currenly fresh air intake on fireplace foamed shut as i dont use it but can open it if needed. Furnace motor ecm constant run to circulate air it has prefilter and draws some air from water heater room which has its own wall mounted filter next to refridgerator to capture humidity and warm air from ice box motor. Shower or bath cavities vented and water alarmed. Lennox elite heat pump has its outdoor coil elevated off of ground, sided and roofed in its own "doghouse", screened and protected. I have video of it on my channel hvac coil doghouse. All lines wraped with armaflex and where exposed to weather 3m extreme weather hvac metal tape. Thermostat staged 66 to 70 f.
I enjoy the theory of fresh air system. So much off gassing from furniture, appliances, flooring, cleaning chemicals, etc. In our petrochemical world, plastics especially the ERV plastic tubing gassing has its issues. My brother is a chemical engineer. European cars must meet parts per billion off gassing in cars(plastics, etc) vs USA standards parts per million. It is hard to completely get away from air pollution. I live in Hawaii but we all still breathe the same air. Enjoy your videos.
Why not just install a couple 6 inch Merv 15 plus or Merv 16 air filter with an ECM inverter Drive HVAC and combo unit and run it 24/7 with an air exchanger?
@BuildShow... at the 16:30 mark, you have duct tubes all over the floor in the attic. In one of your other videos, you featured a conditioned attic, where the client was an engineer, and he used a CNC machine to punch out 4 inch holes in a sheet of plywood cut approx 2' x 3' so that the plywood could be mounted on the rafters, and the ducts routed through the punched holes to keep it organized and off the floor. Can you help me find the link to the video I'm remembering? Thanks so much!! I want to share it with a client. WAIT... Never mind... I found it!!
Coming in way late for this video, but I am really impressed. Thinking way outside the box, maybe, I was wondering if there is a kill switch, or if there is a need for a kill switch in case of fire to remove that constant fresh "breeze" and reduce/remove any additional fuel to a fire?
for an upgrade, you should go with a Bora downdraft extractor for your stove that simply filters the air and keeps it inside the envelope. creating a penetration for your range exhaust is not wise in a near passive design...
Was going to ask the same thing… why not just run a whole house purifier thru the hvac? I understand it pulls air from the bathroom but seems a lot cheaper, less hosing and less hassle to just run a Santa Fe purifier and dehumidifier.
You have to open windows after a while. My house is insanely tight and uses a far simpler system to bring in fresh air (opens outside vents for 5-10 minutes out of each hour and runs the central air fan to pull the air in an distribute right through the normal vents, standard air returns work to cycle the air inside the house, one external vent opens to let some air out to keep the pressure balanced)... when the power was out here for four days we noticed stale air after the first day and cracked open a couple windows (in -6F weather that's not terrible pleasant).
Matt, I will be curious to hear how you like those Miele washer and dryer sets. My Zehnder system is about 75% installed and just started thinking about what to do for ventless dryer. All roads seems to point to Miele and Bosch for heat pump dryers, but I don't know anyone who has one. Everyone I know who has a condensing dryer hates it, so I'm crossing my fingers that these new heat pump dryers cut the mustard.
One problem is none of the heat pump dryers are as big as traditional US dryers, so forget about trying to dry a comforter. Someone used to make a large heat pump dryer, but it's been discontinued. It will also take a long time to run, as the hot air isn't nearly as hot as gas or electric. If you are OK with more frequent small loads which take longer to run (and the filter cleaning), it is more efficient to operate and doesn't send conditioned air outside.
We've been using a Bosch heat pump dryer for years now and we love it. It does take longer than an electric or gas dryer. Most loads take 80min or so which isn't a big issue for us. Being able to place it anywhere and not worry about venting is great.
I want to know if it is necessary to attach a standalone humidifier to the Zehnder system for more hot & humid regions like West Africa (humidity is consistently over 75%).
Depends. I live in an area with 90%+ humidity in summer but my house is so dry from the AC running all day every day that grapes turn to raisins on the kitchen counter. However, Matt has an older video showcasing an AprilAire in-line dehumidifier so I'm guessing in a lot of cases you would want a dehumidifier. Remember you want to keep your house at 40-60%
@@Eric998765 I plan on building a passive house to keep the expensive conditioned air as long as possible. Considering I will be using the AC consistenetly to maintain the ambiant tempreture I guess a separate humidifier might not be necessary.
@@DanielDuedu With a passive house, much of the air conditioning load is from the electrical use indoors, and a small amount for leakage and door opening. This means a much smaller A/C unit is required, which may not dehumidify enough to meet desired humidity levels, thus requiring a standalone dehumidifier.
@@johnhaller5851 Thanks for the reply but won't a smaller unit take longer to reach the desired temperature as compared to a bigger unit that will reacher it faster and cut the power. This effect is amplified in a passive house because it can sustain a set temperature longer.
@@DanielDuedu Yes, a smaller AC unit will run longer than a larger one. But if even a smaller AC unit isn't needed much to reduce the temperature, the humidity levels will still go up because water vapor is also trapped in a tight house, and respiration and bathing will increase humidity over time. If the temperature is correct, only a dehumidifier can remove that excess humidity. If the outside air when changed to indoor temperature will have a lower relative humidity than the target indoor humidity, then the ERV can be used to lower the humidity.
@@aayotechnology it goes outside. Part of the moisture can be returned to the input stream of the air since this is enthalypy unit and it recovers part of the moisture only if inside air is dry, it is natural process happening on the heat exchanger of the unit.
How is this routed to the first floor rooms? Did you have to build chases into the architectural design to accommodate going from an attic space to a first floor/basement?
Hi Matt, Since you moved in, how has it been using only Zehnder in the bath/shower to evacuate steam? How much CFM will it be with boost switch activated?
Except for the mini split above the stairs [9:43]. Those do have a screen [I wouldn't call it much of a filter] that needs occasiomal cleaning, plus... when the remote pukes on you, physical access is required to try a reset or manual activation. I know zero people that keep scaffolding handy for their homes - just never happens. An architect dreamed this up???
@@flinch622 valid point. It's just for extra cooling when there is a lot of company. I'm pretty sure it's not intended to provide added filtration. I think I might be able to reach it with my little giant ladder.
I like the UV idea - sure fire way to knock back mold spores. It needs an easy access location as lamps need annual replacement. Still need a filter to deal with the bulk of nuisances however.
10:30 seems like you coulda just put one of those zender vents behind the matching faceplates? I assume they didn't fit? Looks like they could have by the looks of it. (You would have to make a manifold or something.)
You are commissioning the system with dirty filters ? Sounds like these readings are going to be biased. For a normal system might not make a difference but since you are being so exact I wanna bet there is an offset somewhere... Very cool system none the less !
Good vid, and whenever specialized gear arrives to a project tha always brings up "why" - reasons can vary greatly.. You know, it's funny: we seem to need to purchase more and more specialized equipment [often electric] as the "eco" mantra is followed, and housing is not immune. There is a subtle difference between that and purely engineering based efficiency solutions - beware of mindless marketing. Foe example: I suffered upon a LEED website last week and observed the business of a rating system is largely politicaly defined [salted with incorporated references to ashrae, EN, etc standards to imbue apparent engineering legitimacy]. As a sidenote, bankers [such as Dimon] have salivated over carbon credit schemes in the past. Why? Because there is nothing to ship or store - zero capital investment for brick and mortar required, and with government fiat status comes...zero liability. Good stewardship of resources is important, but you have to filter through the fog. If you are building for third party "credits" and not results... well, good luck with that.
MKTech This can be done by installing a Zehnder filter box between the manifold and sound attenuator. This will allow balancing the unit with any grill as long as a flow hood can be placed over the grill. I have clients that do this with linear diffusers. They build a split boot where part is for heating and cooling and part for ventilation. And yes the same linier can have a return ventilation and supply H/AC. As long as the velocity for the supply air is high enough it will blow the air into the room and mix before the air goes back to the return,
There are filters on each return duct... 😳Those are definitely going to be forgotten about over time. Matt might not forget to clean them, but if he moves, they're never going to be touched.
Nah, he will give the new owners a call every 6 months and remind them... Or they could program the fancy lights to sound an alarm every time they need changing.
With the Q unit when the static increases past a point due to plugged filters an error will occur. If the app is installed on a phone a notice will sow up on the app icon. As well as an error on the controller will show up.
This sounds suspeciously like another expesive gadget to lose its memory with every power surge or failure. Did I hear, fifty interior filters to remove and wask every 3 or 6 months? Filters that you need to stand on a ladder to access?
Some people just leave it at its medium speed and others choose to turn it to the away mode. Then again some find with proper filtered air they will never open the house again.
@@andrewwahl4503 this is how it is at my place. I have the system for 4 years and no need to open windows anymore. And that is the point, you have fresh air 0-24 while system is recuperating energy that would otherwise be wasted.
Can you show/explain how the return air is handled? I have seen options for wall grill vent, bottom door solutions, door seal solutions, door frame solutions, but I am curious how you solved that in your house.
The Zehnder has supply tubes and return tubes. It’s a balanced system. Same number of each. It’s always bringing in fresh air and exhaust stinky/humid air from the bathrooms/kitchen/laundry rooms.
System is based on clean and dirty rooms. You supply clean air to the livingroom, other rooms, and extracting dirty air from the kitchen, bathrooms, toilets etc. This way you have controlled airflow in your house, meaning clean rooms will not get dirty air but dirty air and smells will be directed to the dirty rooms, which is what you want.
Very standard in European new builds. we use HRV's everywhere.This is even mandatory in Denmark, and in current house it's been installed since 1984, running perfectly good. Modern units do not need any boost switches here, humidity is controlled compared to last 24h levels, so whenever it rises 5% compared to 24h average, it boosts speed. It can even be connected to cooker hood (proven to work for 40 years). Can be controlled by CO2, VOC as well. By the way, gotta say this ducting you made Matt, is NOT most efficient at all. Too many bends very awkward stone-age metal ducting (corregated pipe is ok tho). Here we use metal pipes that connect with rubber gaskets, no tape or sealant needs to be used. The SFP value (power consumption) i would guess is quite high for this unit, here we have max 1000 J/m3 limit to avoid any crazy bad ducting design. I would like to hear your consumption and airflow, to really show how efficient it is, 120 W sounds very high.
We spend all this money water sealing, air-tighting, and insulating the house. Only to cut giant air intake holes, create condensation zones, and stuff hoses everywhere. Seems so counterintuitive where the product sellers on both sides of the equation are the only winners.
Thanks for sharing. Apart from the mentioned pollen, what’s the benefit of this system compared to opening windows in several areas around the house to allow fresh air to travel - especially using European windows that have micro ventilation opening position which minimizes cold/hot room temperature from escaping.
If you are "micro-ventilating" to minimize losing your conditioned air, then you are "micro-ventilating" the amount of fresh air coming in from outside. So what are the benefits of this system? - Filtering 100% of the incoming air - Temperature exchange to save energy - Distribution of fresh air to every room in the house, 24/7 - Extraction of moist air from bathrooms 24/7 People aren't used to the idea of a system like this bringing in fresh air, because we're all so used to leaky houses that ventilate sufficiently even with the windows closed. But if you'd seen earlier videos in this series, you'd see that Matt was maniacal about sealing his dwelling area. Because of that, "micro-ventilating" a few windows wouldn't be sufficient to provide enough fresh air for 5 people.
@@TrueGrantsta Thanks for replying. If I understand correctly, this ventilation system doesn’t replace cooling/ heating system. It probably connects to one and filters the incoming air, while it’s possible to add a filter to the hvac instead and save the cost, additional pipes and maintenance. Regarding the sealing that you mentioned: zip systems are great until nails from the siding and roof penetrate it. In general, we spend most of our time away from home and breathe unfiltered air throughout the day, and maybe this giant filter will have benefits in a highly polluted area, but I just don’t see how it’s making any difference otherwise, and remain with the micro ventilation option which probably loses less indoor air compared to opening the door when entering or exiting the house. Bottom line - it’s a house, not a zombie apocalypse bunker or a clean room manufacturing microchips.
To keep the control local add a local router and do not connect it to the internet. As long as you are within the distance of your routers wireless connection the app will work. If you do not like wireless there are adaptors for both iPhone and android phones to hard wire to and RJ-45 to the router.
This seems like a really cool system, however, as a Floridian it doesn't seem to allow me to open the windows during the cooler months due to our relative humidity.
I'm in Florida too. Not sure what your point is here though. The point of this house is to never open the windows. You can turn this system on high and in theory it will ventilate the home better than opening windows because all the air gets filtered.
Unless you can’t open a window or have severe allergies it’s just to much. Plus I never heard the cost? You don’t talk about the price on the home build.
People who have older homes (without central air) they only visit a few months out of the year, need this. The alternative is to hire someone to stop by the house several times a week to ventilate (open windows)... hope they don't forget to close the windows, trust them with a key, and that they don't steal anything. I'd rather pay for this technology
I'm comment bombing here, but I see so many issues with this system... No bathroom exhaust fans? So every time someone take a shower you need to ventilation the entire house? This means everyone should take a shower around the same time. You're essentially over-ventilating by doing this.
There is no such thing as over-ventilating. Bathroom has an exhaus and, it's always on. Boost mode is only needed if you have a poor diet or bathe like a hippo. There's virtually zero energy loss in Matt's climate. Unit will operate at 90+ % efficiency. Boost mode is > 150 watts and runs for 30 minutes. I'd personally set this to 15 minutes and include a humidistat trigger in lieu of a switch for the main bathroom.
I love the Michigan shoutout but we do have almost the worst of all climates. Brutally cold winters and incredibly humid summers basically 100% humidity everyday and temperatures 80-95 all summer, bypass would not be for us.
Does the unit have to be in a conditioned space like your attic or could it also be installed in an unconditioned/unfinished basement in the northern US??
It is always preferred to be in a conditioned space, as long as the space does not exceed 104F or below freezing the unit will work. It will have a a reduction in efficiency. So please make room inside the thermal envelope. I have a saying: at one time we figured our how to bring the fire inside to stay warm heat water and cook, we figured our how to bring the toilet and running water inside so lets figure out how to bring our ventilation inside.
I put the same system in my house about 2 years ago. Efficient, quiet and forgettable.Great system!
I would love to see more videos or a live stream with experts discussing HVAC. We are remodeling our old house and updating everything. Using closed cell foam and AeroBarrier. Hoping to get below .8 ACH/50.
All our local HVAC companies that have looked at our job have had no experience with HRVs. They haven't been able to answer how tight/when you need HRV. How to vent bathroom/range if you have HRV.
For anybody that wants my first hand experience here it is.
Built a 2ach50 barndominim super insulated double stud frame conditioned crawlspace the works.
I've been cooling and dehumidifying it while I built it with the hrv off. Electric bill in summer 30 bucks. (very minimal attic insulation still)
Moved in turned on the hrv. It takes air out of the bathrooms and brings air into the HVAC return.
Humidity went through the roof. The dehumidifier ran all day and only got the house down to 60 percent. Electric bill was on track to be 250$. Turned off the hrv and the humidity dropped 10 points in 3 hour. In my opinion it's a waste. Ymmv
I need this in my life! I'm definitely chasing this in my custom build.
Matt! What are you doing here
Do you get paid to promote outdated technology too?
Many years ago on Obsessed Garage, Corbett Lunsford and Brian Orr introduced us to home performance, blower doors, and ERVs
@@andreycham4797 what's outdated about this?
@@aayotechnology have you not heard about HRV with integrated heat pump?
Ultimately Zehnder needs to bring the unit from Europe that integrates a dehumidifier with the system to the US: the ComfoCool Q, not just the ComfoAir Q.
As a person that has a Zehnder unit in the US, I couldn't agree more. We could not achieve less than 75% humidity in our home during the warm months. We have to have a separate unit to do the job now. Built in would be amazing.
As much as we all would like an dehumidifier on an ERV in many climates it does not work. When we look a the volume of air brought in and the amount of water that can be removed from the volume of ventilation air in humid climate. It would be less than the water that gets in by as air leakage, diffusion, people exhaling, perspiring, showers, cooking, plants, pets, capillary from the ground, washing dishes, did I miss anything? So even if the dehumidifier could remove all the water from incoming ventilation air it would not be enough in many cases.
I am in an arid climate. I need a whole house humidifier.
These systems are crazy to me. I grew up with hot water baseboard heat in Michigan's upper peninsula and gas forced air in Wisconsin. I love the idea of each room being dialed in and not just guessing
What is a bit odd is that the system when triggered for the bathroom seems like it will send the WHOLE unit into high speed mode, and not just the single room that it is needed as the whole system is balanced at a room level by what is essentially manual dampers. There could be a potential for efficiency improvements.
Thought this as well.
Have to keep the house pressure balance.
That's fair, but I would imagine the difference between boost and maintenance mode is pretty small and the energy use is negligible.
Putting the unit into boost mode is just going to proportionally increase the CFMs at all registers, which includes the bathrooms. I understand what you're saying about how only putting bathrooms into boost mode would increase overall efficiency, but to my knowledge, there is no fresh air system on the market that can do that.
@@anDWandy True. I do believe there is usually a localized return path to the main unit in the same space, which would keep that pressure balance as long as the return stays in step with the source. I could be wrong though.
It would be cool if for the cooktop air system, turning on the exhaust fume hood could send a low voltage signal to the ERV, which would trigger the ERV to increase supply air CFMs by how ever CFMs the cooktop exhaust hood is removing. Yes, the ERV would not technically be balanced during this moment, but the whole house would still be balanced technically. I would imagine one of the reasons for not doing this is that the cooktop exhaust hood removes too many CFMs that the ERV couldn't make up. Still a cool idea though. Great video!
I think in an earlier post, Matt mentions that he has a makeup air register for the hood that opens when the fan is activated.
RenewAire has this capability with their control system option.
Originally my Zehnder rep told me it would but after much discussion with the engineers they said it would not. I don't see how it couldn't detect the negative pressure at least up to its capacity and shut down the other exhaust temporarily to compensate, but it doesn't work that way. In general it actually isn't as smart as you might think. For example, if you use a boost switch in a room it doesn't just boost that room, it boosts the whole house for that time period.
Fabulous system, but expensive, and I'm not sure if them charging you for airfare is a great perk.
No, I don't think it is. It would be nice if they would make the information on how to design the system public and the components purchasable by consumers. That's probably the only way this system would end up in my house, but it looks awesome!
Hey Matt, great series. If you were to eventually sell this home what kind of documentation of all the systems (e.g. HVAC, etc) would you put together for the new owners? Curious because I'm sure most home owners wouldn't know where to start if something stops working.
I think he's expecting to pass it to his kids.
This is what my opinion
1) air exhaust on the ceiling
2) air supply on the floor wall.
I got the idea from Matt's ERV videos to do something similar when I built a large house and had the HVAC guys install a 300 cfm ERV which pulled air from bathrooms and laundry rooms and put fresh air in bedrooms. In addition to the whole system percent timer, they created a circuit board with zone dampers in the duct work which defaulted to fully open that worked with analog bathroom exhaust timers so that when a bath room timer was activated it would partially close down dampers going to other bathrooms (two laundry exhausts always remained fully open) and therefore pull harder from the offending bathroom (or bathrooms if more than one was running a timer concurrently) until the timer ended. The 'bath exhaust timers' would also activate the ERV if it wasn't already running based on the percent timer. It was silent and worked EXTREMELY well to get rid of smell. That being said, I missed the noise created by the exhaust fan so it made using the bathroom a little less private.
So you filter the bathroom air and recirculate it rather than exhaust it from the house?
@@aayotechnology No, the ERV removed house air from bathrooms and the laundry rooms and put that air outside while bringing in fresh air and putting it in bedrooms and near large return air intakes to get distributed through out the house.
Chris is Awesome! Thanks for the great explanations.
System looks great! The only questions that I have is what happens if you have a hurricane, tornado or snow storm and you loose power in your area for days or a week or two? Will you have to open your doors or windows to let the air circulate out the CO2 that’s trapped in your home?
I would assume he has a back un generator installed for power outages.
@@rory644 for sure, but how big does that generator need to be? What else does it run? And do you have enough fuel to operate everything for a prolonged period of time?
Good grief, watch his other videos! He has at least one about the generator he installed, and I think he helped neighbors when the power was out for several days last winter. If you think he's gone to all this trouble without considering emergency situations, well, think again.
@@CitEnthusiast my point is simply that there a lot folks out there that aren’t taking that into account. Just looking out for others to help make sure they think it through as well.
Have a room full of plants! all set haha
Why is a whole house distribution needed? Why doesn’t it just feed the HVAC, and let HVAC slowly circulate even when temp change isn’t needed?
Mat, unless I've missed it, could you do a show on your induction stove top. Maybe after your wife has used it for several months. I have used counter top induction for years. I've heard good things about stove top units. I would appreciate a deep dive on induction. Also what type of oven you are using. Thanks
The only type of dryers allowed to be sold in Europe are the condenser types. Like you have installed.
As an American I find them inferior to our gas powered dryers. Comparable gas dryers are not very energy efficient but the speed and results are great.
Have you compared the results of the two?
Dry your clothes on a clothes line. Problem solved.
Never used a gas dryer, how do the clothes feel after drying vs conventional electric?
@@Raymond-mk8cb Not in humid climates Ray.
We have a Miele condensing dryer in the garage. It works great, built like a brick s********...German quality I guess. Decided to go with one for our remodeled house didn't have a vent installed in the garage. The Miele also uses a basic 15 amp household 120V outlet, freeing up the NEMA 14-50 dryer outlet for our EV charging. Most likely saving cash on both ends over retrofitting for a vented dryer plus second 240V EV outlet, plus the energy savings on drying (we're seeing 600-800 watts on the dryer).
Downsides:
- The model we went with is small, great for a small family household, but will become apparent with more laundry.
- it's a closed loop system, with 3 filters. Two of the lint filters require frequent cleanings, they are sandwiched together for ease, but for proper drying they should be cleaned between loads or cycles. We keep the garage vacuum near for easy cleaning. The third filter is essentially a sponge, and should be cleaned or washed infrequently.
@@macthemec Warm and fluffy. About the same.
The real question is do we stay cheap and burn stuff and vent it to the atmosphere (coal power plants, gas dryer and water heater), or do we have expensive renewable power and very complicated systems for efficiency?
Hi Matt, I'm a builder from Australia, Melbourne and we love your work. Given your extensive knowledge in this subject I'm wondering how to ventilate timber frames naturally with ICF type walls? We use Dincel or pvc concrete filled walls for basement constructions. Would you recommend steel frames? Or is mechanical ventilation the only option?
General method is brick veneer facade on timer frames, which has obvious limitations with respect to insulation but evenly spaced weepholes or vents ensures no moisture build up against timber frames.
If I ever build my own I will have that system great engineering
OOOoooonnnn the BUILD shooooooowwwwwww!!!
Can you imagine how fast those little filters will clog up and the constant cleaning and refreshing required of the filters by the homeowner?
So the return is right where the moist shower air will exhaust? I can see that hose looking pretty in a few years.
Hi Matt,
I LOVED this video.
Just one question related to your "Balanced & Distributed" system...
Are you somewhat over ventilating your home?
I know ASHRE doesn't give credit for a Balanced & Distributed system... but Doc Joe Lsebrick's BSC-1 does... and on my house it ended up being a lower overall CFM requirement for our home as compared to the ASHRE Standard.
Cheers,
Eric
It would be interesting to see a chart that ads up all the additional cost for all this fancy tech needed for a super tight house vs just building the house normally and losing a little heat
Build to 3-5 ach 50 and leave out the fresh air system. Trust me these systems eat electricity big time
This is not about energy at all. Matt touches on this in the beginning of the video. Bring in fresh air where and when you want it. Right now, I live in a place where the bedroom gets pretty warm over the course of the day in the summer, and I can't tell you how many times I open the window at night and but the temp inside doesn't budge. It can be 20 degrees cooler outside, I'm not feeling any of that if there is no breeze AND it's not blowing in the right direction. Sometimes the stars have to align too... This is about designing for control and optimal health and in the process not throwing away all of your conditioned air. @@justinballard7242
this is great, love the concept, and being efficient and having control, but having to always change a bunch of filters and clean things out, it's just one more piece of maintenance to a house. plus if you loose power, or there is a surge, is the unit protected? does it remember all it's settings? With my current 'drafty' budget house, there's only 1 filter I have to change, and I don't have to get on a ladder to do it.
The filters for intakes is an extra just to keep your ducts clean which should be in every home (bathrooms, return air etc) It would be like having filters in intakes for a regular system.
Twenty minutes of maintenance every 6 months for fresh air in your entire home all the time? I bet you can handle it. :)
This maintenance will be annoying. Seems ok right now, since this is all new. But give it a few months and you will find yourself wishing you hadn't. It's much much easier to place the filters at floor level where you can reach them.
The placement of the in and out units allows heavier particles to settle to the floor, if it's as balanced as they're saying.
I want to know how this compares with ground source heat pumps in terms of payoff, power requirements and efficiency.
This is obviously a simpler setup, although tuning is likely the key after the tight envelope.
Geothermal payoff is about seven years. The Federal tax incentive, if it continues, pretty much pays for the drilling and tubes. Provided you aren't above geologic voids it would finance the grouting of those tubes for continuous contact with the native formations.
A customer can see a bunch of money go down a hole in karst, or dissolution environments. Good contact is key for heat transfer.
The story behind the mini split. Is it for the basement?
I may have to find the installation video.
@@richavic4520 there really is no roi for this though... It is simply fresh air supply because it's a tight house. I'm not sure how you could measure how much it saves when it isn't producing heating or cooling.
Nice setup
Totally want this for building my dream home!
Matt, that looks like a well-engineered system but I think it's overkill. The central air handler can mix & distribute fresh air right along with the heat/air and thus avoid all that extra expense for separate ducts. A variable air volume system with direct digital control can deliver air continuously in just the right amounts to any room that needs it. Co2 sensors and dehumidify/humidify control give precise whole house control. And the maintenance is all at the central location. A few Phoenix valves can do the job. ua-cam.com/video/003m3QD7UVs/v-deo.html
Excellent point. We have used this system in a few of our builds because the client really wanted it. However, we generally go with exactly what you just recommended. Matt is doing a fine job on his build at any rate. 👍
Unless you’re using ducted mini splits….
@@dandan1364 Ducted? The whole idea behind mini-splits is 1 unit for 1 zone, multiple units for multiple zones. A variable speed central system can have zone dampers to control multiple zones.
@@ToIsleOfView That was 1st Gen mini-splits. Modern units can have multiple zones with 2+ compressors in the outdoor housing. Some, like Mitsubishi, also have manifolds to direct the output to multiple locations. They're moving heat around the home to where it's needed instead of just bringing heat in or sending it out like the early tech did. Obviously, they can still do that--send heat out or bring it in--as a part of the process.
At Matt's home, for example, he used mini-splits for heating and cooling, but a Zehnder ERV system for ventilation (fresh air, enthalpy management, exhaust). There is no 'central air handler' other than the Zehnder. No sheet metal ducting, etc.
Matt, did you install a barometric relief damper into your kitchen hood exhaust line? Even with the fan off, it will have a natural flow of air out otherwise...
He ince showed ut had an electronic dampener
@@chuckley54494 Yes, there is a damper on the make up air, so air wont come in when not in use. I am wondering about the exhaust line? The pressure from the ERV will force air out of the house if he does not have some sort of damper..
Excellent review
How are you monitoring and verifying mold forming inside the system and or hoses. Wild
I'd love to see a CO₂ (carbon dioxide) sensors included in the system with automatic increase in fan speed for the CO₂ increases like during a party on a cold night.
Along with pressure sensors to tell you when to change / clean the filters. For this kind of money, a few transducers should be included.
The system supports up to four CO2 sensors and can boost the fan speed if increased levels of CO2 are detected. It was mentioned in the previous video about the Zehnder install at his house (prior to this commissioning one).
Not commissioning, this is start up. After startup and air balancing (TAB) is done. After all there start
Commissioning process:
1) Cx BOD (Basis of design) document review that BOD meets OPR (owners project requirements).
2) Cx design review
3) Cx submittal reviews
4) Cx review if receipt of until in site, how its stared, boxes in good condition, all parts and options there.
5) Cx installation inspection.
6) Cx pre energization inspection.
7) Cx pre functional inspection
8) Cx Functional commissioning after unit start up and TAB air balance reports completed and reviewed. Test all unit functions and performance.
9) IST interested System test. Test all systems with everything's ng in home completed to verify all systems function together
10) Cx Seasonal commissioning, winter fall, summer.
11) 10 month warntee review if all commissioned system, retesting all, all definitely ciencues reported so full fixed before GC 1 year warntee expires.
12) CX periodic recommisioning check all functions, review energy use and system changes.
Matt is world famous, I can say *"I knew him when"* he only had 30k subs.
I like how they have an expert setting up the system but it would have been cost effective to tie the ERV into the air handler and have that continuous running and balance one system. for bathrooms use a timer and a posh grill so the ERV favors pulling air from specific bathrooms. The HRV/ERV debate, we generally use a ERV in a radiant heated house because they have have lower humidity levels and a HRV would make the air too dry here where its humid.
Running ecm 80 cfm 24/7 piped from outside through a three filter staged air box directly into furnace plenum intake then filered twice merv 12, ti02 filter then 4 uv lights above and surrounding a coil and one in center a coil, timed. Three class 2 medical filters running separately at 80 cfm x2 and one at 100 cfm. Not much more i can do. Electric bill 150 mo. All electric. All led lights. Need to install heat pump water heater sitting in box in garage. Maybe solar air heating to heat partially conditioned crawl space, no floor insulation. Bare cinder block surround skirting but foam sealed to house rim joist, platic liner on ground. Bubble foil wrap on all venting. No flexible venting or garbage yellow or pink moldy stuff. Subfloors painted with kills and hytech ceramic additive [r7 est.]. Need to seal and insulate cinderblock skirting and one more wrap of double bubble on ducts, paint underside of subflooring with kilz and hytech lay down foil infrared blanket on ground the ill b done. All protrusions in floors, walls and exterior outlets foamed. Hvac closet walls foamed three pound pourable to prevent condensation into walls and seal cavity. Hvac pan double insulated, double panned with water sensor, antimicrobial. Drain line pressurized to prevent fouling of drain line, cost gaurd style, and backdraft thru line also skupper check valve. Petot tubes to follow to ballance air flow with filters. Need better butterfly vent assemblies in bathrooms and on micro vent. Need closable chimney cap. Currenly fresh air intake on fireplace foamed shut as i dont use it but can open it if needed. Furnace motor ecm constant run to circulate air it has prefilter and draws some air from water heater room which has its own wall mounted filter next to refridgerator to capture humidity and warm air from ice box motor. Shower or bath cavities vented and water alarmed. Lennox elite heat pump has its outdoor coil elevated off of ground, sided and roofed in its own "doghouse", screened and protected. I have video of it on my channel hvac coil doghouse. All lines wraped with armaflex and where exposed to weather 3m extreme weather hvac metal tape. Thermostat staged 66 to 70 f.
Excellent stuff bro
You can get 95% the effect with a lot less cost and complication using ERV, dehumidifier, and multi variable blower.
The Messana/HiDew unit incorporates dehumidification with air balancing.
I enjoy the theory of fresh air system. So much off gassing from furniture, appliances, flooring, cleaning chemicals, etc. In our petrochemical world, plastics especially the ERV plastic tubing gassing has its issues. My brother is a chemical engineer. European cars must meet parts per billion off gassing in cars(plastics, etc) vs USA standards parts per million. It is hard to completely get away from air pollution. I live in Hawaii but we all still breathe the same air. Enjoy your videos.
Why not just install a couple 6 inch Merv 15 plus or Merv 16 air filter with an ECM inverter Drive HVAC and combo unit and run it 24/7 with an air exchanger?
@BuildShow... at the 16:30 mark, you have duct tubes all over the floor in the attic. In one of your other videos, you featured a conditioned attic, where the client was an engineer, and he used a CNC machine to punch out 4 inch holes in a sheet of plywood cut approx 2' x 3' so that the plywood could be mounted on the rafters, and the ducts routed through the punched holes to keep it organized and off the floor. Can you help me find the link to the video I'm remembering? Thanks so much!! I want to share it with a client.
WAIT... Never mind... I found it!!
Coming in way late for this video, but I am really impressed. Thinking way outside the box, maybe, I was wondering if there is a kill switch, or if there is a need for a kill switch in case of fire to remove that constant fresh "breeze" and reduce/remove any additional fuel to a fire?
for an upgrade, you should go with a Bora downdraft extractor for your stove that simply filters the air and keeps it inside the envelope. creating a penetration for your range exhaust is not wise in a near passive design...
Was going to ask the same thing… why not just run a whole house purifier thru the hvac? I understand it pulls air from the bathroom but seems a lot cheaper, less hosing and less hassle to just run a Santa Fe purifier and dehumidifier.
What happens to air quality in a house that tight if the power goes out?
You have to open windows after a while. My house is insanely tight and uses a far simpler system to bring in fresh air (opens outside vents for 5-10 minutes out of each hour and runs the central air fan to pull the air in an distribute right through the normal vents, standard air returns work to cycle the air inside the house, one external vent opens to let some air out to keep the pressure balanced)... when the power was out here for four days we noticed stale air after the first day and cracked open a couple windows (in -6F weather that's not terrible pleasant).
Let my kids come over and they will leave every door open or slam them shut to force air movement.
Love this system. Want one!
I would absolutely want this if I was building a new house. It looks like it would be a nightmare / ton of work to retrofit in, though.
A killer job on your home.
Matt likes a little bit of bathroom with his cabinets!
Ah, so this is how they make rich people air
Matt, I will be curious to hear how you like those Miele washer and dryer sets. My Zehnder system is about 75% installed and just started thinking about what to do for ventless dryer. All roads seems to point to Miele and Bosch for heat pump dryers, but I don't know anyone who has one. Everyone I know who has a condensing dryer hates it, so I'm crossing my fingers that these new heat pump dryers cut the mustard.
One problem is none of the heat pump dryers are as big as traditional US dryers, so forget about trying to dry a comforter. Someone used to make a large heat pump dryer, but it's been discontinued. It will also take a long time to run, as the hot air isn't nearly as hot as gas or electric. If you are OK with more frequent small loads which take longer to run (and the filter cleaning), it is more efficient to operate and doesn't send conditioned air outside.
We've been using a Bosch heat pump dryer for years now and we love it. It does take longer than an electric or gas dryer. Most loads take 80min or so which isn't a big issue for us. Being able to place it anywhere and not worry about venting is great.
I want to know if it is necessary to attach a standalone humidifier to the Zehnder system for more hot & humid regions like West Africa (humidity is consistently over 75%).
Depends. I live in an area with 90%+ humidity in summer but my house is so dry from the AC running all day every day that grapes turn to raisins on the kitchen counter. However, Matt has an older video showcasing an AprilAire in-line dehumidifier so I'm guessing in a lot of cases you would want a dehumidifier. Remember you want to keep your house at 40-60%
@@Eric998765 I plan on building a passive house to keep the expensive conditioned air as long as possible. Considering I will be using the AC consistenetly to maintain the ambiant tempreture I guess a separate humidifier might not be necessary.
@@DanielDuedu With a passive house, much of the air conditioning load is from the electrical use indoors, and a small amount for leakage and door opening. This means a much smaller A/C unit is required, which may not dehumidify enough to meet desired humidity levels, thus requiring a standalone dehumidifier.
@@johnhaller5851 Thanks for the reply but won't a smaller unit take longer to reach the desired temperature as compared to a bigger unit that will reacher it faster and cut the power. This effect is amplified in a passive house because it can sustain a set temperature longer.
@@DanielDuedu Yes, a smaller AC unit will run longer than a larger one. But if even a smaller AC unit isn't needed much to reduce the temperature, the humidity levels will still go up because water vapor is also trapped in a tight house, and respiration and bathing will increase humidity over time. If the temperature is correct, only a dehumidifier can remove that excess humidity. If the outside air when changed to indoor temperature will have a lower relative humidity than the target indoor humidity, then the ERV can be used to lower the humidity.
Does it actually keep up with shower steam though?
Yes, easily.
@@Tommeehr all that humidity from a bathroom makes it outside the house? Or does much of it collect in ducts and filters?
@@aayotechnology it goes outside. Part of the moisture can be returned to the input stream of the air since this is enthalypy unit and it recovers part of the moisture only if inside air is dry, it is natural process happening on the heat exchanger of the unit.
How is this routed to the first floor rooms? Did you have to build chases into the architectural design to accommodate going from an attic space to a first floor/basement?
Hi Matt, Since you moved in, how has it been using only Zehnder in the bath/shower to evacuate steam? How much CFM will it be with boost switch activated?
What an amazing system!
Except for the mini split above the stairs [9:43]. Those do have a screen [I wouldn't call it much of a filter] that needs occasiomal cleaning, plus... when the remote pukes on you, physical access is required to try a reset or manual activation. I know zero people that keep scaffolding handy for their homes - just never happens. An architect dreamed this up???
@@flinch622 valid point. It's just for extra cooling when there is a lot of company. I'm pretty sure it's not intended to provide added filtration. I think I might be able to reach it with my little giant ladder.
Massive overkill. I love it! 👍
Great video! What's the long-term maintenance requirement for the tubes? Do they need to be cleaned by a pro at certain time intervals?
Is there an option of treating the fresh air with UVC and or atmospheric hydroxyls?
I like the UV idea - sure fire way to knock back mold spores. It needs an easy access location as lamps need annual replacement. Still need a filter to deal with the bulk of nuisances however.
A mini-split way up there on the wall above the stairs. Talking about making it difficult to change that filter.
That mini split is only used in high demand, he mentioned it another video.
LMAO
10:30 seems like you coulda just put one of those zender vents behind the matching faceplates? I assume they didn't fit? Looks like they could have by the looks of it. (You would have to make a manifold or something.)
You are commissioning the system with dirty filters ? Sounds like these readings are going to be biased. For a normal system might not make a difference but since you are being so exact I wanna bet there is an offset somewhere... Very cool system none the less !
Good vid, and whenever specialized gear arrives to a project tha always brings up "why" - reasons can vary greatly..
You know, it's funny: we seem to need to purchase more and more specialized equipment [often electric] as the "eco" mantra is followed, and housing is not immune. There is a subtle difference between that and purely engineering based efficiency solutions - beware of mindless marketing. Foe example: I suffered upon a LEED website last week and observed the business of a rating system is largely politicaly defined [salted with incorporated references to ashrae, EN, etc standards to imbue apparent engineering legitimacy]. As a sidenote, bankers [such as Dimon] have salivated over carbon credit schemes in the past. Why? Because there is nothing to ship or store - zero capital investment for brick and mortar required, and with government fiat status comes...zero liability. Good stewardship of resources is important, but you have to filter through the fog. If you are building for third party "credits" and not results... well, good luck with that.
I have a loop of Matt saying tight envelope that I go to sleep to every night.
Want one of these but they are ridiculously expensive in Australia. Local importer must have a huge markup
Same from products imported from AU to EU, they double or triple in pricing 🥲
This is awesome. Too bad my 1945 house leaks like a sieve so I can't have awesome things like this.
I see that you use Mitsubishi systems also, what are the differences ?
Only thing that could be more entertaining is if Gary did the commissioning. Feather in hat and everything
Matt-what brand are your two vents to outside for this system
Why not restrict/adjust the CFM at the manifold connector rather the register? If you did your adjustment at the manifold you could use any register.
MKTech
This can be done by installing a Zehnder filter box between the manifold and sound attenuator. This will allow balancing the unit with any grill as long as a flow hood can be placed over the grill. I have clients that do this with linear diffusers. They build a split boot where part is for heating and cooling and part for ventilation. And yes the same linier can have a return ventilation and supply H/AC. As long as the velocity for the supply air is high enough it will blow the air into the room and mix before the air goes back to the return,
So what did this system set you back?
There are filters on each return duct... 😳Those are definitely going to be forgotten about over time. Matt might not forget to clean them, but if he moves, they're never going to be touched.
Nah, he will give the new owners a call every 6 months and remind them... Or they could program the fancy lights to sound an alarm every time they need changing.
They need to start putting filters on fart fans. I'm not a contractor and I've seen a bunch get disgusting over the years.
With the Q unit when the static increases past a point due to plugged filters an error will occur. If the app is installed on a phone a notice will sow up on the app icon. As well as an error on the controller will show up.
They may want to design a few different interior covers as they find situations like the one in the living room
This sounds suspeciously like another expesive gadget to lose its memory with every power surge or failure. Did I hear, fifty interior filters to remove and wask every 3 or 6 months? Filters that you need to stand on a ladder to access?
No, it's ok. You just need to get sponsored. Good to go!
@@MrTexasDan 😂😂😂 yeah this is nuts for an average homeowner.
Well they are mechanically adjusted to the memory should last with power outages, but I don't want to tell my builder to put all those tubes in.
Only the intake tubes have filters. So primarily just the bathrooms.
What memory, what are you talking about?
Do you then just turn it off or change modes, for those days when you want good old fashion open window ventilation?
You do not need to do anything, you can open window. You can put the unit into away mode if you wish.
Some people just leave it at its medium speed and others choose to turn it to the away mode. Then again some find with proper filtered air they will never open the house again.
@@andrewwahl4503 this is how it is at my place. I have the system for 4 years and no need to open windows anymore. And that is the point, you have fresh air 0-24 while system is recuperating energy that would otherwise be wasted.
02:21 Hey Please Where can One find that Muffler/Air Distributor Thing With White Tubes coming out of it? And What is that Box Called?
Can you show/explain how the return air is handled?
I have seen options for wall grill vent, bottom door solutions, door seal solutions, door frame solutions, but I am curious how you solved that in your house.
The Zehnder has supply tubes and return tubes. It’s a balanced system. Same number of each. It’s always bringing in fresh air and exhaust stinky/humid air from the bathrooms/kitchen/laundry rooms.
System is based on clean and dirty rooms. You supply clean air to the livingroom, other rooms, and extracting dirty air from the kitchen, bathrooms, toilets etc. This way you have controlled airflow in your house, meaning clean rooms will not get dirty air but dirty air and smells will be directed to the dirty rooms, which is what you want.
Very standard in European new builds. we use HRV's everywhere.This is even mandatory in Denmark, and in current house it's been installed since 1984, running perfectly good.
Modern units do not need any boost switches here, humidity is controlled compared to last 24h levels, so whenever it rises 5% compared to 24h average, it boosts speed.
It can even be connected to cooker hood (proven to work for 40 years). Can be controlled by CO2, VOC as well.
By the way, gotta say this ducting you made Matt, is NOT most efficient at all. Too many bends very awkward stone-age metal ducting (corregated pipe is ok tho). Here we use metal pipes that connect with rubber gaskets, no tape or sealant needs to be used. The SFP value (power consumption) i would guess is quite high for this unit, here we have max 1000 J/m3 limit to avoid any crazy bad ducting design. I would like to hear your consumption and airflow, to really show how efficient it is, 120 W sounds very high.
We spend all this money water sealing, air-tighting, and insulating the house.
Only to cut giant air intake holes, create condensation zones, and stuff hoses everywhere. Seems so counterintuitive where the product sellers on both sides of the equation are the only winners.
So would this type of system eliminate dust ?
Also what would you do if you had a standard type dryer
Thanks for sharing.
Apart from the mentioned pollen, what’s the benefit of this system compared to opening windows in several areas around the house to allow fresh air to travel - especially using European windows that have micro ventilation opening position which minimizes cold/hot room temperature from escaping.
If you're in an area with low humidity and low pollen, opening the windows can be a great idea. Outside air isn't always "fresh" air.
This is exactly what we DO NOT do in Europe.
If you are "micro-ventilating" to minimize losing your conditioned air, then you are "micro-ventilating" the amount of fresh air coming in from outside.
So what are the benefits of this system?
- Filtering 100% of the incoming air
- Temperature exchange to save energy
- Distribution of fresh air to every room in the house, 24/7
- Extraction of moist air from bathrooms 24/7
People aren't used to the idea of a system like this bringing in fresh air, because we're all so used to leaky houses that ventilate sufficiently even with the windows closed. But if you'd seen earlier videos in this series, you'd see that Matt was maniacal about sealing his dwelling area. Because of that, "micro-ventilating" a few windows wouldn't be sufficient to provide enough fresh air for 5 people.
@@TrueGrantsta Thanks for replying. If I understand correctly, this ventilation system doesn’t replace cooling/ heating system. It probably connects to one and filters the incoming air, while it’s possible to add a filter to the hvac instead and save the cost, additional pipes and maintenance.
Regarding the sealing that you mentioned: zip systems are great until nails from the siding and roof penetrate it.
In general, we spend most of our time away from home and breathe unfiltered air throughout the day, and maybe this giant filter will have benefits in a highly polluted area, but I just don’t see how it’s making any difference otherwise, and remain with the micro ventilation option which probably loses less indoor air compared to opening the door when entering or exiting the house.
Bottom line - it’s a house, not a zombie apocalypse bunker or a clean room manufacturing microchips.
Being able to control it with my phone is great, but only if it all stays local. Also, what happens when they stop updating the app for your system?
To keep the control local add a local router and do not connect it to the internet. As long as you are within the distance of your routers wireless connection the app will work. If you do not like wireless there are adaptors for both iPhone and android phones to hard wire to and RJ-45 to the router.
10, 20, 30 years from now the software will be forgotten about and unsupported.
Would like to know the cost, and what alternatives there are
Costs?
This seems like a really cool system, however, as a Floridian it doesn't seem to allow me to open the windows during the cooler months due to our relative humidity.
I'm in Florida too. Not sure what your point is here though. The point of this house is to never open the windows. You can turn this system on high and in theory it will ventilate the home better than opening windows because all the air gets filtered.
@@McDylanNuggets Thanks for clarifying. There are times I like to open the windows during cooler weather and listen to the sounds of nature.
@@tomcarrow it does not lock your windows. They will still open.
Unless you can’t open a window or have severe allergies it’s just to much. Plus I never heard the cost? You don’t talk about the price on the home build.
People who have older homes (without central air) they only visit a few months out of the year, need this. The alternative is to hire someone to stop by the house several times a week to ventilate (open windows)... hope they don't forget to close the windows, trust them with a key, and that they don't steal anything. I'd rather pay for this technology
I'm comment bombing here, but I see so many issues with this system...
No bathroom exhaust fans? So every time someone take a shower you need to ventilation the entire house? This means everyone should take a shower around the same time. You're essentially over-ventilating by doing this.
There is no such thing as over-ventilating. Bathroom has an exhaus and, it's always on. Boost mode is only needed if you have a poor diet or bathe like a hippo. There's virtually zero energy loss in Matt's climate. Unit will operate at 90+ % efficiency. Boost mode is > 150 watts and runs for 30 minutes. I'd personally set this to 15 minutes and include a humidistat trigger in lieu of a switch for the main bathroom.
Can the public buy the Zehnder insulated rigid ducting?
Who manufactures your pull down stairs? I have 11ft ceils with a very heavy wooden ladder and I am looking for something much easier to use.
Matt did a video on the attic stairs a few months ago.
ua-cam.com/video/zPXdrmks6x0/v-deo.html
Does this system effect the noise floor in the house???
I love the Michigan shoutout but we do have almost the worst of all climates. Brutally cold winters and incredibly humid summers basically 100% humidity everyday and temperatures 80-95 all summer, bypass would not be for us.
I’m sorry but the split air on the staircase wall is hideous looking, same with the triple stack of switches in the master bathroom.
Personal family? Does Matt have a Business Family?
Is this feasible or worthwhile for an existing home thats not as air tight as Matt's? I've got a ranch with a finished basement.
Do you have a fresh air or extra in the attic space?
Grade II insulation on that wall behind the Zehnder unit! Not a six sided assembly, therefore not grade I though it looks like a good install. 😬
You gotta show me your hvac system please 🙏
Does the unit have to be in a conditioned space like your attic or could it also be installed in an unconditioned/unfinished basement in the northern US??
Its always best to have any air handling equipment inside the conditioned space
It MUST be in conditioned space.
It is always preferred to be in a conditioned space, as long as the space does not exceed 104F or below freezing the unit will work. It will have a a reduction in efficiency. So please make room inside the thermal envelope.
I have a saying: at one time we figured our how to bring the fire inside to stay warm heat water and cook, we figured our how to bring the toilet and running water inside so lets figure out how to bring our ventilation inside.
Tommeehr i wish this was mandatory