Asian HVAC Innovations and How to Evaluate for Homes: ERV + Dehumidifier Combo

Here was a cool client challenge in SE Asia, exploring the dynamics of his home and the possible products that might fix his issue. The piece of equipment we ultimately landed on for his solution is somewhere in here (though very hard to find via English language site apparently):
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[@nathanbarry9534]

This seems useful in any humid climate, it seems like a good fit for the American south as well.

[@bent2331]

Do you have any thoughts on why this doesn't exist for the US market? It feels like the workaround we use (dehu into supply side) is a suboptimal solution.

[@hanamanova5514]

Most of contractors are not interested to offer such solutions in the US. We need to think with our own head before shelling out money for HVAC with 95% of HVAC contractors.

[@shubinternet]

But yeah, living in Austin, TX - I would say that an ERV combined with a dehumidifier could be a great solution! Thank you!

[@ncbarndobuild]

Interesting. I am going to keep this video in mind for our consultation next month.

[@HomePerformance]

Nice

[@TomMorris1]

In the UK it’s pretty standard to tie the bathroom fan operation to the light switch. After the light is switched off the fan will either stay for a period of time or more sophisticated ones have a humidity sensor to determine when to turn off. I think this is a better approach than separate switch for bathroom fan that you might forget to turn on.

[@johnhaller5851]

I've been thinking about something similar with smart home technology, but I need to get my bathroom vented to the outside instead of just dumping it into the attic. I have a separate switch for the shower light than for the toilet light, so it could use different algorithms for each switch.

[@global2829]

@@johnhaller5851 I'd think a good approach would be an occupancy sensor and humidity sensor. If someone is only in the bathroom for a short amount of time, don't run the fan for that long after they leave. If they spend more time, run it for longer. And also run the fan if the humidity is above a threshold.

[@EclecticBablefish]

For everyone saying you need this in the USA, it's available. I live in Philadelphia and have seen 2 buildings with the MINOTAIR PENTACARE-V12. It's made in Quebec and there are some cool videos about it on KZbin.

[@bent2331]

the Minotair is a bit different, see @superspeeder comment below. It's also exorbitantly expensive

[@charlespaine987]

The more complex you make the system the more maintenance /energy required. The vast majority of common people can’t or won’t do or have done the REQUIRED maintenance (money). Those Units are seldom put where they can easily be serviced . RULE 1 maintenance if it is not easy it will be neglected. Like most ideal systems most are NOT Practical in common use.

[@joeshmoe7899]

Installing a bathroom exhaust fan occupancy switch solves the kids not turning it on. But recirculating bathroom air, ewwwww.

[@tweake7175]

Nice idea for tight spaces, but i would use separate gear simply for reliability and replacement purposes.

[@ZergZfTw]

That's basically a residential DOAS system. The CERV2 is about the closest equivalent we have in the US. I would like to build a system like this some day, but with hydronic coils, and maybe a small desiccant wheel to get the supply air really dry.

[@dehutech1072]

We already have residential hydronic DOAS system and DX DOAS system.

[@Werdna12345]

1:10 I got a portable dehumidifier that drains with a hose and doesn’t get a bucket gross

[@grigorkyokuto7546]

OMG, I live in a nearby city, will likely contact you soon!

[@dehutech1072]

Wow! What an honor!I am from LUKO.Actually we have updated FD-E and FD-S series in 2023 with better technology 🎉🎉🎉

[@HomePerformance]

I like your work, buddy. Keep it up!

[@dehutech1072]

@@HomePerformance Thank you very much!

[@beurky]

Anyone find how to buy this in north america? Pricing? I tried to find this or similar on AliExpress, and couldn't find anything.

[@dehutech1072]

I am coming 😊😊😊

[@CommonSensePH-yq3sx]

This is my problem. We’re currently planning for our house. I’ve talked to several mechanical engineers and no one seems to understand this. We’ve had several ducting plans but none of them seem to understand this.

[@HomePerformance]

I’m available to consult if you need it buddy. buildingperformanceworkshop.com/video-consulting

[@ecospider5]

Bathroom doors are only for guests

[@billcunninghame8554]

I'd love to be able to add an ERV to our three story townhouse. However, HOA rules won't allow any penetration of the envelope. I'm guessing that isn't an issue in this case.

[@HomePerformance]

They just have to petition the Chinese government I think- should be a piece of cake

[@johnhaller5851]

You already have a penetration for the bath fans, probably for each fan. If you combine two exhausts into one penetration, and the other one exhaust penetration is far enough away from the plumbing vents and the other exhaust penetration (40 feet, I think) you could repurpose one of the exhausts as an inlet. Unfortunately, plumbing vents tend to be close to exhaust vents because there's always a fan near a toilet. Another possibility is to get a heat pump dryer and repurpose the dryer vent as the inlet if it's far enough away from the exhausts.

[@superspeeder]

YES!!! I’ve been saying we need an HRV with a heat pump / dehumidifier built in for a long time! Have four coils and directional valves so you can cool/heat/reject into or from any airstream you want. In the summer you cool/dehumidify incoming air and reject the heat to outdoors. In the winter you can capture the small remaining heat in the exhaust air and use it to heat the incoming air on really cold days, or add supplemental heat to the incoming indoor air. In the shoulder seasons you can heat/cool/dehumidify as required and keep/reject the heat as desired. There are heat pump based HRVs already available, but these need to run a compressor to do energy capture. Adding a refrigeration circuit to a conventional ERV would give so much flexibility AND some heating/cooling capacity.

[@HomePerformance]

Sounds like your new project speeder

[@superspeeder]

@@HomePerformance Corbet you have no idea how tempted I am... I work 15 minutes from the Minotair folks and I have so far resisted the temptation to drive over there and be "that guy" who knows better and asks for something they don't make! LOL

[@JeffCrawfordInTokyo]

I agree with this line of reasoning. Why can't we have an All-In-One unit that does ERV/DeHum/AC/Heating?

[@superspeeder]

@@JeffCrawfordInTokyo the Minotair does that, but it doesn’t have an ERV core so it needs to constantly run its compressor to recover heat. Because it has no enthalpy core it can’t recover humidity either, so it will dry out a building in the winter.

[@dehutech1072]

We have such unit to do the heat ing/cooling/dehumidification/Ventilation in one system!Our clients love it!

[@sepertude]

Tell us what filters did you pick please? Also how would you filter traffic pollution other than particles from entering the home? (NO2, Ozone and Sulfur Dioxide), are you adding CO2 sensor?

[@TD-zc4zi]

A lot of the US has air handlers in unconditioned spaces. This being built for ceiling, can it handle operating at 100f+ conditions?

[@shubinternet]

Interesting - you’re not also extracting air from the second bedroom?

[@nerikiri]

I’m in a rented apartment in Japan. Any suggestions for an Erv. Where can I find the formulas. Generally outside is 80 to 90% and 32 to 39c.

[@JeffCrawfordInTokyo]

@nerikiri There are several Japanese ERV brands. Some well known, others not so much. Mahbex Sumika as one type. But if you are in an apartment, your best bet is to get one of the split-AC systems that also provides heat in the winter. They are reasonably priced, and will perform well for an apartment.

[@db0nn3r]

Hey Corbett, thanks for making these videos. I’m learning, slowly. Living in south Florida and just spray foamed, getting ready to design new HVAC system. Just to confirm, the unit discussed in this video is an ERV and Dehumidifier combo?

[@dehutech1072]

Yes it is.FD-E is combo unit of dehumidifier and ERV.

[@PaulSage]

You’re right - we need that system here in the US