I have a few questions... If an ERV conditions fresh air based of transfer of moisture and energy from inside air, would it not be then bad to pull hot humid air from a shower and transfer its energy to air that gets dumped into the room? Ive heard of people using ERVs as their exhaust in a bathroom, is this your plan? Also are you planning to put a dehumidifier as well? Thanks for all you do in making homes better!
We live in an area with heavy wildfire smoke in the summer and fall (Central Oregon). Is there an ERV that you know of that is highly efficient with built in HEPA filtration?
Aiden, unless your home is very airtight I don’t think an ERV would be the right solution (and no, I don’t know of any with HEPA filtration). You could look at the Fantech CM3000 which would just pull air from outdoors into your home, pressurizing it slightly. If you need consulting to fully understand your options, I’m available at: buildingperformanceworkshop.com/video-consulting
Hello, What sensors might be employed to “monitor the quality of air”? What elements of air quality might be monitored and measured? Upon determining the various elements that determine the quality of air in real time. Would you employ a logic controller to adjust the dampers per ever changing quality of air permanents, or manually adjust?
I might be misunderstanding but the biggest piece of this puzzle is how to get rid of the human element of constantly adjusting, turning fan speeds up, down, HEPA on off, pressure balancing, etc ... Do I have to constantly juggle these things on a daily basis or is there a computer monitoring system checking the air doing it for me?
good stuff - thanks. When you spoke about damping down the two systems you stated that it would be according to your monitoring the air quality. How is the space monitored?
what happen to all those conditioned spaces (attic and crawl space) when there is long term power outage (or say you just want to turn off the AC and open some windows)? Anyone know the long term effects in such situation? I keep thinking about converting to conditioned spaces but I don't think that works unless you have some mechanicals running all the time.
Houses nowadays are so airtight that no matter what, if you have a long term power outage, you're in trouble. A mall in Malaysia has been closed for a month due to COVID abandonment, with the A/C off, and everything in every store is covered in mold now. We can't do our civilization without machines today.
At least where I live, power outages are a real concern. As for the crawl space, it shouldn't be too hard to utilize some sort of closeable/pluggable vents that seal airtight when the hvac is active, but allow natural ventilation when needed. Another concern is having a heat source powerful enough to heat your now not-so-airtight house. I therefore find a fuel/wood burning heater necessary even if a small heat pump suffices normally.
Why are you insulating the exhaust duct of the erv? Since an erv is less than 100% efficient, you'd get additional heat transfer before the stale air leaves the envelope if you leave the exhaust duct uninsulated. Similarly, if you leave the intake uninsulated, the crawl space will precondition the fresh air before the erv and the air gets blown into the occupied space. Am I missing something?
Hi HP. I've watched enough of your content to know that you have extensive knowledge of home IAQ. I'm looking into ERVs and found the CERV2. It sounds like precisely what I want (ERV with sensors and software that controls all aspects of IAQ automatically). But, the company is very small and I'm hard pressed to find any reviews or user stories about it. Are you familiar, can you share your opinion of this "smart ventilation" system, or if there are any others that automate our goal of healthy home air? Thanks so much, Tim.
Hey Tim- you’re right, it’s been filling a niche until now. My friend Bill Spohn, owner of TruTech Tools has a CERV installed in his new home, but he hasn’t posted any formal reviews yet. My issue with it, along with Zehnder systems, is that it’s so massive. Broan bought an ERV maker a dozen years ago called Venmar, and they’ve been doing really cool things over there. They have a new ERV called the AI series that connects to Overture, basically the conductor for all fans in a home (or as many as you want to connect). Check that out here: www.broan-nutone.com/en-us/overture Best of luck with your home!
Hi Corbett, congrats on the new baby! i'm looking for the video where you flashed your ERV ducts to your WRB on the outside. Do you remember which video that was? Thanks!
Will be interesting to see your ducting set ups in this house. Lots of people try and toot there own horn and talk about face velocity and the k factor on the grilles. Then they fail to even turn a elbow to the right geometry or set the correct blower speed on the unit. It’s important to get the basics right and sorted out first. Are you going to utilize a mini ducted system on your house or just sticking with ductless?
I think it's possible to have the ERV intake stream tie into the HEPA intake stream. That way all outdoor air passes through the HEPA before entering return duct. But since the CFM of the ERV is lower than the CFM of HEPA, this configuration will require an additional takeoff and return duct off the main return trunk and a Y to connect ERV intake to additional return duct before connecting to inlet of HEPA.
@@HomePerformance , then you'll potentially have VOCs, allergens, other toxic particles enter your house through the ERV. Or you can get a MERV 13 filter for your ERV but why if you already have a whole house HEPA cleaner.
If you live someplace where there are toxic or stinky substances outside, then sure- but s HEPA filter does not catch smells (VOCs). A carbon filter does that.
Why did you use a mini split instead of forced air heat and ac? you have all the ducts you need for the ERV / Hepa. I did a consult with you and recommended that I don't use ductless mini-splits, yet you decided to use one in your house.
@@HomePerformance That makes so much sense. Plus, if it was part of an furnace / AC duct system, it would only run / ventilate was the furnace heat or AC was running, correct?
Thanks Steven, but the 3/4 ton minisplit is oversized. Actual load with 2 people is 4,000 Btuh- we modeled heat load with 15 ppl and came up with 8,000. The two fans in there blow 10,000 CFM each. Not worried about making people comfy while partying!
@@HomePerformance See that's the actual science you need to go into. Cover the load calculations for sensible and latent heat accounting for losses in pipe diameter, why you use longer sweep elbow's etc. Then later measure to see if the model was correct. Sadly that content will bore most users and hurt your click count.
I have a few questions... If an ERV conditions fresh air based of transfer of moisture and energy from inside air, would it not be then bad to pull hot humid air from a shower and transfer its energy to air that gets dumped into the room? Ive heard of people using ERVs as their exhaust in a bathroom, is this your plan? Also are you planning to put a dehumidifier as well? Thanks for all you do in making homes better!
Love that use the commercial size HEPA filters in residential last forever with a good pre-filter
Thanks a lot. Pure gold
We live in an area with heavy wildfire smoke in the summer and fall (Central Oregon). Is there an ERV that you know of that is highly efficient with built in HEPA filtration?
Aiden, unless your home is very airtight I don’t think an ERV would be the right solution (and no, I don’t know of any with HEPA filtration). You could look at the Fantech CM3000 which would just pull air from outdoors into your home, pressurizing it slightly. If you need consulting to fully understand your options, I’m available at:
buildingperformanceworkshop.com/video-consulting
kick ass. remember those plumbing cleanouts i keep mentioning.
Hello,
What sensors might be employed to “monitor the quality of air”?
What elements of air quality might be monitored and measured?
Upon determining the various elements that determine the quality of air in real time. Would you employ a logic controller to adjust the dampers per ever changing quality of air permanents, or manually adjust?
I might be misunderstanding but the biggest piece of this puzzle is how to get rid of the human element of constantly adjusting, turning fan speeds up, down, HEPA on off, pressure balancing, etc ... Do I have to constantly juggle these things on a daily basis or is there a computer monitoring system checking the air doing it for me?
Yes, you are 100% right. Stay tuned, there are some brand new innovative control systems we’ll be installing that you can use in any home.
That is a nice crawlspace. How tall is it?
4 ft to underside of joists
good stuff - thanks. When you spoke about damping down the two systems you stated that it would be according to your monitoring the air quality. How is the space monitored?
We'll have a variety of monitoring instruments, including Fantech's own system, CPS SmartAir station, TZOA, etc.
@@HomePerformance will you be featuring this monitoring and review the results after you've moved in?
Of course
what happen to all those conditioned spaces (attic and crawl space) when there is long term power outage (or say you just want to turn off the AC and open some windows)? Anyone know the long term effects in such situation? I keep thinking about converting to conditioned spaces but I don't think that works unless you have some mechanicals running all the time.
Houses nowadays are so airtight that no matter what, if you have a long term power outage, you're in trouble. A mall in Malaysia has been closed for a month due to COVID abandonment, with the A/C off, and everything in every store is covered in mold now. We can't do our civilization without machines today.
At least where I live, power outages are a real concern. As for the crawl space, it shouldn't be too hard to utilize some sort of closeable/pluggable vents that seal airtight when the hvac is active, but allow natural ventilation when needed. Another concern is having a heat source powerful enough to heat your now not-so-airtight house. I therefore find a fuel/wood burning heater necessary even if a small heat pump suffices normally.
Why are you insulating the exhaust duct of the erv? Since an erv is less than 100% efficient, you'd get additional heat transfer before the stale air leaves the envelope if you leave the exhaust duct uninsulated. Similarly, if you leave the intake uninsulated, the crawl space will precondition the fresh air before the erv and the air gets blown into the occupied space. Am I missing something?
Condensation. Energy recovery is nice, but if it's 30 degrees outside, you'll have the outside of both outward-facing ducts soaking wet.
Hi HP. I've watched enough of your content to know that you have extensive knowledge of home IAQ. I'm looking into ERVs and found the CERV2. It sounds like precisely what I want (ERV with sensors and software that controls all aspects of IAQ automatically). But, the company is very small and I'm hard pressed to find any reviews or user stories about it. Are you familiar, can you share your opinion of this "smart ventilation" system, or if there are any others that automate our goal of healthy home air? Thanks so much, Tim.
Hey Tim- you’re right, it’s been filling a niche until now. My friend Bill Spohn, owner of TruTech Tools has a CERV installed in his new home, but he hasn’t posted any formal reviews yet. My issue with it, along with Zehnder systems, is that it’s so massive.
Broan bought an ERV maker a dozen years ago called Venmar, and they’ve been doing really cool things over there. They have a new ERV called the AI series that connects to Overture, basically the conductor for all fans in a home (or as many as you want to connect). Check that out here:
www.broan-nutone.com/en-us/overture
Best of luck with your home!
Hi Corbett, congrats on the new baby! i'm looking for the video where you flashed your ERV ducts to your WRB on the outside. Do you remember which video that was? Thanks!
Thank you Cindi- here it is, at 1:50:
ua-cam.com/video/_lqr8R2i5Vo/v-deo.html
Will be interesting to see your ducting set ups in this house. Lots of people try and toot there own horn and talk about face velocity and the k factor on the grilles. Then they fail to even turn a elbow to the right geometry or set the correct blower speed on the unit. It’s important to get the basics right and sorted out first. Are you going to utilize a mini ducted system on your house or just sticking with ductless?
One of each, Ethan. I agree, it's always systems, systems.
I think it's possible to have the ERV intake stream tie into the HEPA intake stream. That way all outdoor air passes through the HEPA before entering return duct. But since the CFM of the ERV is lower than the CFM of HEPA, this configuration will require an additional takeoff and return duct off the main return trunk and a Y to connect ERV intake to additional return duct before connecting to inlet of HEPA.
That's a cool idea too, but I expect a lot more of the tiny particles I need the HEPA for to be generated inside, rather than coming in from outside.
@@HomePerformance , then you'll potentially have VOCs, allergens, other toxic particles enter your house through the ERV. Or you can get a MERV 13 filter for your ERV but why if you already have a whole house HEPA cleaner.
If you live someplace where there are toxic or stinky substances outside, then sure- but s HEPA filter does not catch smells (VOCs). A carbon filter does that.
@@HomePerformance automobiles are everywhere. Most modern whole house HEPAs are 3-stage and have optional VOC capturing carbon filters.
Right you are
Why did you use a mini split instead of forced air heat and ac? you have all the ducts you need for the ERV / Hepa. I did a consult with you and recommended that I don't use ductless mini-splits, yet you decided to use one in your house.
The ducts are not big enough to handle all of these devices at once, and they would be massively oversized most of the time if you built them bigger.
@@HomePerformance That makes so much sense. Plus, if it was part of an furnace / AC duct system, it would only run / ventilate was the furnace heat or AC was running, correct?
How do you know how many achs you need?
ASHRAE 62.2 is the standard midpoint you should aim for.
As an engineer who also dances. That system seems vastly undersized for cooling. A single minisplit won't be enough. Seen that at many studio's now.
Thanks Steven, but the 3/4 ton minisplit is oversized. Actual load with 2 people is 4,000 Btuh- we modeled heat load with 15 ppl and came up with 8,000. The two fans in there blow 10,000 CFM each. Not worried about making people comfy while partying!
@@HomePerformance See that's the actual science you need to go into. Cover the load calculations for sensible and latent heat accounting for losses in pipe diameter, why you use longer sweep elbow's etc. Then later measure to see if the model was correct.
Sadly that content will bore most users and hurt your click count.
Then you’ll be delighted to know there’s an hourlong video of that:
ua-cam.com/video/aCIrbSFWD20/v-deo.html
Corbett I’m am an audio engineer/equipment dealer, if you need any audio gear for your space I’d be happy to hook you up.
Hey Baron- thanks, please send me an email via my website:
BuildingPerformanceWorkshop.com
That Biden reference @ 6:52 LOL