ERV vs. HRV - What's the Difference?

[@scottburton414]

I wish I had the information in this video three years ago when the heating contractor recommended an HRV for our Ottawa bungalow renovation. As it is, we only run it through the winter season but, according to our CO2 detector, it's keeping the inside air comfortable and fresh!

[@m00ndog3]

This is a good video! Kudos man, you made it easy to understand and explained the whys behind it.👍

[@Theconsciousbuilder]

Thanks Brandon, glad it was helpful!

[@chrishouse5753]

Cheers. Also near Ottawa - thinking of installing a heatpump to pump warm (or cool) air into the ERV and ducting the whole house (there is nothing right now - just a wood stove) - do I plan runs (with smaller ducting) the same way you think about a forced air system?

[@eduardopuit286]

Is a drain for the ERV necesarry?

[@Theconsciousbuilder]

Yes, there will be condensation that will need to drain somewhere.

[@Pharaoo2012]

Thank you for your clear and useful video, my ERV was installed by the builder with many elbows, instead off going straight to the out, just created at least 2 elbows, Are there any requirements for the number of these elbows for the in/out of the house duct, the installer maintains a specific distance from the in/ out air to be sure the in-air won't mix with the out air? if this is the reason, what is the minimum distance between both holes?

[@Theconsciousbuilder]

Hi Ralf, thanks for watching, glad it was helpful! Usually these details are all addressed in the installation instructions for the ERV. The number I have in my head is to have at least 6' between the exhaust and the intake on the exterior of the building but you'll want to double check that with the manufacturer.

[@nicholridge4797]

Great video, my questions is in a dryer climate likecthe Rocky Mountains or the western prairies would you opt for the HRV. I live in Invermere in a almost passive house with an Hrv and find it extremely dry in the winter. Im building a new passive house for myself and want to solve the issue of lack humidity any thoughts ? thank you

[@Theconsciousbuilder]

Hi Colin! I would suggest an ERV so that you can keep some of the humidity that you create while living in the house. Keep in mind that you may still need to add humidity. Depending on the size of the house and how much humidity is created by the people living in it, you may need to add a humidifier.

[@nicholridge4797]

@@Theconsciousbuilder Great to know thank you !

[@guydude4571]

What about relatively warm humid winters? Considering which to use in milder Vancouver island climate.

[@Theconsciousbuilder]

Hi Guy! If you want the Relative Humidity% from the exterior to change the RH% on the interior throughout the entire year, then you can stick with an HRV. Otherwise you'll want to use an ERV. Thanks for watching!

[@stavrosTX]

I think you answered at the very end, but could you expand on it... why wouldn't you just use an ERV most everywhere, is it cost or are there specific things and ERV can't handle?

[@Theconsciousbuilder]

Thanks for the comment Steve! I don't see an issue running an ERV everywhere but they are more expensive so it would only be a cost factor in my mind.

[@queenofpoutine]

So for central Alberta new build I should be looking at ERV, correct?

[@Theconsciousbuilder]

I would speak to an energy advisor in your climate, but if you have lots of humidity in the summer, then yes an ERV is a good idea. If you don’t then you could probably use an HRV.

[@ttoronto]

Thank you for the information. Could you please explain how to set the ventilator controller for the ERV to manage humidity levels in Toronto during both winter and summer?

[@rasras4749]

Well explained pal

[@larryseibold4287]

I am curious about your thoughts of operation during the frequent corner conditions that we experience here in the San Jose CA area, primarily spring and fall, but also in the summer from about 7pm until about 10 am where the outside temperature is cooler than the inside during cooling season. Humidity is not an issue. I frequently do not run the AC at all during this time, but need fresh air. If there is a breeze at 7pm, I open a couple of windows and all is good, but that is not a reliable thing and it is not filtered. What is the secret sauce in our area for minimal AC operation with maximal comfort? I assume that n HRV is a better choice (cost and air flow) than an ERV in this benign area?

[@Theconsciousbuilder]

Thanks for watching Larry! If you don't have high humidity in your area, then yes, I would say that an HRV can work and can run 24/7 so that you always have fresh air coming into your home. The A/C does not bring fresh air into your home.

[@mrb552]

​@@TheconsciousbuilderIs the HRV or ERV temperature configured to shut off at a certain indoor temperature if the outdoor temps drop too low?

[@SodeghRad]

I’m in Nova Scotia where summers are extremely humid (80-90% is not uncommon) and the winters are very dry. I have lots of musical instruments that need to have perfect humidity and I can’t keep up with the manual maintenance so I’d rather make the air right. Should I get the ERV and run it all year round? Does it average out the humidity in the summer AND winter to a moderate level?

[@Theconsciousbuilder]

Yes, I would recommend an ERV but note that it's not something that controls humidity. It does allows the transfer from one side of the core to the other so not all the humidity is leaving the house in the winter or coming into the home in the summer. You may also need to add a humidifer in the winter and run the A/C in the summer. Ultimately, the ERV gives you better indoor air quality but the other systems help more with humidity.

[@jeremiahdeering9645]

Ok bro, 3:23, how on earth is the MOISTURE going to transfer from incoming air to out going air? The moisture is going to magically transfer through the solid walls of the ERV?

[@Theconsciousbuilder]

The walls of an ERV are not "solid" like an HRV. An ERV transfers moisture between the indoor and outdoor air streams through a thin, paper-like membrane within its core. This membrane, which I have also read is called an exchange capillary core, allows humidity to move from one air stream to another.

[@KTS261]

We live in Ottawa and our indoor humidity in winter is always around 46% and we have problems with heavy moisture on the inside of our windows. I have been recommended an HRV to help lower indoor humidity, but only to run it in winter. Does this seem reasonable? A whole house dehumidifier is also possible, but i like that the HRV brings in fresh air to manage radon and CO2 buildup, among other things

[@Theconsciousbuilder]

You do not want an HRV in our climate. You want an ERV so that you can run it 24/7/365. HRVs can't run in the summer because of the humidity outside which defeats the purpose. You want fresh air all year round. 46% is not too high for humidity in terms of health but it is too high for condensation on windows if you do not have triple glazed windows. I would recommend changing your windows and adding an ERV. We can help if you like :)

[@JordieG8]

I recently switched from an HRV to and ERV. I’m on Vancouver Island and we have mild summers with middle of the road humidity and the winters are generally humid and mild as far as Canada goes. I found the HRV dried the air out way too much in the winter due to the massive drop in RH once that humid cool outdoor air was brought in and warmed up. Sometimes on cooler days the indoor RH was drop well below 30%. I’m hoping with the ERV I can retain a bit of the indoor humidity in the winter and will only need minor supplemental humidification. The average summer day generally maintains a nice indoor humidity level of between 45-55%. So far this fall I’ve noticed a higher average indoor humidity level with the ERV, but I just run a touch of supplemental dehumidification to get it back where it needs to be. Ultimately with the advancements made in ERV tech and defrost, they’re generally the better option in all but the most extreme climates.

[@BloominOnion1]

you should see marginal improvement with your winter conditions. The advantages of ERV are more pronounced in summer, tho

[@JordieG8]

@@BloominOnion1 the results have been better than marginal would say. It’ll still dip between high humidity activity but it takes longer for it to drop, so on average it’s been higher. Also, are humidity is pretty comfortable here in the summer. Given an average day, the indoor humidity tends to average around 45-50% resting. It’ll bump up a bit after high humidity activity and down a bit lower after an AC cycle.

[@cv2842]

Thanks, I live in southeast Wisconsin and it is hard to fond a company who knows what they are talking about. I have a home with Radiant heat and it accumulates tvoc and co2 easily. Any recomendations are appreciated

[@Theconsciousbuilder]

You will definitely want to install an ERV or HRV. I'm not familiar with your cimate but if you have hot, humid summers then you'll want the ERV.

[@insight2536]

Hi. There, I’m I am building a custom two story home located in Arizona. Should I install an HRV or ERV? And what hvac system would work best with the HRV or ERV?

[@Theconsciousbuilder]

I would suggest an ERV so that you can keep some of the humidity that you create while living in the house when it's hot and dry. Depending on the size of the house and how much humidity is created by the people living in it, you may want to add a humidifier. An ERV also helps prevent humidity getting too high if it gets very humid outside as some areas there apparently can. All that said, I'd speak to your local HVAC specialist as I'm sure they have great insight into what words best in your region.

[@MatthewKrieger]

Can you please elaborate on the booster switch option? Are those systems known by another name? You indicated that the purpose is to balance inside air needs with compensating air-intake.

[@Theconsciousbuilder]

The booster switch should be installed in every house that has an ERV or HRV. Typically they are installed in the bathrooms and will have a timer that runs for 20 minutes, 40 minutes or 60 minutes. Yes, you'll want to make sure the system is balanced properly. Ideally you have the same amount of air coming into the house as is leaving the house. Your HVAC contractor should be able to do this and the HVAC design should have the required CFM for each room.

[@MatthewKrieger]

@@Theconsciousbuilder Thank you. But the booster switch itself - is it a "switch" or is a damper with a fan? I am unclear about the terminology and don't get a lot when I Google it. Is there an alternative name?

[@richdobbs6595]

What about radiant heating or mini split heat pump conditioned homes? Are there ERV's that are designed to be installed for a room or two? This will be an off grid home that will be built in phases.

[@Theconsciousbuilder]

Yes, there are smaller ERVs now on the market and even single room ERVs. We have not used the single room ERVs yet so talk with a local HVAC contractor to see if they have experience.

[@Itsme-vo4fx]

I have an older HRV and live in the Toronto area. Can I simply replace it with an ERV, using the same ductwork that is there now? (The HRV is presently attached to the furnace)

[@Theconsciousbuilder]

It may be possible to switch them out however I would speak with an HVAC specialist about your particular setup to be sure of models and system compatibility.

[@jena1307]

Hi, thanks for the great video! I live in Yarmouth NS, which is actually not a humid place compared to Ottawa where I used to live. Would you recommend an HRV or an ERV? I should mention that my home is a 1960s bungalow with electric baseboard heating only. The existing HRV was an old NuTone heat air exchanger so there is existing flexible ductwork in the attic that connects to ceiling vents in several rooms in the house. The VanEE AI Series (HRV) Model V160H75RT was recommended to me as it is self balancing and I plan to do the install myself given the existing ductwork - although the electrical will likely need a professional as the new controllers have 4 wires and the existing only has 2. Appreciate any advice or considerations! Thank you!

[@Theconsciousbuilder]

If there's no concern with maintaining a different humidity level inside compared to outside, then an HRV would work. If you need the humidity in the house to be different from the outside air, I would recommend an ERV. I would also recommend you have an HVAC designer help you design the system and make sure the existing ducts will work for you.

[@akoyoat]

this is a great explanation. what's your favorite all round erv make and model?

[@Theconsciousbuilder]

Hey, glad it was helpful! I usually rely on the expertise of our HVAC contractor but it also depends on what the requirements are for the project with regards to efficiency. Ultimately, I lean towards systems that are well known by contractors and systems that have parts readily available. It's a real pain dealing with systems that have minimal service techs and that are hard to get parts for.

[@perodeau669]

Thanks for the great video. I need an advice regarding control problem of HRV 60H in my condo unit. When I tried to tun off power using wall mount control but it didn’t work. Therefore the ventilator is running 24/7 unless I pull the plug off. Can you help to resolve this problem? I live in Montreal.

[@Theconsciousbuilder]

Hi Perodeau, you should reach out to a local HVAC tech in your area. Unfortunately without being there its hard to say what's happening. Thanks for watching!

[@perodeau669]

@@Theconsciousbuilder Thanks very much

[@jko0526]

Everybody has these videos telling us the difference between the HRV and ERV but no one mentions what you should do if you have an HRV that was installed in a house that you bought but still want to use it in other seasons besides winter. I don’t have the budget to install a pricey new unit.

[@Theconsciousbuilder]

The HRV is better than nothing. You can run it throughout the majority of the year but you may not want to run it in the summer if you live somewhere with a lot of humidity.

[@youtubewts]

What about in the UK?

[@Theconsciousbuilder]

Thanks for watching! If you're unsure which is best in your region I suggest speaking with a local HVAC installer.

[@youtubewts]

@@Theconsciousbuilder 🤦 Helpful

[@julianpatterson3944]

I'm in Toronto , would an ERV be best? I see comments that say ERV dries out the house would I need to add a humidifier as well ?

[@Theconsciousbuilder]

An ERV will allow you to keep some of the humidity that you create while living in the house. You may still need to add humidity. Depending on the size of the house and how much humidity is created by the people living in it, you may need to add a humidifier.

[@tharindujayasekara237]

Can we control humidity with both HRV and ERV in winter?

[@Theconsciousbuilder]

If you want the RH% from the exterior to change the RH% on the interior throughout the entire year, then you can stick with an HRV. Otherwise you'll want to use an ERV.

[@eh4172]

I'm in Ottawa too and in the market for an ERV. Who would you recommend?

[@Theconsciousbuilder]

Shoot us an email with more details about what you're looking for and we'll guide you to the right person! [e-mail]

[@kitsurubami]

Awesome thank you!

[@Theconsciousbuilder]

Thanks for watching!

[@larry9441]

Pollen can be filtered out and the house pressurized just enough to send air out through cracks and around doors and windows also. This is helpful to allergy sufferers. Good topic Cassey.

[@Theconsciousbuilder]

Thanks Larry!

[@eliinthewolverinestate6729]

We sub out hvac. I don't pay much attention. I found out I need hrv hooked to "vent to daylight" on my personal cottage build. So will need to dig a pit for it. And an erv on 20 foot tall south wall over planter and plants. I had to get exhaust fan for my boiler and hot water for my old house. After installing vapor barriers and mineral wool. Our hvac guy is like that's the first he does is make an air inlet for regular build. With us he never knows wtf we got going. Usually some kind of radiant heat, with backup/supplemental efficient masonry appliances. Which people are surprised how much ventilation a fireplace needs. Which is why we try to avoid forced air with gas and wood appliances. Don't vent your stove hood into hrv the grease will clog it.

[@virgil3241]

Difference between the 2 are, no matter which one you pick, a whole bunch of people will die on a hill telling you how wrong you are. But this explains both well.

[@Theconsciousbuilder]

It really is about what works best for your specific climate and needs. Thanks for watching!🙂

[@virgil3241]

@@Theconsciousbuilder I agree. Its a shame some people dont want to listen to that logic

[@makkavelli3972]

My house is really air tight and very dry air to the point that plants die,,,which one should i get???

[@Theconsciousbuilder]

Where do you live? Sounds like you may also need a humidifier.

[@makkavelli3972]

@@Theconsciousbuilder in The City in the UK,,,the house was an old house re renevated by the council the put new cladding front and back and new roofs,,but made it soo air tight you can hardly breeth,,,always wake up with a dry mouth and bad sleep,,i tried a Himidifiier but the bedroom is soo large and ceilings soo high they never work.. Its a nightmare

[@davesiringo7147]

Thanks for the video. Question: are ERVs compatible with heat pump/a/c systems as I live in the southeast?

[@Theconsciousbuilder]

Yes, make sure you speak with a local HVAC professional to ensure compatibility with the units you use!

[@TinMan-HVAC]

If you have an ECM blower fan, you SHOULD run you furnace fan 24/7

[@smirkinatu5512]

Why do HVAC companies in the United States seem to make this more confusing, or it beyond what I (layman) can comprehend. i.e. leave it to the pros? My guess is $$$$. What say you?

[@Horse-c2t]

You lost me 15 seconds in

[@Theconsciousbuilder]

Can't win em all

[@mamishami9820]

At least I am not bothering neighbours with buzzing and low frequency noise 24/7 that has completely ruined my peace and quiet.

[@excictinceispointless]

Kind of funny hrvs have a condensate drain e RVs do not. Have you ever actually looked at these units are you just regurgitating

[@MichaelJ674]

Ignorant troll comment…