What is the best house air ventilator

If you have a well sealed house like the Brooklyn Green Show House you need to add an air ventilator.

The best kind is one that recoups the heat and cold that leaves the house. That would be called a Heat Recovery Ventilator (HRV).

But another thing is humidity. You want it to stay within healthy levels in the house. An energy recovery ventilator (ERV) can monitor the humidity levels as well as recover heat and cold.

Even though technically ERV’s have been around for about 30 years, they are not common for small residential use and it is still hard to get good information on which one to buy.

I have looked around and found a handful. I share my research here:

Paul is a leading ERV from Germany. They have a heat recovery technique where air flows over 4 surfaces instead of two, thus making it much more effective.

American Aldes has a “vent zone” system where you can control different zones of the house, thus reducing the need for a large fan and thus saving energy.

Conservation Technology uses an exhaust only system and they claim this is more energy efficient. They combine it with occupant sensing technology so that the fan can regulate its speed based on the need.

Renew Air claims to have the most energy efficient fans in the US. They also boast quiet fans. It seems to be mostly an ERV that you hook up to an existing air circulation system that would handle heating and cooling but you can probably use it separately too.

AirScape is more of a cooling system to replace AC. It is good for running at night to cool down the house. Not really a system to help keep the heat in during the winter so it’s not actually an ERV. But it is a very effective alternative to AC cooling in the summer.

Ultimate Air claims to have one of the highest efficiency in the industry.

Lifebreath offers a good ERV.

Aprilaire only recovers 77% of the energy. Not great.

My favorites are Renew Air and Ultimate Air. I lean towards Ultimate Air because they are really into the Passive House technique of building. We are increasingly building along Passive House standards in our green contractor work on Brooklyn brownstones. It covers a lot of the energy considerations in a green renovation.

Posted in All Posts
One comment on “What is the best house air ventilator
  1. Tedd says:

    I love the RecoupAerator for larger projects in humid climates, but the 200 cfm is way overkill for more modest and cold climate houses. You would need to operate it on the lowest speed setting (70 cfm or so) to get realistic ventilation rates without excessive electrical consumption. At the 250W for 200 cfm, it does not meet the PassivHaus standards of < 0.8 W/cfm (PS when did Katrin get a PhD and become a professor?) At these low speed settings, the fans are more efficient that the specs below (eg they draw far less than 250W, which is a very high number). I have not yet had my meter on one, but given the type of motors they used (and the ubiquitous EBM Papst supplier) I would expect 50-100W (which is good to tolerable). That said it is quite expensive,in the range of $1600-1900. I also would also be careful about using an ERV in a very airtight house in a cold climate because the ventilation is needed to REMOVE humidity. In my own airtight house (under 1 ACH@50), in a 7500 HDD climate, the RH is pretty high (just over 40%RH) with an HRV core, and plans to use an ERV core were thus put on hold: and ERV would cause the RH inside to rise to dangerous and damaging levels. A Fantech SHR704 delivers 60-70 cfm and consumes less than 40W (0.65 W/cfm). This is good for modest sized houses. It costs about $450 wholesale. Given its price and performance it is one I often recommend and see recommended. Venmar has a very efficient and flexible product called the Eko 1.5 It can deliver up to 200 cfm, but is more intended for operation in the 100-150 cfm peak flow region. Operated continuously or nearly so, at low speed it draws between 25 and 35 W (yup, thats all) while move 65-75 cfm of air. Yup that is 2 cfm/Watt, well better than most products. Of course, the catch is, and the reason I dont own one, is that it costs almost as much as the RecoupAerator, that is, over $1500.

Leave a Reply

Your email address will not be published. Required fields are marked *