Most quiet HRV on the market?
Brad Walker| Posted inMechanicalson
I’m curious if anyone can comment on noise levels of different HRV units. I’m interested in installing a CERV2 in my new house build for its air quality features but I’ve noticed the CERV1 in another house is a bit loader than I would like. Additionally, how much of the noise is due to the ducting? The decibel level doesn’t seem to be a specification that HRV companies provide.
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Replies
Noise of the unit is 90% duct work and the rest is the unit.
For the actual unit, look for something an ECM blower. These tend to be quieter.
On the noise front, you can install in-line silencers or a length of flex duct before the register. The in line silencers work extremely well but do take up space as it needs at least a 2x6 wall cavity.
We have a Zehnder Comfoair 200 hrv. It's hung from the ceiling in our mechanical/ laundry room. If you stand in the open doorway, about 8' from the unit, you can hear it. It's about as loud as a refrigerator. In the rest of the house, it's inaudble.
There is absolutely zero noise from air coming from the ducts.
The CERV has a heat pump inside it. I've never seen it in person, but that's probably the main source of noise. I spec Zehnders usually, with their manifold-silencer box, and they're very quiet especially on low & medium speeds (high for boost during showers/etc only). Properly designed (low air speed) and installed ductwork (air tight, clean connections) should not be a source of noise.
I've got a Broan HRV80S and it's silent on low speed at the ducts (2 x 4 inch round). I had to tape a piece of yarn on the ducts so I can see if it's on. You can just hear the fan on the unit, but it needs to be pretty quiet around just to hear it from a foot or two.