Backdraft Damper for HRV

[organometallics]

Hello all,

In the winter time, the outdoor vent of my Lifebreath RNC 155 Residential Heat Recovery Ventilator (HRV), gets stuck open with ice build up (when the temperatures are colder than -22oC) and then it stays stuck open outside. The problem with this, is that when the HRV is off (runs 25 min every hour), cold air pours in, and further when my furnace goes into recirculates air for 10 minutes, it spins the HRV motor backwards (because its off), and basically sucks in cold air from the outside. Long story short, although my HRV is balanced, I still get ice-build in the core up in the winter when the temperature is colder than -22oC.

I just recently purchased a back-draft damper that I would like to install myself.

It the Fantech RSK-6.

https://shop.fantech.net/en-CA/rsk--6--backdraft--damper/p139140

and I was thinking of installing it right near the collar of HRV exhaust, removing the outer pipe (the 90o pipe), installing the damper, and then placing the 90o pipe right at damper.



Assuming I install the damper correctly with the right flow...see any issues with this?


   

[scarey8]

Just install an actual 6" exhaust hood on the exterior of the house.  My thoughts are the installer used two intake hoods rather than an exhaust hood with louvers that open with duct pressure and close during the off cycle or loss of duct pressure.  would be a much cheaper cost than buying a fan tech product

[organometallics]

My only issue with this is when it's cold enough (-22oC),  ice will build up no matter. The it simply won't close all the way.

Hence having inside would help.

Just install an actual 6" exhaust hood on the exterior of the house.  My thoughts are the installer used two intake hoods rather than an exhaust hood with louvers that open with duct pressure and close during the off cycle or loss of duct pressure.  would be a much cheaper cost than buying a fan tech product