An ERV (Energy Recovery Ventilator) provides fresh air to the house, with very little loss of heating or cooling energy.
Basically, it captures the heat (or cool) from the exhaust air, and uses it to condition the incoming fresh air.
An HRV (Heat Recovery Ventilator) stops at this point. An ERV goes one step further and captures the moisture in the air also.
In Oregon, an HRV is all that is needed, but this particular unit is such a good bargain for its performance, that we got the humidity recovery as well. It will be interesting to me to see if this is indeed useful or not for our climate.
Our unit, the UltimateAir 200DX, is 96% efficient at transferring the conditioned energy to the incoming air. Pretty darn good. Made in USA, too.
As we create tight, energy efficient buildings, we seal out all the unwanted air leakage that used to be unavoidable in older construction. But humans need fresh air. So we introduce the fresh air in a controlled and energy efficient way, and get both the fresh air and high thermal performance.
|Locating the Grilles
The picture above shows one way that I tried to communicate clearly what the expectations are.