Why do you need an Energy Recovery Ventilator (ERV)? Because when you exhaust air out of the house, you need to bring more air back into the house. In warmer climates, you need an ERV, as opposed to a Heat Recovery VentilatorIn the humid climate of Central Texas, an ERV brings some humidity in the house, so Panasonic's Whisper Comfort FV-04VE1 draws about 36% of the incoming humidity into the exhaust air. It's not perfect, but that is a good chunk of humidity that won't enter the home.What else do you need to know about this specific product? It's not a small unit, and it needs to be accessible; you will have to change the filter fairly regularly. What else do you need to know about this product? Tune into the video to find out more!