| >An ERV itself does nothing for air quality I disagree — it is literally exchanging outdoor air with indoor air; so perhaps if it was heavily polluted outdoors then it could certainly worsen indoor air quality. >Setting your furnace fan to ON to increase the number of air exchanges in your house without the heat exchanger would do the same thing. I think you are misunderstanding how an ERV is plumbed. Unlike furnace `ON` cycling indoor air indoors, the ERV is literally exchanging inside/outside air constantly & entirely, directly through the plate membrane. >Your indoor air quality, assuming your HVAC is properly balanced to have positive pressure In the ERV setup I described installing, earlier, it is the ERV which generates/maintains the positive pressure differential. >There are also heat exchangers that capture latent heat from your shower water [1] to preheat the cold water line going into the hot water heater, though I am unsure if you’d ever capture enough latent heat back to pay for it. This is why instead of drain heat capture (not economical at microscale) to save energy, I installed a heat pump water heater. I live in the US SE (technically a subtropical rainforest) so the heating of the water is essentially "free cooling / dehumidifying" for all the non-HVAC-heat days of the year (~9 months). During the brief winter, it switches over to standard dual 4500W heating elements. |