[mrspuratic]

A perfect ERV will recover the heat (occurs naturally by a temperature difference) and the latent heat (associated with condensation/evaporation). i.e. water vapour in the outbound flow should be transferred the inbound flow.

This is to avoid energy loss that would occur when moisture condenses (i.e. the latent heat) by using an adsorbant material to capture moisture before it escapes, or a membrane that allows moisture in the outbound flow to pass to the inbound flow.