HRV systems exhaust stale air from a building and replace it with fresh outdoor air, recovering heat energy in the process. ERV systems, on the other hand, not only recover heat energy but also transfer moisture from the exhausted air to the incoming air, reducing the load on the building’s HVAC system. ERV systems also restrict moisture from entering the building, which is particularly important in humid climates. While both systems provide ventilation and heat recovery, ERV systems offer additional moisture management capabilities.