Heat Recovery Ventilators (HRV)
An unintended consequence of tightly sealing your home for energy efficiency purposes is that indoor generated contaminants and excessive moisture stay around a lot longer. Exhaust fans often fail to provide adequate ventilation because of the lack of “make-up” air. Besides, exhausting air and opening windows defeats the purpose of weatherizing your home.
Heat Recovery Ventilators (HRV) provide balanced ventilation, bringing in outdoor air at the same time that stale or contaminated air is exhausted. Heat energy passes through a heat transfer core, recovering 60-80% of the energy between the intake air and exhausted air. The Energy Recovery Ventilator (ERV) is a cousin to the HRV, but passes both heat energy and moisture through the transfer medium.
The HRV or ERV can be integrated into a central forced air heating (and/or cooling) system, or can be a stand alone system for homes without forced air systems. In radiantly heated homes, we typically exhaust from the bathrooms, and provide the make-up air into bedrooms or other living spaces. Outdoor air is filtered before entering the HRV/ERV and home.