Heat Recovery Ventilation (HRV) transfers thermal energy from exhaust air to incoming fresh air, recovering 50-80% of heating or cooling energy. An HRV core containing thin metal or plastic plates allows heat transfer between outgoing and incoming airstreams without mixing contaminated air with fresh air. This technology significantly reduces energy consumption in heating-dominated climates.
Technical Performance
HRV systems achieve sensible heat recovery efficiency ratings of 60-85% under ideal conditions, with actual performance varying by temperature differential and air velocity. A typical residential HRV delivers 50-100 CFM while recovering 1,500-3,000 BTU per hour in winter conditions. Counterflow core designs maximize heat transfer surface area. Regular filter replacement and core cleaning maintain efficiency, typically required every 6-12 months.
Climate Suitability
HRVs perform optimally in cold climates where heating represents the largest energy load. They provide less benefit in hot-humid regions where cooling and humidity control dominate. Moisture carryover can occur in cold climates below 0°F, requiring defrost cycles that bypass the core. HRV installation requires careful ductwork design, sealing, and maintenance to realize energy savings of 15-30% compared to standard ventilation approaches.