Heat Recovery Ventilator Calculator

Size HRV/ERV units and calculate energy recovery performance.

Ventilation Requirements

Design Conditions - Heating

Design Conditions - Cooling

Recovery Efficiency

HRV vs ERV Selection

ClimateRecommendedWhy
Cold & DryERVRetains moisture
Cold & HumidHRVRemoves excess moisture
Hot & HumidERVRemoves latent load
Hot & DryHRV/ERVEither works

Typical Efficiencies

HRV: 70-80% sensible, 0% latent

ERV: 70-80% sensible, 50-70% latent

ASHRAE 62: Minimum 50% sensible recovery