The Engineering Math Behind Energy Recovery Wheels: Decoding ASHRAE Effectiveness Formulas

Energy recovery wheels can achieve up to 80% total effectiveness in ideal conditions, but that number hides complex thermodynamic interactions between temperature and humidity transfer that many engineers oversimplify. The Formula The ASHRAE effectiveness formulas for energy recovery wheels represent elegant applications of heat and mass transfer principles. The sensible effectiveness formula ε_s = |T_oa − T_sa| / |T_oa − T_ra| × 100 quantifies how efficiently the wheel transfers sensible heat b