APOLLO Commercial Energy Recovery VentilatorAPOLLO Commercial Energy Recovery Ventilator The APOLLO Commercial Energy Recovery Ventilator (ERV) is designed to provide continuous fresh air, balanced ventilation, and improved indoor air quality while helping reduce heating and cooling energy loss. Available in multiple models AP COM ERV 150, AP COM ERV 250, AP COM ERV 350, and AP COM ERV 500 this ceiling mounted ERV can be selected based on the airflow and duct size requirements of the project.