The variable speed EC Motor has the best efficiency and control, removes up to 4X more humidity, as well as providing the quietest option;Balanced blower wheels for smooth, vibration-free operation;Direct drive motor for improved efficiency;Shaft key connection;Separate control box;Control voltage transformer;Screw terminal connections;Heat pump AFS bypass;Boiler relay to connect a hot water heating source;Six (6) modes of operation;Adjustable low airflow mode;Efficient ventilation mode;Point-to-point wiring;Electric heater fan interlock;Electric heater stage 3 lockout protection;Chilled water relay for connecting to a chilled water source;Fan cycling EAC, ERV, or HRV relay;Potable water circulation;Humidifier compatibility;Soft-start and soft-stop for quiet operation;Constant airflow;Low airflow indicator;Preset airflow rate to maintain a given rate of airflow as needed;Laptop configurable;Laptop troubleshooting for ease of service;Optimized for zone damper systems;Optimized for efficiency and sound