Aprialire #56 OEM Auto-Trac Control System Humidistat
Aprilaire Model 56 automatic humidistat designed for low voltage (24v) humidifier control. Computer-equipped, completely automated, never needs manual adjustments. The advanced computer technology measures the outdoor temperature and indoor humidity and continually adjusts your homes indoor humidity to its optimum level.
Includes humidistat, outdoor temperature sensor with 36 inch wire and bracket, manual mode resistor. For Upflow or Horizontal furnaces.