The OAS Outside Air Sensor allows precise real time monitoring of the Outside Air temperature on your Zoned HVAC system. The OAS is a versatile device because it can be mounted on an outside wall or an outside air duct. Make sure the OAS is mounted completely outside of the house, on the North, East, or West side of the building. Avoid direct sunlight. Do not mount the OAS low to the ground where snow can cover it. Do not mount the OAS close to exhaust vents of any type. Use a dedicated 2 conductor 18AWG solid copper jacketed thermostat cable to connect the OAS to the Zone Control System, Economizer or the Smart Humidistat. Avoid running cable in close proximity to line voltage circuits, or inside a conduit with other circuits. Avoid wire runs in excess of 100 ft.