- 1). Remove the battery compartment cover on the sensor by unscrewing it using a Phillips screwdriver. Insert the appropriate batteries, typically AA or AAA, in the compartment, matching the polarity signs. Close the cover and secure it by tightening the screws. Pop off the battery compartment cover on the main unit and insert the appropriate batteries; pop the cover back on. Press "reset" after changing the batteries.
- 2). Select a channel, usually 1, 2, or 3, on the sensor and the main unit, choosing the same channel for both. Most outdoor thermometers give you the option to add sensors if needed, and each one must use a different channel. Choose the channel on the main unit to receive information from the sensor based on its channel number.
- 3). Set the sensor by the main unit and press "reset" on the sensor. At the same time, press "channel" and "mem" on the main unit to send a signal between the main unit and the sensor.
- 4). Set the sensor in its stand or mount it outside using the bracket and screws. The ideal location is under an eave so that the sensor is out of direct sunlight and protected from rain and snow. Place the main unit inside in its stand or mount it on a wall.
- 5). Switch between the settings, such as Celsius, Fahrenheit, alarm, clock, time zone and date, by pressing the buttons on the back of the main unit. Use the up and down buttons to change options once you have switched to a setting.