If your unit has the capability of adding sensors in addition to the 5-in-1 sensor and the display is unable to connect to the additional sensor or sensors.
- Make sure that the 5-in-1 sensor is connected to the display first.
- Remove the batteries from the Temperature & Humidity Sensors.
- Verify the sensors are set to different A-B-C channels.
- Locate the A-B-C switch inside the battery compartment of each sensor.
- Verify the sensors are set to different channels from each other. If multiple sensors are on the same letter channel, move the switches so that no two sensors are on the same channel.