RemoTec ZXT-120 Configuration

From Universal Devices, Inc. Wiki
  1. Configure parameter 27 to set up code 0
  2. Configure parameter 25 and value from 0-22 to learn specific IR code data from your original remote control
  3. After the IR code is learned, then go back to thermostat control page

For the details, please refer to page 9-12 of user manual.