The thermostat is located behind the bathroom door. When you arrive, it should be set to Auto, as indicated by the indicator on the left above the temperature (similar to a modified recycling logo). However, the temperature cannot be adjusted in Auto.
If you wish to adjust the temp, press the Mode button. Air conditioning uses a snowflake icon, and cycle to the sun icon for heat, though they look a little similar. The Up and Down buttons can now be used to set the desired temperature.