COMMON TERMS AND WHERE TO FIND THEMAuto changeover .................................... page 36This feature automatically switches your system from heating to cooling - or fromcooling to heating - whenever necessary when in auto mode only (heat/cool).Auxiliary heat (heat pump systems and Hybrid Heat systems only)page 25Most heat pump systems can't heat a home sufficiently when it gets very coldoutside so they use a supplemental heating source called auxiliary heat. The systemknows when to use this help and does so automatically. If it's using auxiliary heat,the display will show aux heat on when you press the mode button. You have nocontrol over the auxiliary heat function.BacMighting ........................................ page 31Backlighting illuminates your display. The backlight is on constantly at a dim levelthat brightens when you push a button.Dehumidify ........................................ page 21When your heating and cooling system is used to dehumidify the air and thethermostat is set up to dehumidify, the thermostat will instruct it to remove moisturefrom the air as necessary when the air conditioning is on.