Honeywell T4 Pro User Manual page 8

System operation settings
● Press the Mode button to cycle to the next available System mode.
● Cycle through the modes until the required System mode is displayed and leave it to activate.
NOTE: Available System modes vary by model and system settings.
● System modes:
○ Auto
○ Heat
○ Cool
○ Off
○ Em. Heat (TH4210U only)