How do I access the installer setup (ISU) on my TH4210U2002, TH4110U2005 thermostat?
1 Press and hold Menu and + buttons for approximately 5 seconds to enter advanced menu.
2 Press Select to enter System Setup (ISU) menu.
3 Press Select to cycle through System Setup numbers.
4 Press + or - to change values or select from available options.
5 Press Select to save changes and advance to the next System Setup number.
6 Once you have cycled through all of the System Setup numbers, “Done"" is displayed. Press Select to save and exit. To save and exit early, press Home to return to the Home screen.