Selected to configure 2nd heat/cool stage
For Two Stage Heat/Cool Systems:
Go to ADVANCED SYSTEMS SETTINGS menu.
From the Setup menu screen, press and hold the Fan and Down arrow buttons for 5 seconds. Use the Down arrow button to select the following:
2ND STAGE HEAT ENABLE: Enable second stage heating output If a single stage heating system, leave this set to N
If a 2 stage heating system, set to Y to enable.
2ND STAGE COOL ENABLE: Enable second stage cooling output
If a single stage cooling system, leave this set to N. If a two stage cooling system, set to Y to enable.