How do I permanently hold a temperature setting on the XL824?

To permanently override a schedule, press in the Indoor Temperature area to reveal the Temperature Control Panel and adjust your set points using the Up and Down arrows. Then select Hold Perm, and the words 'Hold Perm' will appear in bold type. The control will maintain that temperature setpoint until you manually cancel it by selecting Hold Perm again, after which the display will indicate 'Following Schedule.'