From inside (document excerpt):
25HCB6 Comfortt Series 2 Stage Heat Pump with Puronr Refrigerant 2 To 5 Nominal Tons Wiring Diagrams CONNECTION DIAGRAM. THIS DEFROST CONTROL BOARD CONTAINS A FIVE MINUTE SHORT CYCLE PROTECTOR.
A FIVE MINUTE DELAY WILL OCCUR BETWEEN COMPRESSOR OFF/ON CYCLES. OF2 120 START CAPACITOR *SC START RELAY *SR START THERMISTOR *ST *UTS UNLOADER TEMP SWITCH * MAY BE FACTORY OR FIELD INSTALLED 335977-101 REV. A -LEGEND- Fig. 1 Wiring Diagram — Model sizes 2- tons, 208/230-5 -1 2009 Carrier Corp. S 7310 W. Morris St. S Indianapolis, IN 46231 Printed in U.S.A. Edition Date: 09/09 Catalog No: 25HCB6 1W Replaces: New Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations