Honeywell CT2800 Owner's Manual - Page 4

Step 2. Remove Old Thermostat Fig. 2. a. b. c. d. Turn off power to the heating/cooling system, either at the furnace or at the fuse/circuit breaker panel. Remove the cover of your old thermostat (Fig. 2). Unscrew and remove the old thermostat's mounting plate from the wall, but do not disconnect the wires. Inspect old thermostat wiring. If wiring meets any of the following conditions, see special wiring instructions section after Step 7. Fig. 3. Fig. 4. M20140 M19086 WIRES THROUGH WALL OPENING • The old thermostat is a clock thermostat with wires attached to the C or C1 terminals. • The old thermostat has six or more wires, excluding wires attached to C or C1 terminals. • The old thermostat has three wires. • There are five wires connected to the old thermostat. • There are extra wires that are not connected to the old thermostat. e. Using enclosed labels, mark wires with letter of terminal it is attached to on the old thermostat (Fig. 3). Do not label using colors. If labels do not match letters on old thermostat terminals, see wiring cross reference table in Special Wiring Instructions section. f. Disconnect the wires from the old thermostat and wrap the wires around a pencil to keep them from falling back into the wall. NOTE: Remember, if your old thermostat contains mercury, you must recycle it. See Mercury Notice for more recycling information. M20133 ✓Check your progress Your wall should now look like Fig. 4. 69-1638-1 4