Do not use a wire that is labeled C-X-B. Wrap the wire with electrical tape. Tuck the wire neatly into the opening of the wall to which the device is attached. If your model has a heat pump, do not connect both the O and B wires. Connect only the O wire, and wrap the B wire with electrical tape. Tuck the wire into the opening of the wall.
Use the screwdriver to loosen each individual screw that is blocking access to each terminal. If you plan to use both the R and Rc terminals, disconnect the metal jumper that connects the two terminals together.
To connect each wire, insert it into the slot that exists within each terminal. Tighten the terminal screw once the wire is secured within the terminal. Tuck excess wires into the opening in the wall. Connect Rc, O and B to the terminals that feature the same labels. Connect the R-RH-4-V wire to the R terminal, the G-F wire to the G terminal, the W-W1-H wire to the W terminal and the Y-Y1-M wire to the Y terminal. If you have two wires, connect the wires to the R and W terminals.