Locate a convenient, easily accessible position on a wall to mount the battery-operated switch. Place the template included with the old-work junction box on the wall in the selected location. Trace around the template with a pencil, then remove the template.
Cut along the pencil lines with a drywall saw. Push the old-work box into the hole in the wall. Tighten the screws on the old-work box with a Phillips screwdriver.
Pull the plastic battery-insulation tab out of the side of the wall switch. Fit the switch into the old-work box, insert a one-inch #6-32 screw in each mounting hole and tighten them with a Phillips screwdriver. Place a decorator plate over the face of the switch and mount it with the included flat-head screws.
Open the back of the wireless receiver and install four "AA" batteries according to the diagram inside the battery compartment. Slide the switch on the receiver to the "Off" position.
Open the control panel on the front of the Napoleon ventless fireplace. Place the wireless receiver in an open area behind the control-panel cover.
Run a length of two-conductor wire from the wireless receiver to the fireplace switch. Strip the ends of the conductors, exposing ½ inch of bare wire.
Slide the bare ends of the conductors into the terminals on the back of the receiver. Tighten the terminal screws on the back of the receiver.
Place spade connectors on the bare conductors at the end of the two-conductor wire at the fireplace switch. Crimp the connectors onto the wires. Slide the spade connectors onto the terminals marked "TH/TP" and "TH" on the back of the fireplace switch.
Slide the switch on the receiver to the "Remote" position. Close the control-panel cover.