How to Install a Hardwired Fire Alarm

Assemble the components of the fire alarm on a table. Twist the cover off the alarm with a counterclockwise motion. Insert the battery backup in the battery compartment inside the alarm. Twist the cover back on the alarm with a clockwise motion.

Turn the alarm over. If wires are attached to the bottom of the alarm, strip 1/2 inch of insulation from the end of each wire with wire strippers; otherwise, insert the wire connector tab into the slot on the bottom.

Trip the circuit breaker at the fuse box that provides electricity to the room where you will be installing the fire alarm. Place a ladder against the wall in front of an AC outlet that is at the base of the wall.

Cut a hole in the wall, just below the ceiling, with a utility knife. Shine the beam of a flashlight into the hole to verify that there is an electrical junction box inside the wall.

Cut a larger hole in the wall with a drywall hand saw so you can pull out the wires attached to the electrical junction box. Dispose of the cut piece of wall.

Push the wires from the hole through the center of the alarm's mounting plate. Place the plate on the wall over the hole. Screw wood screws through the mount and into the wall with a Phillips screwdriver.

Wind the end of the black wire attached to the alarm around the end of the black wire that comes out of the hole. Wind the end of the white wire attached to the alarm around the end of the white wire coming out of the hole. Wind the end of the copper-colored wire attached to the alarm around the end of the copper-colored or bare wire coming out of the hole.

Screw an electrical nut connector over each pair of twisted wires. Stop screwing the nut over the wires when resistance is felt. Place a strip of electrical tape over the end of the yellow wire that is attached to the alarm to insulate it from the other wires. The yellow wire is used when interconnecting an alarm with other alarms.

Push the wires into the hole. Place the alarm against the base. Twist the alarm onto the base with a clockwise motion.

Restore the electric power at the fuse box. Return to the alarm. Verify that the red LED is flashing to indicate the alarm is receiving power and is operational. Press the "Test/Reset" button on the side of the alarm for a second to sound the alarm.