How to Install a Can Light

Preparation

• 1

  Prepare the can light for installation. Open the cover on the wiring box and look inside. There will be one white, one black and one green wire or in some cases, just a green grounding screw. On the sides are knockouts for armored cable, on the top are knockouts for sheathed cable.

• 2

  Remove one knockout from the wiring box for the cable. If using sheathed cable, remove a smaller knockout from the top, rather than one of the round knockouts on the sides.

• 3

  Insert the cable into the box. For sheathed cable, remove six inches of sheathing from the cable and 3/4 inch insulation from the wires and insert it through the top knockout removed. Armored cable comes with connector. Unscrew the connector and insert the end of the cable into the box and reattach the connector to hold it in place.

• 4

  Connect the bare or green ground wire from the cable to the bare or green ground wire or screw in the box. Twist wires together with a side cutters and cap with an appropriate size wire nut.

• 5

  The black and white wires in the box will be stranded wire. Connect the white wires together by simply holding them together and capping with a wire nut, twisting it tightly on. If a gentle tug doesn't pull the stranded wire out, it's tight. Repeat for the black wires.

• 6

  Put the cover back on the box, snapping it in place.

Installing the Can Light

• 7

  Position the light where you want it between two joists or rafters. If installing from an attic to a room down below, poke through the ceiling from below to determine the position from above. Then cut out a circle the same diameter as the can light. See caution about insulation.

• 8

  Nail the four supports into place. If installing from the attic space above the room, insure the light protrudes just enough to be flush with the drywall. When installing into a suspended ceiling grid, wire the can lights before installing the tiles, but don't clip them in place. Once the tiles are installed, then clip the supports to the grid.

• 9

  Turn off the power to the circuit the light will be on. Simply turning the switch off is not good enough; turn off the circuit breaker. Wire the can light whip to the junction box. Connect ground wires first, then the white wire to the white wire in the box, and finally, the black wires to each other. Cap the wire connections with wire nuts.

• 10

  Install the trim. Different kinds of trim go on differently. The most common type, a ring that fits against the ceiling, is installed with two springs that attach to tabs inside the can. Use a pencil or pen tip to guide the spring to the tab and slip it over. The springs will hold the trim snugly to the ceiling.

• 11

  Install a properly sized light into the can. Can lights have different ratings and using a light with a higher wattage than tested for will cause the light to function intermittently as the light overheats and cycles off and on. Use the correct size lights.