Installing a Dimmer Switch

Introduction

Want to shake things up? Want to affect the mood? An effective way to quickly change the mood of a room is by dimming or brightening the lights. A softer light results in a more comforting, relaxing atmosphere. Brighter lighting is more suitable for normal room use and reading. An easy way to control your lighting is to install a dimmer switch. Dimmer switches come in four popular styles: dial, slide, touch pad, and combination light switch/dimmer slide. Since dimmer switches come in different shapes and each operates a little differently, you should always follow the instructions included with the switch for installation and operation. However, most dimmer switches have similar installation requirements that will be discussed in this tutorial.

IMPORTANT: Read this before you start


 
  Time To Complete
  • Beginner - 30 to 45 minutes 
  • Intermediate - 20 to 30 minutes
  • Advanced - 15 to 20 minutes
 
  Materials List
  • Wire nuts
  • Dimmer Switch Plate
  • Dimmer Switch
 
  Tools List
  • Wire strippers
  • Needle nose pliers
  • Screwdriver
 
 
  • Make sure you turn off the circuit you will be working on. Locate the breaker or fuse and properly disable.  
 
  • If you are using a plastic work box, be sure to connect ground wires directly to ground leads on the new switch instead of to the work box.  
 
  • Make sure you connect the wiring to the correct terminals on your new switch. The black wires (hot) go to the hot leads. The white wires (neutral) go to the neutral leads. Green or bare wires go to the grounding terminal.  
 
  • Use insulated tools as an extra safety measure.  
 
1. The first and most important step is to turn off the circuit that you will be working on. Find the right breaker in the breaker box and flip it to the "Off" position. If you have a fuse box, find the right fuse and remove it completely from the panel. Double check that the circuit is off by turning the light switch on. If the light stays off, then you have selected the right breaker or fuse.
2. Use a screwdriver to remove the old switch plate.
3. Remove the old switch from the workbox by unscrewing the screws on the top and bottom of the switch.
4. Disconnect the wires that are connected to the light switch.
5. Using a wire cutter, cut off the bare wire just below the plastic insulation on all three wires. Then use a wire stripper to strip off about 3/8” of the insulation. This will give you a clean piece of wire for the new connection to the dimmer. If needed, strip the wires that are already attached to the dimmer switch.
6. Connect one of the black wires in the workbox to one from the dimmer switch by placing the bare wires next to each other. Then twist on a wire nut. Make sure that the bare wires are completely encased in the wire nut. Do the same for the other set of black wires. The white (neutral) wires should be connected together and capped with a wire nut. Be sure to tie together all the ground wires also.
7. Bend the wires in a zigzag pattern so that they easily fold into the workbox. Push the switch into place. Adjust the switch so that it is perpendicular to the floor. Tighten the two screws that hold it in position in the workbox.
8. Install the new dimmer switch plate over the dimmer switch.
9. Switch the breaker back on (or reinstall the fuse). Test the dimmer to make sure your installation was successful. If the dimmer doesn’t work, turn off the breaker and double check your wiring connections.