How to Replace a Fluorescent Light Ballast

A broken fluorescent light ballast often gives itself away by leaking an oily dark substance or making a large humming noise. If you notice any of these problems with your fluorescent light, consider replacing the ballast rather than replacing the entire light fixture. Finishing this project on your own can save you money as well add to your electrical experience, enabling you to tackle larger projects in the future.

Before starting to repair the fluorescent light ballast be sure to turn off the electricity to the fixture as well as flipping the circuit to this part of the house to avoid a shock. Test the terminals to make sure the electricity to your fluorescent light fixture is off using a voltage meter. Then proceed by removing the cover plate of the fixture, the fluorescent tube, and the diffuser.

Next remove the sockets that held in the fluorescent light fixture tube. This can be done by sliding the sockets out of the slots that hold them to the fluorescent light fixture. Sometimes you must loosen the mounting screws that secure them to the fluorescent fixture and then remove the entire socket. Then remove the wires from the sockets. You can do this by loosening the screw terminals and removing the wire or cutting the wire at least 3″ away from the socket as needed.

Removing the old ballast in order to replace it requires a ratchet wrench. Be sure to have one hand on the ballast to prevent it from falling. Take the old ballast to the hardware store to be certain that you get a new ballast for your fluorescent light fixture that has the same rating as the old.

When you have the new ballast, use the ratchet wrench to put it into place, taking care to install it in the same direction that the older ballast was installed. Attach the wires protruding from the ballast to the new sockets using either wire nuts or the screw terminals. Slide the sockets back into place and replace the bulb, cover plate and diffuser. Turn on the electricity and test your work.

Replacing fluorescent light ballast is an easy job if you have some general wiring experience. Of course, you should check and make sure that replacing the ballast is more cost effective than replacing the entire fixture, unless the light fixture itself is fairly unusual. As always, you should also consider calling a professional if you are uncomfortable or unable to complete this task safely.