There once was a time when choosing and replacing a light bulb was an easy task that anyone could do. Most anyone can still perform the task, but now there is a vast array of different types of light bulbs and fixtures, and, they don’t all get changed the same.
Fluorescent lighting started out as being long tubes fitted into a ballast, but they are now available in U-shaped and in circular light bulbs as well. U-shaped bulbs are used underneath cabinets, and they only have a ballast at one end, while circular bulbs are used in sockets. Fluorescent lighting also used to provide only one type of bright, white, glaring light. They now come in assorted colors and different shades of white. Some of these examples include Cool and Soft White, Black Light, Aquarium bulbs, and Grow Lights.
The first thing you need to know is, that anytime that you need to change a fluorescent light bulb or a fluorescent tube, be sure that you replace the bulb or tube with the exact same size that was in the light. This is assuming, of course, that the existing light bulb was the correct size. And you should never exceed the maximum wattage recommended by the manufacturer! That could create an overheating in the ballast which could result in a fire hazard!
The traditional fluorescent light consists of four parts: a bulb holder, a ballast, a switch, and a starter. Basically, the bulb holder keeps the bulbs; the switch turns the light on or off; and the starter and the ballast provide the electrical current that ionizes the gas inside of the bulb.
It’s difficult to tell when you need to change a fluorescent light bulb because it doesn’t appear to be “burnt out” out like an incandescent light bulb does. If, however, you notice that one end or the other is dark, that could be as sign that the light bulb needs to be changed, or will soon need to be replaced. The flickering of a fluorescent light bulb could be the result of a bad light, or, it could signal that you need to replace the ballast. If your light emits a buzzing or a low humming sound, there is probably a problem with the ballast too.
The most reliable way you can check a fluorescent light bulb to see if it is still working or not, is to remove it from its existing ballast or socket and put it in another ballast or socket that you know works.
Another thing that you need to know is that ballasts and sockets can actually be damaged by forceful or improper removal or installation methods. Light bulbs are generally unscrewed and screwed into a socket, taking care not to break the bulb or to force it into the socket. If the light bulb doesn’t fit, don’t try to force it! The same goes for installing a tube into a ballast – if the tube doesn’t “snap” into place easily, then it might well be the wrong size.
Before you change a fluorescent light bulb, you should turn the light off so there is no electricity entering the ballast or socket. Then, either unscrew the bulb or carefully push the tube to one side and pull it down and out. To install the new bulb or tube, either screw a new one in, or place one end of the tube into the ballast, push to the side, and snap the other end into place.