Fluorescent Lights

SuperTester123 says:
Thanks! This saves me from replacing our kitchen lighting until we do our big renovation.
Thanks! This saves me from replacing our kitchen lighting until we do our big renovation.

A new fluorescent fixture is inexpensive and easy to install, so replacing rather than repairing is often the better option. Before you do, however, quickly check the components in this order: the tube, the starter (if any), the sockets, and the ballast.

Very old fluorescents have both a heavy ballast and a starter. More recent models have rapid-start ballasts and no starter. The latest models have electronic ballasts, which are nearly maintenance-free.

Fluorescent fixtures are often flimsy. Check that sockets are firmly seated and not cracked. Tubes should fit snugly between the sockets.

An old, delayed-start fluorescent flickers a few times before coming on as the starter delivers a burst of energy to get the tube going. A newer, rapid-start fixture has a ballast that supplies extra power when turned on so the light comes on immediately. A circular fluorescent differs from a straight tube only in shape.

Troubleshooting Fluorescents

When faced with the following problems, work your way through the solutions one by one until the light functions.

Does not light
Twist a tube to tighten it or replace the tube. If there is a starter, replace it. Replace a damaged socket. Replace the ballast or the fixture.

Tube is blackened
If only one end is black, turn the tube around. Replace the tube if both ends are black.

Flickers or takes a long time to light
Tighten, turn around, or replace a tube. If there is a starter, replace it. Replace the ballast or the fixture.

Hums and/or seeps black gunk
Don't touch the seepage with your fingers. Wear gloves. Tighten the screw securing the ballast. Replace a leaking ballast or the fixture.

Fluorescent Types
Rotating Tubes

If a tube is black at both ends, replace it. If it flickers or does not come on, try rotating it in the socket until it seats firmly or until the light comes on.

Removing and Replacing Tubes

To remove a tube hold both ends and rotate until you feel it come loose at one end. Guide the pins out of the socket. To install a new tube, insert pins into one socket and guide the pins into the other socket. Rotate the tube a quarter-turn until you feel it seat or until it lights.


If a fixture has a starter, replace it every time you replace a tube. Be sure to buy a starter with the same serial numbers as the old one. If a tube is slow to light, tighten the starter. If that does not solve the problem, replace the starter. If the light still doesn't work, the ballast is to blame.

Replacing Sockets: Step 1

Replace a socket if it is cracked or does not hold the tube firmly. Some sockets just slide out, while others are held in place by a screw. If you cannot remove the wires, cut them near the socket.

Replacing Sockets: Step 2

Buy a replacement to match the old socket. Strip 3/4 inch of insulation from each wire end and push the wire end into the hole of the new socket. Push the new socket firmly into the fixture.


Comments (1)
SuperTester123 wrote:

Thanks! This saves me from replacing our kitchen lighting until we do our big renovation.

3/1/2010 10:07:31 AM Report Abuse
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