Troubleshooting Fluorescent Light Fixtures
- There are a couple of reasons that a fluorescent light does not work or just flickers. The first thing to check is the fluorescent tube. Look at the ends and see if they are very dark. This indicates that the tube has served its life and needs to be replaced. Even if it is still flickering, the time is running out on the life of the tube.
The ballast on the light fixture will cause this problem as well. The quickest way to test ballast is to use a known good tube. Take out the flickering or non-working tube and install a known good tube from another fixture. If the good tube does not work, the ballast is faulty.
To replace ballast, first mark the wires with tape so that the new ballast will be wired correctly. Disconnect the wires from the faulty unit. Remove the ballast by unscrewing the two screws that hold it in place. Reinstall the new unit and connect the wires. - This can be caused by a tube that has low mercury content. For the first few hours of operation the ends will warm quickly while it takes time for the center to warm. This is not a sign of a faulty tube. This type of low mercury fluorescent requires a break in period. The best solution is to allow the fluorescent light fixture to stay on for a few hours.
- This problem occurs because a fluorescent lamp fixture is too cold. Check the location of the fixture and make sure that the air conditioning vent is not blowing directly on it. This will keep the bulb from warming up and not be able to light fully.
This could be caused by faulty ballast as well. Check the fixture by installing a known good tube. - First, make sure that all the tubes are seated properly in the socket. Sometimes a twist of the tube in the socket will correct this problem.
A fixture that is not properly grounded will cause this as well. Many homes still have two-prong wall outlets, and people use cheater adapters to plug three-prong plugs with a grounding prong. This will not work properly on a fluorescent light fixture.