Troubleshooting Fluorescent Lights that Hum

There are not many things more annoying than humming fluorescent lights. Fluorescent lights are used almost extensively in businesses because they last a long time. Older homes often feature them as well for the same reason. These lights are also more efficient which means they cost less to run. Fluorescent lights are tubes filled with gas. The tubes are fitted with metal contacts which are inserted into the light fixtures. These sockets transmit electricity through the light tube contacts which, in turn, charge the gas in the tube which then illuminates. A few things can cause fluorescent lights to hum and this article will help you troubleshoot the problem.

Look at the Tube

You'll have to remove the light tube. You'll need to remove the light diffuser over the fluorescent light tubes (if there's one). These are typically easy to remove by pressing two tabs on either side of the fixture. Some diffusers may have screws to remove. When the diffuser is removed simply look at the light tube. If you see black or gray spots on the glass then the light is dead or is about to die which explains the hum you heard previously as that happens before they die.

Socket is Loose

Now you need to practice some safety precautions. Turn the light off at the switch and the main breaker. Frequently use the voltage tester to be certain the electric is off.

Push gently on the tube and if it moves then the contact points and socket are loose. Grip both ends of the light tube and pull down to remove it from the fixture. Place the light to the side. Physically touch the socket and try to wiggle it back and forth. If it is loose simply tighten the screws.

Damaged Contacts

A set of damaged contacts is easy to spot. Look for bent prongs as well as darkened contacts. If this is the case then you will have to replace the sockets. Remove the few screws that hold the sockets in place. You will be able to easily remove the socket to see the wires. Loosen the screws holding the wires in place, discard the old socket then install the new one connecting the wires as they were previously. If it's oxidation clean with alcohol.

Old Fluorescent Lights and Starters

Homes that have really old fluorescent lights also have starters installed in the fixtures. Once these begin to go the lights will hum. The starter is attached to the fixture and is usually cylindrical. Look for it below one of the light tubes. Push on the starter and twist then remove. Replace it with an identical starter.

Wiring Woes

This is another issue with old home that have fluorescent lights. Remove the light diffuser then remove the fluorescent lights. Remove the socket in the fixture to access the wires. Look for oxidation, burnt coverings and brittleness. Disconnect the socket and trim the wires then strip them. Attach the new wires to the old with a wire cap.