Flickering lights are a common problem, especially in older structures. And frankly, due to the prevalence of flickering lights in horror movies, it is easy to get frightened when it happens. However, there are many other reasons to fear as well, since sometimes a flickering light can be an indication of an electrical problem-and one that may get costly. But it’s important to keep in mind that there are several common reasons for a flickering light.
Sometimes the problem is the bulb
Flickering lights can be caused by something as simple as a loose bulb. The first step in determining why your lights may be flickering is to check and see if the bulb is loose, and if it is, just twist it in so that it sits tightly enough into the socket. This will ensure that the necessary connection for uninterrupted light is made.
Even if the bulb is tightly in its socket, the problem could still lie with the lightbulb. Certain types of bulbs have a tendency to flicker. Florescent lights, for example, can flicker frequently due to a variety of environmental factors, including cold temperatures. They can also flicker when the bulbs burn out the while they are in the socket-it is actually recommended that the tubes are replaced in order to prevent this. And finally, florescent lights will flicker due to the way that the phosphors power up to the maximum lever. All of these factors are normal with this type of bulb and should not be a concern.
With LED bulbs, flickering can be caused when dimmer switches are used. LED lights typically use a lower voltage than standard lighting and dimmer switches are built to handle higher electrical loads, which is why the flickering may occur. Before installing an LED light, it is best to check compatibility and test the bulb to discover incompatibilities quickly.i
Loose or faulty fixture switches or light plugs
If you discover the bulb is not the cause of flickering, it’s time to consider checking the connections. If there is a loose connection between the light fixture and the lightbulb itself, or between the switch and the fixture, it may be the source of flicker. You can check by wiggling the switch to see if it induces a flicker and if it does replace the switch. If you are using a lamp, the flicker may be caused by the electrical connection to the outlet. You may easily test this by unplugging the lamp, adjusting the prongs and plugging it back in. Frequently, this will solve the problem.ii
Voltage Fluctuations from Large Appliances
If you notice that the flickering you see only occurs when a large appliance with high wattage is running, it is likely that the cause of the flickering is because the voltage is fluctuating too much. You may be able to determine if this is the cause by listening to the breaker panel when certain appliances are running. If you hear a buzzing or crackling that is correlated with a particular appliance, then that is likely the cause of the flicker. Electricity enters the home at a standard 120 volts and can fluctuate between 115 and 125 normally, but if it deviates from this range, you will likely experience problems. There are other signs to watch for that also indicate this is the problem. If the voltage isn’t right, the lights may dim unexpectedly and light bulbs will frequently burn out. If you suspect this is the problem, it can be checked with a voltmeter and if it outside of the standard range, it is likely that you have discovered the problem. You may want to check with an electrician prior to making any changes, but in some instances when the voltage is regularly higher than average, purchasing 130-volt light bulbs may take care of the problem.iii
It’s important to keep in mind that your home shares a transformer with other homes in your neighborhood, so if you have flickering lights, it may be due to heavy usage by your neighbors. It can also be the result of damage caused to power lines during storms or if there is a downed tree. If you suspect this may be the case, it can only be confirmed by an electrician or a representative from the power company.iv
Loose or old electrical wiring and equipment
There is always the potential that any flickering could be caused by old or loose wiring. One indicator is if you notice a lot more flickering than normal when there have been no changes made to the electrical system. This is the worse-case scenario as faulty wiring is one of the leading causes of house fires. If you have tried troubleshooting all of the previous potential causes of flickering, it may be time to call in an electrician to check the wiring. It is also a good idea to look at the service conductors in the main electrical panel as there is the potential that they may be loose as well. If there is an outdated breaker box that has worn connectors you may also experience flickering of the lights. It could also potentially be a switch failure or a combination of any of these issues. However, if this is the source of flickering, it is imperative that an electrician is contacted immediately as any of these conditions poses a hazard.v