LED lights often flicker after installation because the dimmer or switch is not compatible with the new lamps or fixtures, the LED driver is struggling, or the bulb and fixture are a poor match. Less often, flickering can come from a loose connection or a problem with the electrical supply, so not every flicker means there is a wiring fault.
Because several causes look the same, it helps to note when and how the flicker happens.
Dimmer Compatibility
Dimmers are the most common cause. Many older dimmers were designed for incandescent bulbs and do not control LEDs smoothly, which can cause flicker, buzzing, a limited dimming range or lights that will not fully turn off.
Some LEDs also need a minimum load to dim properly. A dimmer controlling only one or two low-wattage LEDs may flicker even if both products are labeled dimmable. Replacing the dimmer with a compatible model often helps, but it does not solve every flicker.
LED Drivers, Lamps and Fixtures
Every LED has a driver that converts incoming power to what the LED needs. A low-quality or failing driver, or one that overheats, can cause flicker. Integrated LED fixtures have drivers built in, so a driver problem may require replacing the driver or the fixture. Heat can make driver problems worse, so flicker that appears only after lights have been on for a while may point to overheating.
Bulbs and fixtures must also suit each other. Non-dimmable bulbs on a dimmer, bulbs that are not rated for enclosed fixtures, or mixing different brands on one circuit can lead to uneven or flickering light. Smart bulbs used on a regular dimmer are another common cause of flicker.
Electrical Supply and Connection Problems
If flickering affects several rooms, happens with no dimmer involved, or changes when large appliances start, the cause may be in the circuit rather than the lights. A loose connection at a switch, fixture or junction can also cause flickering and heat. Those situations call for electrical troubleshooting to find the source.
This post is about flicker that starts after LEDs are installed. A brief dip when a large appliance turns on is a different issue and is often unrelated to the LEDs themselves.
When Flickering Needs Attention
Flicker that comes with buzzing, a warm switch or fixture, a burning smell or breakers that trip should be checked promptly. Turn off the lights if it is safe to do so, and call 911 if you see smoke or fire. Do not open fixtures or test wiring yourself.
Many homes in Utah have switched to LEDs on existing dimmers and fixtures, which is why compatibility issues are so common after upgrades.
If new LEDs in your Salt Lake City home keep flickering, our LED lighting installation service can check the bulbs, dimmers and fixtures and recommend a compatible fix.