What you may be noticing
- The light shuts off after 15 minutes to an hour, then turns back on later
- Only one can light in a group cycles on and off
- The problem is worse on hot days or in rooms under the attic
- The trim or ceiling around the light feels warm
Common possible causes
Thermal protector cycling
Most incandescent-era recessed housings have a heat sensor. When the can overheats, it cuts power, cools down and resets, which causes the on and off pattern.
Bulb wattage too high
Each housing is labeled with a maximum bulb wattage and type. A larger bulb, or a flood bulb in a can meant for a smaller one, can overheat the fixture.
Insulation touching a non-IC housing
Cans not rated for insulation contact need clearance. Attic insulation added later can bury them and trap heat.
LED retrofit issues
Retrofit LED trims usually run cooler, but a poorly seated retrofit, an incompatible dimmer or a failing driver can make lights drop out.
Loose socket or connection
A worn socket or loose wire inside the housing can interrupt power and cause heat at the same spot.
Safe checks you can make
- Read the label inside the housing (with the light off and cool) for maximum wattage
- Compare the bulb you are using to that rating
- Note how long the light stays on before it shuts off
- If you can safely look in the attic, see whether insulation is piled on the cans
What not to do
- Do not use a higher wattage bulb to make the room brighter
- Do not bypass, remove or tape over the thermal protector
- Do not pull insulation away from cans with your hands near wiring
- Do not keep replacing bulbs if the problem keeps coming back
Can you sort this out yourself?
Some cases are a quick fix. If the bulb is over the rated wattage, swapping it for a dimmable LED bulb of the right type often stops the cycling for good, because LEDs make far less heat. Making sure the bulb is screwed in firmly helps too. If the right bulb is already in place, the light keeps cutting out, or insulation is packed around the housing, the answer may involve replacing the can, adding a retrofit trim or correcting attic clearances, which is work for an electrician.
When professional help is appropriate
- The light keeps cycling even with the correct bulb
- Several recessed lights are cycling at once
- You see browned trim, discolored ceiling or a hot smell
- Insulation is in contact with cans that are not IC-rated
- LED retrofits flicker or drop out on a dimmer
What an electrician typically checks
An electrician will identify the housing type, check whether it is rated for insulation contact, and confirm the bulb or retrofit trim matches it. They inspect the socket, wiring and connections inside the can, and they test any dimmer on the circuit for compatibility with LED loads.
Fixes range from installing a properly rated LED retrofit trim to replacing old cans with IC-rated or canless fixtures. In many older Chattanooga homes with attics that have been reinsulated, correcting clearances is part of the job. Bigger lighting refreshes often fall under indoor lighting installation.
Keeping it from coming back
Stick to the bulb type and wattage on the housing label, and choose dimmable LEDs where dimmers are used. Before adding attic insulation, have someone confirm whether your recessed cans are IC-rated or need clearance; attic electrical work often covers that check.
