The thermal protector, or heat sensor, inside your recessed lighting fixture disconnects the electricity to the light socket when the temperature inside the fixture reaches unsafe levels. This safety feature protects your home against accidental fires. When the thermal protector breaks, your light bulb begins to cycle off and on at lower temperatures than the rating on the protector is designed to protect against. Replace the thermal protector to alleviate this issue. Ensure your thermal protector is recommended by your recessed lighting manufacturer or the ratings on the replacement thermal protector matches the original protector's ratings.
Turn off the breaker supplying electrical current to the recessed lighting fixture.
Remove the bulb from the light fixture. Hold a non-contact voltage tester next to the light socket. The sensor does not light when electrical current is not present.
Remove the trim. Depending on the design, the trim is held by two small coiled springs attached to the trim and the inside of the recessed fixture, or two butterfly springs on each side of the trim.
Unhook the springs from the inside of the recessed fixture to release the trim, or pull the trim away from the ceiling and squeeze the butterfly springs with your fingers to release the trim.
Look inside the recessed lighting fixture to locate the wing nut on the sidewall of the fixture. The wing nut holds the socket and socket bracket in the fixture. Remove the wing nut. Let the socket and socket bracket drop from the fixture. Do not disconnect the wires to the socket.
Find the thermal protector at the top of the recessed fixture. It is a small silver rectangle with two wires attached to it. Slip a slotted screwdriver between the thermal protector and the top of the fixture. Pry it from the slots cut into the metal fixture housing.
Cut the thermal protector's wires with wire cutters to remove the old thermal protector. Use wire strippers to remove about 3/4 inch of the insulation from the wires left in the fixture.
Connect one wire from the replacement thermal protector to one of the wires from the original thermal protector by installing a twist-on wire connector onto the two wires.
Connect the remaining wire from the new replacement thermal protector to the remaining wire from the original thermal protector with another wire connector. The two wires from the thermal protector can connect to either wire from the original.
Insert the thermal protector into the slots in the recessed fixture housing where the original was located. Use electrical tape to secure the wires to the top of the recessed can.
Replace the socket and socket bracket into the recessed fixture. Secure the socket and bracket with the wing nut.
Install the recessed housing trim into the fixture by reversing the steps you used to remove it. Replace the light bulb.
Turn on the breaker to supply electricity back to your recessed light fixture.