Incandescent bulbs generate significant amounts of heat. A 100W incandescent can be replaced by a 10W LED, meaning there are 90W more of heat that the traditional bulb could handle. Traditional bulbs were meant to run hot. Traditional bulb filaments glowed at approximately 3200°! The heat was concentrated at the filament, and even though the glass burned your hand, the heat was greatly reduced by the low thermal conductance of the filament supports. The sockets were ceramic and meant to take the excess heat.
LED lights are quite different. While they are highly efficient and generate minimal heat output compared to incandescent, some power goes into converting the high voltage AC into low voltage DC required by the LED which can produce heat.
So, what is the difference between AC and DC?
Both AC and DC describe types of current flow in a circuit. In Direct Current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC) changes direction periodically. The voltage in AC circuits also periodically reverses because of the current changing direction. Most modern digital electronics will use DC. However, most homes are wired for AC.
Hence, the LED indeed produces heat during this AC to DC conversion. The extra heat is all dissipated in the small neck of the bulb just above the socket.
This generates so much heat in such a small space that LED lights bulbs are designed with a metal heat sink in this area to dissipate the heat. Consequently, when installed in a confined space, it can raise the temperature of the trapped air considerably. While temperatures of 250°F don’t damage traditional bulbs, temperatures of approximately 175°F or higher are threatening to the electronics in an LED. The electronic chips and capacitors often run much hotter internally than the air around them. In short, an LED bulb in an enclosed space will get hot and fail prematurely or burn the components. We highly recommend that you allow some room for the heat to escape to take advantage of the long lifespan of our LED bulbs.