LEDs replaced florescents but get hot

tinstaafl wrote:
I bought 28 "48SMD LED Light panels)to convert the 12 Volt lights to LEDs. So far I have converted two florescent fixtures, removing all the florescent components, circuit board, etc., and sticking the LED panels to the fixture housing and then replacing the fixture lens cover.

Everything works fine except that the LEDs are giving off a great deal of heat. I thought that the LEDs would be extremely efficient since all the consumed energy converts to light, not heat. That does not appear to be the case as there is a lot of heat being produced. Removing the lens cover from one of the fixtures I cannot keep my hand on the 48 LED panel because it is too hot.

I bought these LEDs on E-Bay for $2.75 each. Are these just cheap (crummy) LEDs or are they supposed to be that hot? At this point I'm not sure I want to convert the rest of my fixtures.

Thanks in advance for whatever comments or suggestions you might offer me.

First, LED's are more efficient than incandescent lights but still VERY VERY inefficient, on the order of 15% of the energy is converted to visible light, the rest is heat. (incandesent lights are on the order of 1% efficient on light conversion) So, they will get warm. Second, many cheap LED arrays, use simple dropping resistors to set the voltage. Good as long as the voltage is constant. But in an RV when the charger is on, voltage can be as high as 14.6V, or as low as 11.5V with no charger and low batteries. These cheaper arrays are designed for a nominal 12V, 14.6 really increases the power and heat. enought that I've had the LED's get hot enough to melt the solder at 14.6V. Solution is to buy quality units that are regulated to supply a constant current to the LED's. Then they are warm to the touch and will last.