Occasionally the oven will quit heating. When I turn the temperature knob I hear a click but the oven light will not go on and the oven will not heat. A day or two later it will work again. I was broiling chile peppers today and it went out again. When it cooled down it began to work again. A repair man came over a few weeks ago and it started working when he was here so he said there was not much he could do. Could this be a heating element going out or is it a switch or a limiter. Any help would be appreciated. patrickC