For some reason, my oven does not light when the temp changes or the humidiy changes outdoor a lot. the glow bar comes on, but the even though I hear a click, the temp does not go up in the oven. After I turn it on and off several time over a 15-30 minute period, it will usually come on. I can picture not lighting at 5 am on thanksgiving and having to take ten people to dinner. Any ideas?