My multifunction soft touch oven will only cook for about an hour and then it starts continually beeping and it cools down. The function screen displays F1. I then have to turn the oven off and wait for about 20minutes before it will turn on again. My husband wrote some numbers down from the back of the oven-I don't know if this will help you answer this question but-here they are, FPTM620 WW87017 WYD118995.