The range works fine, so does the broiler, and when I click Bake I hear the typical click, and the display shows "Pre" as usual. However, the oven stays cold. There is no orange glow under the oven floor, and no smell of gas, though the convection fan seems to be blowing normally when I open the door during this problem.
I'd like to order the correct part and install it myself, so can someone help me figure out what's broken? I should note that last night I set the oven to 350 and forgot about it, then about three hours later went to turn it off and it said "Pre." I'm thinking I burned it out- that it did reach 350 then broke and the temperature dropped, so it went back into preheating mode, but was unable to ignite? I have had times in the past where the oven has been used for hours on end with no problem.
Thanks for the help.

-Chris