Hi, our GE over burned out an oven igniter a little over a year ago. I bought a replacement and installed it at that time. The oven worked perfectly for about a year (13 months) until that replacement igniter also failed. 
I installed another new one this past Sunday and tested it - the oven came on immediately and began heating up normally so I shut it off, reassembled everything and declared victory. On Monday however, only one day later, my wife tried to use the oven but after 20 minutes it was still cold. I looked underneath from the broiler and found again that the brand new igniter is not glowing when the oven is turned on.
Since it worked initially, I don’t think there’s a problem with the safety valve. What could cause such failures? The first replacement that lasted only a year was bad enough but the second one only a day - without even using it! 