Oven taking too long to preheat
Hi! I have a White-Westinghouse gas oven with electronic ignition, model #GF835FXW and serial #XFF7016T. It is approximately 23 years old. It was here when we moved into this house 2 years ago. Two times in the past week ,(9/20) and (9/23), when I preheated the oven, it took a long time to reach the temperature I put it on. On 9/20, it took @ 1 1/2hours to cook two frozen pizzas. That night I purchased an oven thermometer to check the temperature. I set it to 400 degrees and it took about 25 minutes to reach that. On 9/23, the same thing happened when I was trying to cook a roast. I had to turn the oven up more than 400 degrees and then back down once it heated up. Once it reaches the right temperature, it does stay there. I checked it again yesterday morning, 9/24. Once again, I set it to 400 degrees and it took @ 25 minutes to reach that temperature. This is the first problem I have noticed with this oven.
Does anyone have a possible reason for this? Is it even worth getting fixed?
Any help would be appreciated,
Irish