Too Cool in the Kitchen
If you can't stand the heat in the kitchen, your oven is probably working. We had the opposite problem recently - a decidedly cool kitchen. After weeks of our oven taking longer and longer to heat up, it suddenly stopped heating at all. Thanks to a classic Fix-It-Yourself book, Google and a bit of DIY troubleshooting I found the problem. The Glow Bar Igniter in our oven was no longer heating sufficiently to start the gas oven. Happily, it was an easy fix.
One quick note of caution - working around 120VAC power and natural gas isn't a trivial thing. If you aren't confident that you can work on your oven (or any major appliance) safely - don't do it.
With that said, troubleshooting our oven wasn't too tricky. The symptoms were clear - longer and longer oven pre-heat times until it eventually didn't heat at all. I don't have a clamp-on multimeter (just a probe-style multimeter) to verify how much current the glow-bar ignitor was pulling, but thanks to information from a diy oven repair video I took a chance. For about $27 I received an exact replacement glow-bar ignitor and was able to install it, without rushing, in less than an hour.
The end result is a warm kitchen filled with oven fried potatoes, fresh-baked breads and cookies, and one very happy baker! One more win for DIY frugality!
Youtube - How to Fix a Gas Oven that won't Heat