I was baking some chicken in the oven just now, and I heard a gigantic crash in the oven. I rushed over, turned off the heat and opened up the door. Inside, I saw my half-cooked chicken sitting on the rack. All over the bottom of the oven (and some on the rack) were the remains of my pyrex dish. Broken in to thirty or forty shards of tempered glass. I just looked at the oven thermometer I have in there and it’s over 500, even though the dial was set at 400. I can’t imagine how hot it got in there. At least 550.
I may need to have maintenance come and look at my oven…
So, fried chicken for supper?
Just be glad it wasn’t Duck, Man.
thank you, i’ll be here all week
I’m ashamed of you, buttonjockey, coming off with a crack like that. You’re liable to shatter someone’s peace of mind if you’re not careful.
i’ll be here for at least the next two years 
Sounds like your thermostat pipe is punctured. That’ll give you runaway heat in your oven.
That’s certainly one possibility. The important thing to know is what temperature your oven thermostat was reading. You can check this by turning the thermostat dial up and down and seeing what temperature it “clicks” at. If the thermostat thought it was below 300 °F, then I’d guess it was the culprit. OTOH, if it was reading beteen 375 and 425 °F, then you may have just had a thermal stress failure. This can happen when some relatively cool water and chicken juice runs out of the chicken and hits the much hotter Pyrex.
Unless you have a shielded mercury thermometer, yours could have been thrown off by radiant heat from the electric elements or gas burner. Bi-metal dial thermometers are notorious for this.
FWIW, I’ve had the same thing happen twice. Once with a chicken in the oven and once when I foolishly ran tap water into a Pyrex sauce pan where I had just burned the broccoli (very bad smell!!!).
To test the oven, I would suggest heating it up empty to about 350 °F. When it reaches temperature (the elements will stop glowing or flames will go off), put the thermometer in the oven, then check the temperature. If it’s within 25 °F of setting, it’s okay.
Good luck,
Rhubarb - Former appliance repair person.
[sub]So where’d you go for dinner?[/sub]