My mother has an oven that is 20+ years old and last week she turned it on, the heating element cracked, and there was was a small fire in the oven. Obviously time for a new oven, but before she goes and buys a new one and sets up install, I am wondering what could have caused the heating element to crack and if she needs to have an electrician check the wiring before doing anything else. Could a wiring or electrical problem cause this kind of issue? Is this something that appliance repair/reseller/installer checsk for, or is it better to have a certified electrician look at this first? Any advice would be helpful. We do not live near each other so I cannot check this out myself.