When we purchased our house we inherited an old gas wedgewood stove. It has worked great until recently, but now we are having trouble with all four burners. On one of the burners, when we turn the gas knob the inner circle (each burner has an inner and outer circle of flames that will light) will light on its own, but we have to light the outside by hand. On the other three we cannot even get the inside circle to light without using a lighter or match. Is this something that we can repair on our own? Any suggestions for how we go about doing it?