Hi, thanks for using JustAnswer.com. F30 is a probe error. It is displayed anytime the resistance value is out of range. This is easily diagnosed by taking a reading of the probe resistance at the control. At room temperature, it should read about 1090 ohms of resistance. An ohmmeter can be purchased at any hardware store for about $15.00 or less.
There is likely a break in the wire harness from the probe to the control....a meter will tell you for sure