I just replaced the thermocouple in my gas heater as the pilot wouldn't stay on after lighting. The old thermocouple had developed a hole in the tip and the tip was discolored when I removed it.
I checked the pilot today and it went off sometime today or yesterday. I noticed that the new thermocouple developed a hole in the tip and the tip was also somewhat discolored.
I relighted the pilot and it appears to still work fine.
Is the thermocouple suppose to develop a hole in the tip after being exposed to the pilot flame for a few days?
Edit: I have removed the thermocouple and it is not a hole, but just discoloring. I have cleaned the tip and reinstalled it.