It's the one on the outlet of my HLT, screwed into the tee in a Kal-style build. It jumps around by 3 or 4 degrees all the time now, going from say 149 to 152 to 150 to 153 to 151 to 149 etc. It's not the cable or the PID because plugging a different PT100 (like the one in my BK) into the same cable does not jump around.
What can go wrong with the RTD itself that might cause this, and do I need to get a new one? It's only about 3 months old. Thanks!