Water temp reading on wall mounted control reads over 100 degrees, but the temp on the Mastertemp panel reads 45 which is correct. I can't get the calibration feature to go below 100 on the controls. I checked the thermistor with a new one and they both read the same. The heater will run when I set the set point to over 100, but shuts off when the two or three degrees raise the control panel reading.

Pool & Spa - Pentair - Mastertemp Heater