When is the sensor preheating option on the HM70 probes needed?

The sensor preheating option should be selected when there is a risk of condensation. When transferring the probe from normal room conditions into warm and humid conditions, it is likely that the probe head temperature will be below the chamber dewpoint, resulting in condensed water on the sensor. Sensor preheat prevents this unwanted situation. In sensor preheat mode, the sensor is heated to a temperature of approximately +100 °C for up to 4 minutes. This raises the temperature of the sensor above the dewpoint temperature of the process, thereby preventing condensation.