How do you recalibrate a COMARK PDT300?

To recalibrate a COMARK PDT300, first ensure the device is clean and at room temperature. Turn on the unit and navigate to the calibration menu, usually found in the settings. Then, follow the prompts to perform a calibration using either standard calibration points or by immersing the probe in known temperature references, such as ice water or boiling water. After calibration, save the settings and verify accuracy with a secondary reference if needed.