The temperature sensor used in HVAC is mainly the evaporator temperature sensor, which uses NTC (Negative Temperature Coefficient) negative temperature counting thermistor, which means that when the temperature drops, its resistance value increases and the current changes. , this signal is collected and processed by the temperature control unit (such as thermostat, control panel), and sends a signal to control the closing of the compressor clutch to achieve temperature control and prevent the evaporator from freezing.

Temperature sensor for automobile air conditioner

Temperature sensors must have good stability, sensitivity and durability. However, the evaporator temperature sensor is generally placed at a certain distance from the evaporator surface. Some sensors are also placed inside the evaporator fins, which makes the temperature collection more sensitive and accurate. To test the sensitivity and accuracy of the sensor, the resistance value must be measured from -30C to 85C, one set of data is measured every 5C, one set of data is measured every 1 between -10C and 10C, and one set of data is measured every 0.1 between -1C and 6C. C measures a set of data and then draws a T-R curve as a basis for judging the quality of the sensor.