Aspirator: Description and Operation

In order for the in-vehicle sensor to operate accurately, an aspirator has been incorporated into the system, which will cause in vehicle air to be drawn over the sensor. The aspirator is mounted on the heater case. Due to the design of the aspirator, a small amount of air from the module assembly will cause a slight vacuum effect at the end of the aspirator. The in-vehicle sensor is connected by a small hose to the end of the aspirator. Once vacuum is created in-vehicle air will be drawn over the sensor grille, allowing the sensor to signal the control head to adjust the in-vehicle temperature to the temperature range selected. The drawn air is then expelled back into the passenger compartment. If the hose sensor between the sensor and the aspirator is missing, disconnected, or kinked, passenger compartment air will not be drawn over the sensor and the system will not maintain the selected temperature.