Air Conditioning Repair Certification (ETI) Practice Exam 2025 - Free Air Conditioning Repair Practice Questions and Study Guide

The correct answer pertains to what the automatic expansion valve is specifically designed to maintain, which is the pressure at the evaporator outlet. This type of expansion valve controls the flow of refrigerant into the evaporator coil based on the pressure in that section of the system.

When the pressure at the evaporator outlet decreases, the automatic expansion valve will open wider to allow more refrigerant to flow into the evaporator, maintaining the pressure at the desired set point. This operation helps ensure efficient cooling and proper heat exchange within the system.

While sensor bulb temperature and constant evaporator temperature are important concepts in HVAC systems, they are not the primary focus of the automatic expansion valve's function. Also, although sensor bulb pressure relates to the overall system, it does not directly represent the specific role of the automatic expansion valve in regulating the outlet pressure.

Understanding the role of the automatic expansion valve is crucial for diagnosing and repairing HVAC systems, as it is a key component in maintaining the efficiency and effectiveness of the cooling process.