NATE Exam: AC & HP Questions and Answers

a (Centrifugal) - ANSWER-Which of the following compressors are considered a dynamic compressor? a. Centrifugal b. Reciprocating d. Rotary c. Scroll b (Superheated vapor / sub cooled liquid) - ANSWER-What is the condition of the refrigerant as it enters and leaves the condensing coil of a typical light commercial HVAC system? a. Vapor / liquid b. Superheated vapor / sub cooled liquid c. Saturated vapor / saturated liquid d. Hot gas / cool liquid b (Thermal expansion valve) - ANSWER-Which one of the following are considered the best metering device of the industry? a. Capillary tube b. Thermal expansion valve d. Constant pressure expansion valve c. Electronic expansion valve b (POE. Newer refrigerant systems today using R-134a and R-410a use a synthetic Polyester POE oil. Older refrigeration systems using R-12, R-502, and R-22 use a mineral based oil.) - ANSWER-Which of the following types of refrigeration oil would you expect to find in a typical commercial R-134a freezer? a. Mineral 150 b. POE c. AB d. Mineral 300 b (Compressor discharge / compressor suction) - ANSWER-Where does the small single port tube and the larger middle port tube go on a typical residential or light commercial reversing valve? a. Inlet outdoor coil / inlet indoor coil b. Compressor discharge / compressor suction c. Compressor suction / compressor discharge c. Outlet indoor coil / outlet outdoor coil