NATE Industry Competency Exam: Commercial Refrigeration Questions And Answers | Latest Updated | 2025/2026

NATE Industry Competency Exam: Commercial Refrigeration Questions And Answers | Latest Updated | 2025/2026 With the condensing pressure and compressor speed remaining constant, a decrease in suction pressure will cause a(n): a. Decrease in compressor capacity and decrease in current. b. Increase in compressor capacity and decrease in current. c. Increase in compressor capacity and increase in current. d. Decrease in compressor capacity and increase in current. - answer-D An indication of non-condensable gas in a refrigeration system is significantly: a. Lower-than-normal suction pressures. b. higher-than-normal suction pressures. c. Lower-than-normal head pressures. d. higher-than-normal head pressures. - answer-D An automatic expansion valve controls refrigerant flow to an evaporator by maintaining a constant: a. Suction pressure. b. Pressure differential across the valve port. c. Liquid line pressure. d. Superheat. - answer-AWhat is the approximate compression ratio of a compressor operating at 35 psig suction pressure and 135 psig discharge pressure? a. 1:03. b. 3:01. c. 1:04. d. 4:01. - answer-B The BTUs rejected at the condenser are always greater than the heat absorbed in the evaporator because: a. The condenser is mounted outside with restricted airflow. b. Of the high temperature of the discharge vapor and length of the discharge line. c. Of the inefficiency of the condenser and pressure drop in the discharge line. d. Of the heat of compression in the compressor. - answer-D A unit cooler is inspected and found to be completely iced up. The heaters and defrost timer are found to be working properly. A technician should: a. Adjust the defrost termination switch to a higher temperature setting. b. Adjust the thermostatic expansion valve to a higher superheat setting. c. Clear all of the ice from the coil and find out why the coil is frosted. d. Increase the frequency of the defrost cycle. - answer-A