NATE Exam Bundle Graded A+

Low airflow over a residential split system air conditioning evaporator can cause A: Liquid flood-back to the compressor B: A decrease in compression ratio C: An increase in suction line superheat D: Oil logging in the evaporator - A: Liquid flood-back to the compressor Which of the following i...

Which of the following factors affects a customer's level of comfort? a. Air movement b. Humidity c. Temperature d. All of the above - d (All of the above: air movement, humidity, temperature) A cooling load calculation estimates the sensible heat gain of a structure. The maximum sensible cap...

Charging a heat pump with refrigerant is best accomplished in the _______ mode. A: Heating mode B: Cooling mode C: Defrost mode D: Emergency heating mode - B: Cooling mode Heat pumps can provide both heating in the winter and cooling in the summer. In which mode is the heat pump more efficient...

A system is supplied from the factory with charge of 5 pounds 10 ounces for a 15 foot line set. The line set is 25 feet long. The manufacturer's instruction sheet specifies 0.6 ounces of refrigeration to be added for each added foot of refrigerant line set length. What is the total refrigerant ch...

What electro-mechanical control would you use on a cap tube or automatic expansion valve system to maintain the space temperature? - C: A thermostatic control Open motors are designed to operate at a given temperature rise as indicated on the motor nameplate. What does this mean? - A: indicates t...

Since 1992, the United States Department of Energy has required that all furnaces sold and installed from that date on must have an AFUE of no less than: A: 70% B: 75% C: 78% D: 80% - C: 78% Many pre-1992 furnaces have efficiencies around _______. A: 10% B: 40% C: 60% D: 80% - C: 60% Toda...