NATE Final Exam #1 correctly answered latest 2023

NATE Final Exam #1 correctly answered latest 2023Generally, vibration eliminators in piping should be installed: A: At a 45 degree angle B: At a 90 degree angle C: Perpendicular to the compressor crankshaft D: Parallel to the compressor crankshaft D: Parallel to the compressor crankshaft If you purchased ten filter-driers for $100.00, what was the price of each filter-drier? A: $100.00 B: $10.00 C: $1.00 D: $1.10 B: $10.00 Which of the following jobs requires safety glasses? A: Driving a vehicle B: Extending a ladder C: Brazing D: Pulling thermostat wire C: Brazing Which of the following instruments would typically be used to measure a vacuum? A: Micron gauge B: Thermostat C: Anemometer D: Differential pressure gauge A: Micron gauge ASHRAE Standard 34 deals with: A: Carbon monoxide safety levels B: Refrigerant quality C: Equipment room ventilation and alarms D: Refrigerant toxicity and flammability D: Refrigerant toxicity and flammability ANSI/ASHRAE 34 published in 2001 and entitled "Designation and Safety Classification of Refrigerants". • Class A signifies refrigerants for which toxicity has not been identified at concentrations less than or equal to 400 ppm; • Class B signifies refrigerants for which there is evidence of toxicity at concentrations below 400 ppm. • Class 1 indicates refrigerants that do not show flame propagation when tested in air at 21°C and 101 kPa; • Class 2 indicates refrigerants having a lower flammability limit of more than 0.10 kg/m3 at 21°C and 101 kPa and a heat of combustion of less than 19 kJ/kg; • Class 3 indicates refrigerants that are highly flammable as defined by a lower flammability limit of less than or equal to 0.10 kg/m3 at 21°C and 101 kPa or a heat of combustion greater than or equal to 19 kJ/kg. What control would you use on a capillary tube or automatic expansion valve system to maintain the desired temperature? A: Dual pressure control B: High pressure control C: Thermostatic temperature control D: Low pressure control C: Thermostatic temperature control The total heat contained in any substance is obtained by adding together its: A: Radiant and specific heat B: Latent and sensible heat C: Radiant and sensible heat D: Specific and latent heat B: Latent and sensible heat An outdoor air conditioning condensing unit should not be located: A: In the sun B: On the side of the house C: Within 5 feet of a hose bib connection D: Where any objects or obstructions are within 5 feet of the condenser fan D: Where any objects or obstructions are within 5 feet of the condenser fan An outdoor air conditioning condensing unit should not be located: A: Under an overhang where water may drain onto it B: Within 4 feet of a hose bib connection C: Within 3 feet of an electrical disconnect D: All of the above A: Under an overhang where water may drain onto it A thermostat should be mounted: A: Approximately 5 feet above the floor B: Level C: On an inside wall D: All of the above D: All of the above As the pressure on a liquid rises, the temperature at which the liquid will boil: A: Varies B: Remains the same C: Increases D: Decreases C: Increases A voltmeter is connected to a circuit: A: In series B: In parallel C: Crossover D: Delta B: In parallel Pressure relief valves are not to be piped: A: In parallel B: In series C: Facing up D: Within 12" of a wall B: In series Which of the following is typically covered by local codes? A: Refrigerant type B: Maximum length of refrigerant lines C: Location of condensing unit disconnect D: Location of liquid and suction line service valves C: Location of condensing unit disconnect Hard drawn ACR tubing may not be used: A: In combination with soft drawn ACR tubing B: Without first annealing the tubing C: With a swedge joint D: On residential applications C: With a swedge joint Which of the following oils is the most hygroscopic? A: POE oil B: Mineral oil C: Vegetable oil D: Vacuum pump oil A: POE oil Highly hygroscopic oils must be kept in: A: Metal or glass containers B: Tightly capped plastic containers C: An area out of direct sunlight D: A refrigerated space 50 degrees or cooler A: Metal or glass containers The purpose of technician certification is to: A: Raise the competency level of technicians B: Decrease the number of poorly installed and improperly serviced systems C: Help consumers choose well-trained technicians D: All of the above D: All of the above The purpose of converting psig to psia prior to calculating the compression ratio of a system is to: A: Make the answer come out as a positive number if the low side pressure is in a vacuum B: Make sure the answer is never negative C: Make the answer mathematically correct D: Allow for easy conversion to the metric system C: Make the answer mathematically correct As a warm air furnace raises the temperature of the air in a structure, the relative humidity of the space will: A: Increase B: Decrease C: Increase by the square of the change in temperature D: Remain the same B: Decrease ACR soft copper tubing comes in: A: 20 foot lengths B: 30 foot sealed rolls C: 50 foot rolls D: 50 foot sealed rolls D: 50 foot sealed rolls Typical ACR copper tubing flares are: A: Double flares B: 33 degree flares C: 45 degree flares D: 60 degree flares C: 45 degree flares Customers generally trust technicians who: A: Look them straight in the eye during conversations B: Genuinely listen to the customer's concerns C: Provide them with accurate information and options D: All of the above are correct D: All of the above are correct What amount of oxygen is normally contained in air? A: 10% B: 15% C: 21% D: 25% C: 21% The "critical temperature" and pressure of a refrigerant is: A: The conditions above which a refrigerant gas cannot be condensed into a liquid B: The conditions below which a refrigerant cannot be vaporized to a gas C: The conditions where even if a change of state were to occur, no latent heat exists D: The pressure at which no heat exists in the refrigerant therefore the temperature is absolute zero A: The conditions above which a refrigerant gas cannot be condensed into a liquid Refrigerant cylinders should never be filled to over: A: 50% B: 65% C: 80% D: 90% C: 80% Which of the following gases should never be used to pressure test for leaks? A: Nitrogen B: Oxygen C: Carbon dioxide D: None of these should be used for pressure testing B: Oxygen What is the nominal operating wattage of a one-quarter horsepower electric motor? A: 186 watts B: 100 watts C: 46 watts D: 373 watts A: 186 watts The electrical resistance of a thermistor _________ with a temperature increase. A: increases B: decreases C: remains unchanged D: varies by the 10th power B: decreases Removing refrigerant from a system and storing it in a cylinder without performing any testing or processing is called: A: Recycling B: Reclaiming C: Recovering D: Restoring C: Recovering