Topics: All categories in the pool
1: Which of the following is a drop-in for R-22
- R-410A
- R-134A
- R407C
- None of the above
2: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- 1 Kelvin
- 1 Therm
- 1 BTU
- The rate of conduction
3: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
- 1.2
- 1.5
- 2.2
- 1
4: What refrigerant doesn't have to be classified?
- R-134A
- R-717
- R-422A
- R-718
5: R-11 has the greatest corrosive effect on
- Magnesium
- Copper
- Aluminum
- Bronze
6: Which of the following most closely represents the concentration of Li-Br in a absorption system?
- 60% Li-Br, 40% distilled water
- 50% Li-Br, 50% tap water
- 40% Li-Br, 60% tap water
- 40% Li-Br, 60% distilled water
7: What would be the classification for Stop & Shop grocery store?
- Instituional
- Large mercantile
- Industrial
- Place of assembly
8: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8
- the liquid side of the system
- high side of the system
- low side of the system
- the vapor side of the system
9: A secondary coolant is defined as
- any refrigerant direcly in contact with the cooling space for process cooling
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
- a low temperature refrigerant used for cascading systems
10: A single pole-double throw switch uses how many wires?(excluding the ground)
- 5
- 3
- 2
- 4
11: What is not a requirement of a class T machine room?
- fire hose connection to the building fire protection system
- automatic ventilation
- self-closing doors
- tight fitting doors
12: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Air
- Heat
- Electricity
- Oil
13: A micron is
- one millonths of a micrometer
- one thousandths of a millimeter
- one millonths of a centimeter
- a larger unit of measurement than Hg
14: How many forces operate a thermostatic expansion valve?
- 2
- 3
- 4
- 1
15: The location of a thermal bulb of a TXV affects
- subcooling
- the amount of liquid refrigerant in the evaporator
- the amount of liquid in the condenser.
- the amount of liquid returning to the compressor
16: Before you change the type of refrigerant in a refrigeration system, what three things must be done?
- Nothing must be done
- Make sure its compatible, notify owner, and notify AHJ.
- you can never change refrigerants
- Place sign, check for leaks, and insulate suction line
17: Stop valves shall not be permitted between the system and the
- condenser
- service valve
- relief valve
- bleed valve
18: What must be done if refrigeration lines pass through a concrete floor?
- installed through a pipe casing
- insulated
- leak checked
- moisture barrier
19: Heat cannot of itself, pass from a
- cold to a warmer body
- warm to a colder body
- state of hot energy to a state of cold energy
- None of the above
20: What type of relief valve is used on low pressure centrifugal compressor systems?
- Spring-loaded relief valve
- Rupture disc
- Purge relief
- None of the above
21: 746 watts is equal to
- 1 hp
- 10 hp
- Pi
- 100 hp
22: A tachometer is an instrument used to measure
- speed
- static pressure
- RPM
- air velocity
23: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
24: What is absolute humidity?
- the amount of moisture in the air per one pound of 50% RH air
- the amount of moisture in the air in grains of cubic feet of volume
- the amount of moisture in the air in grains of square feet of volume
- none of the above
25: What effect does the temperature of air have on humidity?
- warmer air holds more moisture then cooler air
- cooler air holds more moisture then warmer air
- air has no effect of humidity
- none of the above