Topics: All categories in the pool
1: What must be done to all doors and access points in duct work going through a mechanical room?
- Must be hindged
- Must be screwed shut
- Must be sealed and gasketed
- All of the above
2: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 33
- 22
- 18
- 50
3: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
- does not require a pressure-limiting device
- shall have a pressure limiting device installed on the high side of the system
- shall have a pressure limiting device and a pressure relief valve installed
- shall be inspected by the Boiler of Inspectors bi-annually
4: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 660 lbs
- 55 lbs
- 550 lbs
- 330 lbs.
5: How many refrigerant classifications are there for toxicity?
- 3
- 1
- 2
- 5
6: What is the temperature that a liquid and a vapor can exist in equilibrium called?
- Dry bulb temperature
- Saturated temperature
- Critical temperature
- Wet bulb temperature
7: Where can 50/50 solder be used on?
- suction line
- liquid line
- discharge line
- none of the above
8: Ammonia vaporization takes place at what temperature?
- -32F
- -28F
- -460F
- -110F
9: If the compression ratio on a centrifugal compressor rises too high, the compressor will stop pumping and make a loud sound commonly referred to as a
- splurge
- merge
- purge
- surge
10: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- “UM” and “UV”
- “UV”
- “U” or “UM”
- “UL”
11: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- The rate of conduction
- 1 Kelvin
- 1 Therm
- 1 BTU
12: Oils, classified as to source, are
- naphthalene, mixed, and paraffin
- animal, vegetable, and mineral
- naphthalene, paraffin, and castor
- animal, vegetable, and castor
13: Which of the following is an example of an azeotropic refrigerant?
- R-134A
- R-404A
- R-410A
- R-500
14: What is a Category "D" fluid?
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and design temperature is between -20F to 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily contact
- Any fluid that exceeds 150 psig and has design temperature of over 366F
- A typical refrigerant used on newer air conditioning and heat pump ssytems
15: Liquid line filter-driers on a 410A system must be rated for no less than
- 600 psig
- 1000 psig
- 200 psig
- 400 psig
16: The two float-type metering devices are the
- liquid float and the low-side float
- vapor float and the low-side float.
- high-side float and the low-side float
- liquid float and the vapor float
17: What is Trichlorotrifluoromethane?
- R-113
- R-12
- R-13
- R-11
18: What does an anemometer measure?
- amperage
- temperature
- voltage
- velocity
19: When testing systems using non-positive displacement compressors, the entire system shall be considered for test purposes as the low side.
- True
- False
20: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
21: Electricity involves the movement of electrons in atoms
- True
- False
22: The proper location for an oil separator is between the
- evaporator and compressor
- compressor and condenser
- receiver and metering device
- condenser and receiver
23: What should never be used in pressure testing refrigeration systems?
- Oxygen
- Compressed air
- Nitrogen
- Both a and b
24: "E" represents _____ in the Watt's law formula.
- watts
- voltage
- reactance
- amperage
25: In a motor, an internal overload might open if
- there was a high pressure refrigerant was used for a low pressure system.
- there's an open start winding
- there's an excess current draw through the motor
- there's a direct short