Topics: All categories in the pool
1: Give an example of a secondary coolant?
- R-12
- R-718
- R-410A
- R-717
2: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- 2F difference
- a ling psychrometer doesn't have two theremometers.
- far apart or greater difference
- nearly the same
3: Which refrigerant class listed below is the most flammable?
- B2
- A3
- A2
- C3
4: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
- 20 amps
- 15 amps
- 10 amps
- 5 amps
5: Where would the EPR valve be located on a multiple evaporator system?
- outlet of the liquid line
- outlet of low temperature evaporator
- outlet of high temperature evaporator
- inlet of the low temperature evaporator.
6: All electrical work done on refrigeration systems must comply with
- Department of Energy
- OSHA
- NEC and Massachusetts Modifications
- ASHREA-15 Section 9.2.1
7: When using nitrogen for brazing, the pressure should be:
- 50-100 psig
- Slightly below atmospheric
- 125 psig
- Very low
8: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or more
- vessels of 3 cubic feet or less
- vessels of 10 cubic feet or less
- vessels of 3 cubic feet or more
9: The freezing point of water at sea level is?
- -10C
- 32F
- 32C
- 0F
10: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8
- low side of the system
- the liquid side of the system
- the vapor side of the system
- high side of the system
11: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- 1 BTU
- 1 Kelvin
- 1 Therm
- The rate of conduction
12: Large mercantile occupancy is
- a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
- a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise
- a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
13: What is considered a cooling agent?
- any liquid used for the transmission of heat when vaporization occurs
- any liquid used for the transmission of heat without vaporization
- any liquid used for the transmission of heat when condensation occur
- any liquid used for the transmission of heat without condensation
14: What is specific heat?
- measured heat
- heat required to raise the temperature of 1lb of a substance 1 degree
- the specific heat required to change the state of one cubic foot of air to steam
- none of the above
15: A hissing noise at the expansion valve is a good indication that
- expansion valve is oversized
- nothing is passing thru
- gas is passing thru it
- liquid is passing thru it
16: The difference between saturated liquid and saturated vapor is
- volume
- temperature
- heat
- pressure
17: What device should be used on low-temperature freezers?
- discharge muffler
- high capacity TXV
- oil separator
- hot-gas by-pass
18: The actual expansion curve of compression follows most nearly which one of the following curves?
- Volume Temperature
- Isothermal
- Adiabatic
- Pressure Temperature
19: A High-Probablity system
- is such that a leak of refrigerant from failed connections will enter the unoccupied space
- is such that a leak of refrigerant from failed connections will enter the occupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is a system highly likely to leak from a failed connection or component of such system
20: Single compound Refrigerants are classified by what two criteria?
- Flammability and temperature range
- Weight and color
- Temperature range and hazardousness
- Flammability and toxicity
21: A premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space such as auditoriums, ballrooms, classrooms, passenger depots, restaurants, and theaters is considered a(n)
- institutional occupancy
- illegal occupancy
- public assembly occupancy
- commercial occupancy
22: Which of the following controllers would you expect to be most sensitive to temperature changes?
- immersion controller
- aquastat
- low voltage t-stat
- line voltage t-stat
23: A start capacitor is wired in _____ with the start windings.
- series
- parallel
- series-parallel
- junction
24: An example of an "Expendable Refrigerant" is
- liquid oxygen
- lithium bromide
- ammonia
- liquid nitrogen
25: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.
- 100%
- 75%
- 90%
- 80%