Unit 1
5. Molecular motion stops at
– 460°F.
2. Solid, liquid, and gas are the most common
states of matter
6. A ___________ can remove any type of foreign matter that enters a refrigeration system.
filter drier
12. The safest overall rating with respect to both toxicity and flammability is
A1
2. When charging a system with vapor refrigerant, what can be done to increase the pressure in the refrigerant tank?
Place the tank in a bath of warm water
9. An increase in sensible heat causes
a higher thermometer reading.
3. In what direction does a solid exert force?
Downward
14. The most accurate type of gauge for measuring a deep vacuum is a
digital micron gauge
21. The term used to describe the process of removing refrigerant from a system and storing it without testing or processing it is
recovering
3. As a system is charged with vapor refrigerant, the refrigerant tank will likely
experience a pressure drop and a temperature drop.
10. Latent heat causes
a change of state
5. Vapor exerts pressure in what direction?
Outward, upward, and downward
18. Proper maintenance for a vacuum pump would include which of the following?
Changing the oil as often as necessary
25. Which type of EPA Section 608 certification is required to work on small appliances?
Type I
8. The term “blend” refers to a refrigerant that
. is made up of two or more different refrigerants.
17. To change from psig to psia, you must
add 14.696 to psig.
#16 What are the two types of energy most frequently used or considered in this industry?
Solar and fossil fuels
19. When a deep vacuum is reached (500 microns), the system is valved off and observed for 10 to 15 minutes. A rise in pressure could indicate which of the following?
There may be a leak or the presence of air and/or moisture
30. A DOT-approved refrigerant recovery cylinder is color-coded
gray with a yellow top.
9. If the components of a binary refrigerant blend have saturation temperatures of 35°F and 42°F at a pressure of 120 psig, what is the approximate temperature glide associated with this refrigerant?
7°F
#21 A barometer is used to measure
atmospheric pressure.
21. What unit of energy does the power company charge the consumer for?
Kilowatt-hour
21. An oily dust spot on a condenser or evaporator coil could indicate
a refrigerant leak.
33. The Montreal Protocol is best described as a
treaty or agreement among nations to address ozone depletion.
11. Which of the following statements is true regarding azeotropes and zeotropes?
They are both refrigerant blends