NEM Chapter 516, Refrigeration System Requirements

Question 1

Ship’s service air condition units are typically ___ cooled

Answer 1

Raw water cooled

Question 2

New ship’s a/c units shall use refrigerant ___

Answer 2

R-134a

Question 3

Existing R-12 ship’s service a/c units shall be replaced by R-134a units at the ___

Answer 3

Earliest opportunity

Question 4

Existing R-22 ship’s stores refrigeration units shall be replaced by R-134a units at the ___

Answer 4

End of their service life

Question 5

A reach-in chill and freeze box are considered self-contained equipment if the internal gross volume is less than ___

Answer 5

100 cubic feet each

Question 6

New self-contained equipment shall use refrigerants that are ____

Answer 6

HFC, non-ozone depleting, have low global warming potential, and are classified as Safety Group A1 in ASHRAE 34

Question 7

Refrigerants must be listed in ___ as an acceptable refrigerant under the EPA SNAP program

Answer 7

40 CFR 82

Question 8

Represents how much a given mass of chemical contributes to ozone depletion over a given time period compared to the same mass of R-12

Answer 8

Ozone Depletion Potential

Question 9

ODP

Answer 9

Ozone Depletion Potential

Question 10

R-12 ODP is defined as ___

Answer 10

1.0

Question 11

Represents how much a given mass of chemical contributes to global warming over a given time period compared to the same mass of carbon dioxide

Answer 11

Global Warming Potential

Question 12

GWP

Answer 12

Global Warming Potential

Question 13

Carbon dioxide’s GWP is defined as ___

Answer 13

1.0

Question 14

___ oil cannot be used in the HFC refrigerant system

Answer 14

Traditional mineral

Question 15

The use of ___ is required to ensure adequate lubrication and oil return to the compressor in an HFC refrigerant system

Answer 15

Polyolester lubricant (POE)

Question 16

The POE oil is supplied in several viscosities

Answer 16

32 cSt
46 cSt
68 cSt
100 cSt

Question 17

For CG applications, an ISO viscosity grade of ___ should be used. If this grade is not available, an ISO viscosity grade of ___ may be used

Answer 17

68

46

Question 18

Upon receipt of a replacement compressor the installing activity shall drain the oil from the compressor and flush the compressor with ___ to alleviate the possibility of ____

Answer 18

Approved oil

Mixing oils when installed in the system

Question 19

Standard brazing practice is to follow ___ or ___

Answer 19

Commercial practice

US Navy practice

Question 20

Brazing requirements shall be modified as necessary to ensure copper to copper joints are brazed using a ___

Answer 20

Fed Spec QQ-B-654A, BAg5

Question 21

Brazing requirements shall be modified as necessary to ensure stainless steel to copper joints are brazed using ___

Answer 21

Fed Spec QQ-B-654A, Grade V alloy

Question 22

Freezer shall be set to operate at ___, cut off at ___ and cut on at ___

Answer 22

0°F
-3°F ± 1°F
0°F ± 1°F

Question 23

Refrigerator shall be set to operate at ___, cut off at ___ and cut on at ___

Answer 23

33°F
33°F + 1°/0°F
35°F ± 1°F