7.11 AC_R

Question 1

Sensible Heat

Answer 1

Heat added (or removed) to a substance that causes the temperature to rise (or fall)

Question 2

Latent Heat

Answer 2

Heat added or removed that does not cause a change in temperature but accomplishes a change in state

Question 3

Refrigerant

Answer 3

Medium employed as the heat absorber or cooling agent that is affected by heat, temperature, and pressure in a manner similar to water. Refrigerant selection is based on low boiling point and other desirable characteristics.

Question 4

Synthesized Refrigerants

Answer 4

Chemists found that by juggling atoms of hydrocarbons almost any type of refrigerant needed for a specific use can be synthesized.

Question 5

Halocarbon Refrigerants

Answer 5

Colorless and practically odorless in low concentrations, they are all heavier than air but have different specific volumes, boiling points, and various pressures at which they liquefy under ordinary temperatures.

Types of refrigerants:
R-12
R-114
R-134a

Question 6

Shipboard Applications of A/C

Answer 6

Installed to cool spaces where operation of equipment, personnel efficiency, health, or safety could be adversely affected by heat or high humidity.

Ammunition storage and handling rooms
Electronic equipment and control spaces
Hospital areas, living, messing, and office spaces

Question 7

Shipboard Applications of Refrigeration systems

Answer 7

Used aboard naval ships include the following (systems containing Freon are colored dark purple)

Refrigerated ship stores
Air conditioning units
Drinking water cooling
Self-contained refrigeration equipment

Question 8

Direct System

Answer 8

Circulates the refrigerant through cooling coils that are located in, or adjacent to, the spaces cooled

Question 9

Indirect System

Answer 9

Circulates refrigerant to a heat exchanger or water chiller that cools fresh water (chill water). The cooled fresh water is then circulated to cooling coils in throughout the ship.

Question 10

Record Keeping

Answer 10

Logs are kept for equipment with 50 lbs of refrigerant or more.
Inspected monthly by the CHENG
Kept onboard for 3 years

Question 11

Refrigeration Safety

Answer 11

Always wear goggles while handling
Keep caps on cylinders when not in use
Never lift a cylinder with a sling in the cylinder cap
Use care when handling
Never fill cylinders above 80 %
Store cylinders in a cool space
Secure cylinders in stowage racks
Personnel must wear protective clothing
No Hot Work is permitted while working with refrigerants
Avoid rubbing or irritating the eyes if in contact