Vapor Cycle Systems

Question 1

What type of refrigerant do we use now in coast guard aviation

Answer 1

R134a

Question 2

Safety warnings and precautions for vapor cycle systems

Answer 2

Always wear face shield and gloves

Vapor systems are pressurized even when turned off

Don’t mix refrigerants or refrigerant oils

Use only comparable refrigerants

Freon must be cycled through a cycling unit to relieve pressure before lines can be loosened

Question 3

Pressurizes the vaporized refrigerant to heat it up and push it through the system

Answer 3

Compressor

Question 4

The blower fan blows ambient air across metal fins of this item to cool and condense the hot high pressure refrigerant back into liquid state

Answer 4

Condenser

Question 5

Electrically de-energizes the compressor in the event of high pressure to prevent system damage

Answer 5

High pressure switch

Question 6

Filters moisture and contaminates in the refrigerant

Answer 6

Filter/ dryer

Question 7

Refrigerant reservoir

Answer 7

Receiver

Question 8

Provides a visual check of refrigerant levels

Answer 8

Sight gauge

Question 9

Sprays pressurized liquid into the coils of the evaporator, the sudden expansion results in pressure drop.

Answer 9

Expansion valve

Question 10

Blower fans blow cabin air across the metal fins of this raising the refrigerant temperature from about thirty degrees to 40 which then is circulated through the cabin ductwork

Answer 10

Evaporator

Question 11

De-energizes the system in the event of low pressure to prevent system damage

Answer 11

Low pressure switch

Question 12

Prevents evaporator freeze up by allowing hot refrigerant to flow to the low pressure super cool system through a variable orifice

Answer 12

Capacity regulator valve

Question 13

Allows refrigerant to be added into the system.

Allows servicing through this

Answer 13

Servicing valve / servicing port

Question 14

Circulates air through the evaporator and through air ducts

Answer 14

Blower fans