4. Briefly describe the following in main refrigeration plants:
(a) How can sea temperature restrict plant operation?
(b) How are the limitations in (a) overcome?
(c) How does short cycling occur?
(d) How is short cycling avoided?
Class 3
1. Sketch a simple refrigerant cycle of compression type plant. What kind of gas is commonly used in this type of plant?
a. A liquid
b. A gas
2. Describe the basic refrigerant circuit for a compression type plant. What kind of gas is commonly used in this type of plant?
3. State the reasons why Freon 12 is a popular refrigerant gas.
4. Explain why the refrigerant gas in a compression type domestic refrigeration plant is passed through a condenser after begin compressed
Test example 8
Class 1
1. Describe, with sketches, an inert gas system using gas from the main uptakes. Explain:
a. The scrubbing process and its purpose
b. Safety devices
2. Compare the advantages and the disadvantages of the following fixed fire extinguishing systems:
a. High-pressure water spray
b. Carbon dioxide smothering
c. Chemical foam smothering