Academic Catalog


Foothill College Course Outline of Record

Foothill College Course Outline of Record
Heading Value
Effective Term: Summer 2021
Units: 5
Hours: 37 lecture, 86 laboratory per quarter (123 total per quarter)
Prerequisite: Per California Code of Regulations, this course is limited to students admitted to the Plumbing & Pipefitting Apprenticeship Program.
Degree & Credit Status: Degree-Applicable Credit Course
Foothill GE: Non-GE
Transferable: None
Grade Type: Letter Grade (Request for Pass/No Pass)
Repeatability: Not Repeatable

Student Learning Outcomes

  • 2- Explain the difference between electric defrost and hot gas defrost.
  • 1- Explain why we have pump down systems and their benefits


Second-year course of the Plumber, Pipefitter & Service Technician Apprenticeship Program. Provides the student with a working knowledge of the fundamentals of oil return and oil separators, electric and hot gas exhaust, multi-stage compressor systems and pump down systems.

Course Objectives

The student will be able to:
A. Describe hot gas defrost and demonstrate how it works.
B. Explain elect defrost and demonstrate how it works.
C. Explain how a oil separator works.
D. Explain why we have pump down systems.
E. Describe the importance of oil return.

Course Content

A. Hot Gas Defrost
1. How it is piped around a evaporator coil
2. Where hot gas comes from and how it is diverted
B. Elect Defrost
1. Understanding how a defrost time clock works, and how to set it up
2. Testing the elect heat strips in a coil
C. Oil Separator
1. Understanding how it works and if it is working correctly
2. Define how it is piped into a system
D. Pump Down Systems
1. Draw a pump down system out
2. Define why we have a pump down system and the benefits
E. Oil Return
1. Understanding how to pipe a system for correct oil return
2. Making sure there is enough refrigerant velocity for oil return

Lab Content

Students will work individually and in teams on practical problems in:
A. Oil piping return diagrams
B. Test elect defrost timer operation and draw it out
C. Run test hot gas operation
D. Test oil separator for correct operation
E. Run test pump down systems

Special Facilities and/or Equipment

A. Lecture and laboratory classrooms with chalkboard.
B. Hampton refrigeration trainer in shop.

Method(s) of Evaluation

Written examination
Hands-on Hampton trainer
Group and classroom participation

Method(s) of Instruction

Lectures and classroom discussions on market refrigeration
Laboratory (hands-on) refrigeration Hampton trainer
Demonstrations in front of classroom

Representative Text(s) and Other Materials

International Pipe Trades Joint Training Committee, Inc.. HVACR Student Set. 2008.

Although this text is older than the suggested "5 years or newer" standard, it remains a seminal text in this area of study.

Types and/or Examples of Required Reading, Writing, and Outside of Class Assignments

A. Readings from HVACR Student Set:
1. HVACR Training Manual, Unit 25, Special Refrigeration System Components
B. Writing assignments include homework from:
1. HVACR Training Manual, Unit 25, Special Refrigeration System Components


Plumbing OR Steamfitting OR Air Conditioning, Refrigeration, Heating