Course Title:
Course Number:
|
Introduction to the Refrigeration
Cycle: Part 2
AC/R-2 |
| |
This course
is a continuation of Part 1 I Intro. To Refrigeration Cycle,
focusing on high temperature applications including: compressors,
condensers, evaporators, metering devices, accessory components,
compressor capacity controls, balanced system operation, and
pressure-temperature charts. |
| Course
Outline: |
Download/print this course outline |
| DAY
1 SUBJECT: |
Introduction to the Troubleshooting
Chart and System Operating Components |
| GOAL: |
Demonstrate how
an entire air condition system is affected by a single problem
and how it can be diagnosed by the troubleshooting chart.
Show how the TXV and Cap react to over charge and under charge.
|
| OBJECTIVES:
|
Understand
the terminology on the troubleshooting char and terminology
used in the HVAC/R trade.
Use the chart to diagnose problems in a typical A/C system
What happen to each component under these conditions
Note differences between charging valves and the service valve
|
| SUBJECT CONTENTS:
|
Troubleshooting
chart instructions
Terminology used on the chart
Temp changes across an air cool condenser
Temp changes across a DX fan coil
Normal pressure ranges in an A/C system
Sub cooling temp
Superheat temp
Terminology used on components
TXV, captubes
Safety when installing & removing service gauges
Identify different types of refrigerant valves and the use
Use of different thermometers
Review of shop safety |
METHODS/
TECHNIQUES: |
Handout on troubleshooting
chart
Refrigeration & A/C Technology W.J.T. |
| RESOURCES: |
Large troubleshooting
chart
Ref — trainer
Overhead
System room |
| EVALUATION: |
Entrance Exam
Give superheat reading for given problem
Give subcool reading for given problem
Get temperature difference across the air evaporator
Get temperature difference across air cooler condenser |
| |
|
| DAY 2 SUBJECT: |
The Troubleshooting Chart And
System Operating Components — Pressure Relief Devices
|
| GOAL: |
Demonstrate how
system performance is affected by poor air flow and to use
dye. |
| OBJECTIVES: |
To use troubleshooting
chart to diagnose different mechanical problems
Understand that troubleshooting chart is a tool for learning
to diagnose A/C system problems
To take correct temperature & pressure measurements
To identify different pressure relief devices and how they
work
How pressure relief’s are piped in a refrigeration system
and why they are needed |
| SUBJECT CONTENTS:
|
HVAC/R industry
terms
Relief devices external
Fusible plug
Spring loaded
Safety reason for relief valves
Solving A/C problems using chart |
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Troubleshooting charts
Overheads
System room |
| RESOURCES: |
Refrigeration &
A/C technology W.J.T.
Troubleshooting handouts
Sporlan TXV
Alco TXV
Henry valve |
| EVALUATION:
|
Homework
Quiz
Solving A/C problem using large troubleshooting chart in front
of class
Shop —
- able to get superheat
- able to get evap air diff. temp
- able to get cond. air . diff. temp.
|
| |
|
| DAY 3 SUBJECT: |
Refrigeration Operating Temperatures
And Defrost Systems |
| GOAL: |
To identify different
refrigeration equipment and temperature ranges. Demonstrate
setting up of low pressure temperature control and the operation
of different defrost controls |
| OBJECTIVES: |
Student will be
able to:
Define refrigeration temperature ranges
- AC high temperature
- Medium temperature
- Low temperature
Identify equipment
- Low boy box
- Reach in box
- Walk in box
- Ice machine
- Heat pump
Discuss/note typical temperatures of evaporators coil temperature
to discharge air temperature
- Control of temperature
- Adjusting of low pressure control
- Fin spacing of different coils
Discuss/note different types of defrost: off cycle, radin,
plane
- Elect
- Hot G
- Start of defrost clock
- Control of evaporator fan
- Termination defrost
- Clock
- Temperature
- Pressure
Understand the function of defrost
- Ice melting
- Returning oil to the compressor
- Use on a heat pump
|
| SUBJECT CONTENTS:
|
Trade language
Temperature ranges
Setting of low pressure switcher
Setting of defrost controls |
METHODS/
TECHNIQUES: |
Classroom handout
Refrigeration & A/C Technology W.J.T.
System room — set up of low pressure control |
| RESOURCES: |
Work book/handouts
Refrigeration & A/C Technology W.J.T.
PT. Char — Dupont, sporlan or alco |
| EVALUATION: |
Homework
Quiz
Shop performance — set up of pressure control |
| |
|
| DAY 4 SUBJECT: |
EPR Control Devices, Refrigerant
Migration Protection.
Troubleshooting Chart |
| GOAL: |
To understand the
EPR valve and how it works with the TXV. To identify the 3
types of refrigerant migration protection strategy and draw
an electrical wiring diagram for each. |
| OBJECTIVES: |
Student will be
able to:
Distinguish between mechanical controls
Explain how an EPR valve functions
Describe electrical controls that apply to refrigerant migration
protection
Discuss how poor air or water flow affected a system differently
than a dirty condenser
Draw wiring diagram of 3 types of refrigeration migration
protection |
| SUBJECT CONTENTS:
|
Trade terms
EPR control diagrams & installation instruction
Review of TXV operation |
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Work book handouts
Overheads
Large troubleshooting chart |
| RESOURCES: |
Refrigeration &
A/C Technology W.J.T.
Sporlan
Alco
Henry
Asco
Dupont — product information |
| EVALUATION:
|
Shop —
show system with pump down
Demonstrate location of EPR valve installation
Demonstrate location of LL Solenoid installation & make
wiring diagram
Quiz |
| |
|
| DAY 5 SUBJECT: |
Recovery, Evacuation and Leak
Checking |
| GOAL: |
Demonstrate the
use of recovery equipment, vacuum pump & leak checking.
|
| OBJECTIVES: |
Student will be
able to:
Understand the proper procedure to evacuate a refrigeration
system
- Use of the micron gauge (scale)
- Best line size
- Heat lamps
Connect a recovery machine
- Push pull
- Vapor recover
Demonstrate how to leak check:
- Standing pressure test
- Electronic
- Halide leak
- Dye — visible & U.V.
- Sound ultra sonic
|
| SUBJECT CONTENTS:
|
Trade (terms) language
Safety — precaution when using gauge manifold
Robinair vacuum instructions
Robinair recovery instructions
Hazards of working with halide torch leak detector |
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Work book handouts
Overheads |
| RESOURCES: |
Refrigeration &
A/C Technology W.J.T.
Manufacture Instruction & Direction
- Vacuum pump
- Recovery
|
| EVALUATION: |
Homework
Quiz
Shop (PBF) |
| |
|
| DAY 6 SUBJECT: |
Refrigerant Oils And Safety Controls
|
| GOAL: |
Demonstrate how
an oil pressure works and how it is connected to a compressor.
Also how to take net oil pressure on compressors. |
| OBJECTIVES: |
Student will be
able to:
- Understand the purpose for refrigerant oil & types
- Understand net oil pressure reading
- Demonstrate how an oil pressure safety switch is wired
in a circuit
- Explain the function of an oil pressure switch
|
| SUBJECT CONTENTS:
|
Trade (terms) language
Safety use of tools & equipment
Installation and testing of an oil pressure safety
Operation of an oil pressure safety switch |
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Work book handouts
Overheads |
| RESOURCES: |
Refrigeration &
A/C Technology W.J.T.
Penn - Johnson |
| EVALUATION: |
PBF
Quiz - written
Homework |
| |
|
| DAYS 7 & 8 SUBJECT:
|
Auxiliary Components — Their
Applications and Operation in the Refrigeration Circuit |
| GOAL: |
To identify by shape
& location on refrigeration piping the different components
& their functions. |
| OBJECTIVES: |
Student will be
able to point out location for component installation &
lines connected to component and it’s purpose.
- Liquid line drier & size it
- Capillary strainer - drier
- Suction accumulator and with heat exchanger
- Mufflers — suction & discharge
- Receivers
- Desuperheatiing heat exchanger
- Subcooling heat exchanger
- Oil separator
- Oil reservoirs
- Sight glasses
- Vibration
- EPR — valve
- CPR — valve
- Relief valve, plug & disk
- Head pressure control
- Fun Cycle
- Fan speed
- Air volume
- Flooding condenser controls, oroa valve
- Solenoid valve
- Pressure switcher
- Low pressure safety
- Low pressure control
- High pressure switch
- Low ambient control
- Oil safety switch
|
| SUBJECT CONTENTS:
|
Trade names of components
Trade terms used (language)
Troubleshooting chart; when components are used
Danger when using torch or system with compressed refrigerants
|
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Work book handouts
Overheads |
| RESOURCES: |
Refrigeration &
A/C Technology W.J.T.
Refrigeration Research Inc.
Alco
Sporlan
Ranco
Penn — Johnson
Large Troubleshooting Chart |
| EVALUATION: |
Homework
Quiz |
| |
|
| DAY 9 SUBJECT: |
Cooling Towers; Water Supplies
& Water Reg Valve |
| GOAL: |
Demonstrate simple
maintenance service on tower, back flush a condenser and adjust
a water valve |
| OBJECTIVES: |
Student will be
able to:
Discuss/understand the operation of a cooling tower
Identify different types of towers
- Forced Air
- Natural Draft
Discuss the water supply & treatment for cooling tower
Identify safety conditions when working on indoor & outdoor
towers
Discuss adjusting/flushing water valve |
| SUBJECT CONTENTS:
|
Trade language (terms)
Poor safety attitude
The effect of electrical shock
Danger of flooding space
Freeze up |
METHODS/
TECHNIQUES: |
Work book handouts
Overheads
PBF in system room |
| RESOURCES: |
Marley tower
Metrey
Penn - Johnson |
| EVALUATION: |
Homework
Quiz
PBF |
| |
|
| DAY 10 SUBJECT: |
Evaporative Condensers, Evaporative
Fluid Cooler and Drycoolers |
| GOAL: |
To understand different
type of head rejection devices operation temperature and use
in winter operation |
| OBJECTIVES: |
Student will be
able to:
Identify & define an evaporative condenser, an evaporative
fluid and a drycooler
Discuss temperature drop across each
Discuss winter operation, types of sump heaters, fan cycle
controls |
| SUBJECT CONTENTS:
|
Trade (terms) language
Taking temperature
Check performances
Venting lines
Safety with electrical around water |
METHODS/
TECHNIQUES: |
Work book handouts
Overheads
Large troubleshooting charts |
| RESOURCES: |
Marley
EDPAC
BAC
Mammoth Inc.
North American Heat Transfer
Heat Craft |
| EVALUATION: |
Homework
Quiz |
| |
|
| DAYS 11 & 12 SUBJECT:
|
Using Troubleshooting Chart to
Find Component Problems |
| GOAL: |
To be able to diagnose
problems where chart leaves off by reason & logic |
| OBJECTIVES: |
Student will be
able to:
- Solve refrigerant service calls
- Check components mechanical & electrical
- Diagnose multiple problems
|
| SUBJECT CONTENTS:
|
Dealing with customers
poor attitudes
Service Industry term & language
Care in taking pressure & temperature reading
Safety on ladders & electric shock
Rules for diagnosing
Problem — to solve |
METHODS/
TECHNIQUES: |
Refrigeration &
A/C Technology W.J.T.
Large troubleshooting chart
Work book
Service calls
System room — role playing |
| RESOURCES: |
Refrigeration &
A/C Technology W.J.T. |
| EVALUATION: |
Quiz
Homework
PBF
Solving Service Problems |
