| I.
Safety
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| 1.
Wear personal protective equipment during operation of
refrigeration equipment.
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| 2.
Describe safety considerations when using electrical testing
equipment.
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| 3.
Wear personal protective equipment when testing high voltage
electrical equipment.
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| 4.
Describe how thermostatic expansion affects trapped liquid
refrigerant.
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|
|
| II.
Metering Devices
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| 1.
Define metering device as used in an ammonia refrigeration system.
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| 2.
Describe the difference between a metering device and an expansion
device in an ammonia refrigeration system.
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| 3.
List and describe three different types of expansion devices.
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| 4.
Describe the internal workings of a thermostatic expansion valve.
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|
|
| III.
Low Side Vessels
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| 1.
List and describe five functions of a low side vessel.
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| 2.
Describe the two most common forms of phase separation in a low
side vessel.
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| 3.
Describe the purpose of the following vessels: surge drum, pumped
liquid recirculating vessel, and inter-cooler.
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| 4.
List and describe four devices used for controlling liquid level
in a low side vessel.
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|
| IV.
Direct Expansion Systems
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| 1.
Describe a direct expansion evaporator system.
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| 2.
Describe the function of the main components in a direct expansion
system.
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| 3.
Explain the differences in velocity between liquid and vapor in a
DX coil.
|
| 4.
Identify the advantages and disadvantages of bottom and top fed
coils.
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| 5.
Describe the importance of a suction line accumulator.
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|
|
| V.
Flooded Systems
|
| 1.
Describe a flooded evaporator system.
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| 2.
List and explain the advantages of a flooded coil over a DX coil.
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| 3.
Describe three methods of liquid level control in a flooded coil
system.
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| 4.
Describe the purpose of a surge drum in a flooded coil system.
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| 5.
List three problems oil creates in an evaporator.
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|
|
| VI.
Pumped Recirculating Systems
|
| 1.
List and describe the two methods used in industrial refrigeration
system for pumping liquid refrigerant.
|
| 2.
List and describe the advantages of gas pumping in a system.
|
| 3.
List and describe the advantages of mechanical pumping in a
system.
|
| 4.
Calculate liquid overfeed rate for ammonia and halocarbon
refrigerants.
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| 5.
List three major problems that migrating oil can cause in a
refrigeration system.
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|
|
| VII.
Secondary Coolant Systems
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| 1.
Describe the eutectic point of brines and glycols.
|
| 2.
List three advantages of a secondary coolant loop.
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| 3.
List five disadvantages of a secondary coolant loop.
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| 4.
Describe a two-pipe secondary coolant system.
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| 5.
Describe a three-pipe secondary coolant system.
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| 6.
List the items to monitor within a brine system.
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|
| VIII.
Heat Flow Characteristics
|
| 1.
Explain the four factors that control the conduction of heat from
one material to another.
|
| 2.
Identify factors that either increase or decrease cooling effect.
|
| 3.
Describe how thermal conductivity, or K Factor, affects heat
transfer.
|
| 4.
Plot a simple DX refrigeration cycle on a pressure-enthalpy
diagram.
|
| 5.
Identify the lines representing the four basic components on the
pressure-enthalpy diagram.
|
| 6.
Calculate the theoretical discharge temperature, Latent heat of
vaporization, refrigerating effect, and the percent of flash gas
from the pressure-enthalpy diagram.
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| 7.
Identify and explain the lines on a pressure-enthalpy diagram:
constant quality, constant pressure, isothermal, constant
enthalpy, constant entropy, and specific volume.
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|
|
| IX.
Two Stage Systems
|
| 1.
Describe the advantages of a two-stage system operating at higher
compression ratios.
|
| 2.
Describe the function of an inter-cooler.
|
| 3.
Explain why the operating cost of a two-stage system is lower than
a single stage system.
|
| 4.
Plot a two-stage system on a pressure enthalpy diagram and explain
the advantages from single stage.
|
| 5.
Describe the layout of a simple two-stage system.
|
| 6.
Describe a Cascade System.
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| 7.
List the advantages of a cascade system.
|
| 8.List
the disadvantages of a cascade system.
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|
|
| X.
Competency Skills
|
| 1.
Follow oral instructions: Listen for and identify key words
. Listen for words
that identify a procedure.
Listen for steps or
actions to be performed.
Listen for clues
regarding the order or sequence in which a task is performed.
|
| 2.
Participate in group communication activities.
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| 3.
Estimate, apply and solve problems involving fractions,
decimals, percentages, and real numbers.
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| 4.
Convert common units of measurement within and/or across
measurement systems (metric/English, etc.).
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| 5.
Construct and interpret tables, charts, maps, and/or graphs.
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| 6.
Compile and maintain records, logs, lab notebooks, and other
documents.
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| 7.
Build group consensus: Clarify statements.
Reconcile disputes
and disagreements,
Propose alternative plans for action. Respond positively to
ideas and suggestions.
Express agreement or neutrality.
Demonstrate conflict
resolution skills.
Express disagreement diplomatically.
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| 8.
Set priorities or the order in which several tasks will be
accomplished.
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