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The Laboratory Manual for Fundamentals of HVACR Laboratory Manual, Second Edition,
allows for different lab settings and associated equipment. Therefore answers to procedural
LAB 2.1 HVACR JOBS
Entry-level helper, Rough-in installer, Start-up technician, Service technician, Sales,
Equipment operator, Facilities maintenance personnel, Service manager, Systems
LAB 2.2 HVACR ORGANIZATIONS
The Air Conditioning, Heating, and Refrigeration Institute (AHRI) is a national
trade association representing manufacturers of over 90% of United States-
produced central air conditioning, gas appliances, and commercial refrigeration
equipment. AHRI was formed in 2007/2008 when ARI (Air Conditioning and
Refrigeration Institute) merged with GAMA (Gas Appliance Manufacturer’s
Association). ARI, now AHRI, was originally formed in 1954 through a merger of
The Refrigeration Service Engineers Society (RSES) is the international professional
association for all HVAC/R workers and is dedicated to education and certification of
technicians in the HVAC/R industry. RSES offers Specialist Certification for senior
technicians in eight HVAC/R areas and has a technician EPA certification program.
RSES chapters conduct classroom training in technical areas and are a source for
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educational printed material and books.
North American Technical Excellence (NATE) is an independent, third party
certification body formed in the 1997 as a result of a concern expressed by many in the
industry that there was not a way of distinguishing quality, highly skilled HVACR
HVAC Excellence is a not for profit organization that has been serving the HVACR
industry since 1994. The organization’s goal is to improve competency through
validation of the technical education process by offering progressive levels of
technician certification through its HVAC Excellence programs.
Skills USA is a vocational industrial club for students in high schools, trade
schools, and community colleges. Skills USA clubs are open to students in all
areas of specialties including HVACR. The national organization provides local
LAB 3.1 SAFETY DATA SHEETS (SDS)
The first place to begin with any new refrigerant is to review the SDS (Safety Data
Sheet). An SDS will accompany a newly purchased refrigeration cylinder if
requested. Another way to access an SDS is to download it from the Internet, as these
are often made available by refrigerant manufacturers. It is advisable to have a
For many years, the material safety data sheet (MSDS) has been the back-bone of
OSHA’s Hazard Communication Standard. This Standard was recently revised (29 CFR
1910.1200(g)) and has resulted in many changes including the replacement of MSDSs by
safety data sheets (SDSs). Some overlap is expected during the transition from MSDSs
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hazardous chemical shipments, warning users of the specific dangers of such products
and guidance of their safe handling, storage and disposal. These sheets must be made
accessible by the employer because employees have the right to know about the
chemicals to which they are exposed. Additionally, employers are required to:
1. Maintain a hazard communication program detailing the plans in place for the safe
handling of chemicals.
2. Maintain a written chemical inventory of every hazard chemical in the facility to
which employees are exposed.
4. Train employees on chemical hazards and necessary precautions.
Figure 3-10 depicts the pictograms that manufacturers must include on product
container labels effective June 1, 2015. You should read SDSs on any material before
you use it so you know how to use it properly and safely and know what to do if there is
an accident involving the material. The SDS has sixteen sections as follows:
that are acute or delayed.
Section 5 – Fire-fighting measure lists suitable extinguishing techniques, equipment
and any chemical hazards from fire.
Section 6 – Accidental release measures provides recommendations on the appropriate
response to spills, leaks, or releases. This includes containment, cleanup, and protective
and information on any possible hazardous reactions with other materials.
Section 11 – Toxicological information includes the likely routes of exposure such as
inhalation, ingestion, skin and eye contact. Also listed are the related symptoms, acute
and chronic effects; and numerical measures of toxicity.
Section 12 – Ecological information provides information to evaluate the
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Section 14 – Transport information provides guidance on classification information
for shipping and transporting of hazardous chemical(s) by road, air, rail, or sea.
Section 15 – Regulatory information may list any national and/or regional regulatory
information of the chemical mixtures including OSHA, DOT, EPA, and Consumer
manufacturer’s instructions.
LAB 3.2 HVACR PPE
Personal protection equipment (PPE) is designed to reduce your exposure to hazards that
cannot be eliminated or controlled. PPE may include equipment or devices to protect
your head, face, eyes, ears, respiratory system, hands, and feet. Some devices, such as
safety glasses, are commonly used, while others, such as respiratory protection, may be
less frequently used.
If PPE is required for any job, OSHA (Occupational Safety and Health Administration)
recommends that all employees be trained. This training may be as short as a few minutes
Head Protection: An approved hard hat should be worn whenever there is a danger of
things dropping on the head or where the head may be bumped. On a construction site,
proper safety head gear is a must.
Eye and Face Protection: The majority of eye injuries are the result of flying or falling
objects. Most of these objects are smaller than the head of a pin but can cause serious
injury. Approved eye or face protectors must be worn whenever there is a danger of
objects striking the eyes or face. Side shields must be part of any safety glasses worn,
even if they are prescription eyeglasses. Safety glasses or goggles must be worn over
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Ear Protection: Hearing protection devices must be worn whenever there is exposure to
high noise levels of any duration. These devices are of two types: (1) ear plugs, which are
inserted in the ear, and (2) headphones, which cover the ear. Either one must be properly
selected on the basis of how much protection is required.
Respiratory Protection: There are two main types of respirators; (1) air-purifying
respirators are ones that purify the air by filtering out harmful dust, mist, metal, fumes,
gas, and vapor; and (2) atmosphere-supplying respirators are ones that supply clean
breathing air from a compressed air source. The second type should always be worn
when working in a confined space where concentrations of harmful substances are very
high or where the concentration is unknown. Remember that most refrigerants are
odorless, tasteless, and invisible and can cause asphyxiation in a very short time.
Hand, Foot, and Back Protection: There are many different kinds of gloves used for
hand protection, as shown in Some are made for special uses, such as gloves of steel
mesh or Kevlar to protect against cuts and puncture wounds. Different glove materials are
needed to protect against a variety of different chemicals. Choose the right kind from a
dependable supplier who can supply information to lead you to the right gloves. Discard
any damaged ones. Lifting heavy objects improperly can lead to back injury. Always
bend at the knees and lift straight upward rather than bending over, which will place
LAB 3.3 LOCATE SAFETY EQUIPMENT
This is an exercise to familiarize the students with the safety equipment located in your
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LAB 3.4 LADDER SAFETY
Access equipment refers to ladders and scaffolds that are used to reach locations not
accessible by other means. The precautions to be practiced in the use of ladders are:
oOnly use CSA- or ANSI-approved ladders. Maintain ladders in good condition,
and inspect ladders before each use. Discard ladders needing frequent repairs or
people. Follow maximum load rating.
oNever use a broken ladder. Never place a ladder for use on top of scaffolding, and
never use a borrowed ladder on someone’s property. Always use your own ladder
even if you need to leave the job site to go get it.
oAlways face the ladder and use both hands when climbing or descending a ladder.
oUse fiberglass or wood ladders when doing any work around electrical lines
The following recommendations apply to scaffolds:
oScaffolds must be supported by solid footings.
oA scaffold having a height exceeding three times its base dimension must be
secured to the structure. When rolling scaffolds are used, the wheels must be
locked when there are workers on the scaffold.
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Fall Protection:
OTwo types of equipment for preventing injury from falling are (1) fall-prevention
equipment and (2) fall-arresting equipment. either of these methods is required
when working at heights over 10 ft above grade when no other means has been
provided for preventing falls.
oIn fall prevention, a worker is prevented from getting into a situation where a fall
can occur. For example, a safety belt attached to a securely anchored lanyard will
LAB 4.1 USING HAND TOOLS
Unit 4 in the 3rd edition of the Fundamentals of HVACR text describes the proper way to
use tools.
Tool manufacturers package tools in kits that are available for most types of HVAC/R
jobs. They are easier to store and have greater convenience than loose tools. Kits come in
many sizes and price ranges. A complete kit would include wrenches, hex keys,
screwdrivers, nut drivers, pliers, knives and cutters, measurement tools, electrical repair
tools, flaring/swaging/cutting tools, a multi-meter, a gauge manifold set, and a clamp on
ammeter.
The basic tool kit should include varying sizes of combination, adjustable, refrigeration
service, and hex key (Allen) wrenches. There should be an assortment of slotted, and
Phillips screwdrivers along with nut drivers. Pliers are an essential tool for the technician
LAB 5.1 FASTENER IDENTIFICATION
You should select a specific group of fasteners for this lab prior to the beginning of the
exercise rather than let the students choose at will. This is to allow you to correct the
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LAB 7.1 BALLOON – GAS VOLUME VS. TEMPERATURE
LAB 7.2 BALLOON – WEIGHING SOLID, LIQUIDS, AND GASES
Pounds would be a rounded value while pounds and ounces will be more accurate.
LAB 7.3 MEASURING DENSITY, SPECIFIC VOLUME, AND SPECIFIC GRAVITY
Solid
Gas
LAB 8.1 ENERGY CONVERSION
LAB 9.1 MEASURING TEMPERATURE
There are no specific solutions for this lab exercise as the temperatures will vary. In
LAB 9.2 BOILING POINT VS. PRESSURE
Step 2
oThe pressure goes down.
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oThe water stops boiling because the pressure has increased and this will increase
the required boiling temperature.
LAB 9.3 PRESSURE-TEMPERATURE RELATIONSHIP OF SATURATED MIXTURES
Step 3
oThe refrigerant cylinder with the most refrigerant would have an equal pressure to
the cylinder with the least amount of refrigerant. Both cylinders must have the
same refrigerant type, contain both vapor and liquid, and be at the same
temperature. The pressure of a cylinder of saturated refrigerant with 5 lb of
refrigerant will have the same pressure as a cylinder with 20 lb of refrigerant if
Step 6
oThe pressure predicted by the gas law may be different than the actual pressure
because this is a saturated mixture and not 100% gas. Saturated gases do not
Step 7
oThe student should find similar results to Step 6 when comparing the predicted
LAB 9.4 SENSIBLE AND LATENT HEAT
The answers for the calculations found in Step 3 and Step 4 will vary depending
on the measured weight of the water and the wattage reading. The formulas are
provided so the students should be able to use the values they have recorded and
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oIt takes considerably more energy to make steam as compared to heating
water. Only 1 Btu would be required to heat 1lb of water 1 °F, however it
would take 970 Btu to change the same 1lb of water to steam.
LAB 9.5 DETEMINING REFRIGERANT CONDITION
The measured values for this lab will vary depending on the type of trainer used, the
type of refrigerant in the trainer and the operating conditions at the time the
LAB 9.6 MEASURING WATER SOURCE HEAT PUMP SYSTEM CAPACITY
The answers for this lab will vary depending on the water flow and heat pump
efficiency. The formulas are provided so the students should be able to use the values
LAB 9.7 SENSIBLE AND LATENT HEAT
The answers for the calculations will vary depending on the measured weight of the
LAB 9.8 SATURATED PRESSURE-TEMPERATURE RELATIONSHIPS
The refrigerant cylinder with the most refrigerant would have an equal pressure to the
cylinder with the least amount of refrigerant. Both cylinders must have the same
refrigerant type, contain both vapor and liquid, and be at the same temperature. The
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oThe pressure predicted by the gas law may be different than the actual pressure
because this is a saturated mixture and not 100% gas. Saturated gases do not
follow the ideal gas laws.
oThe pressure from the chart should be close to the actual pressure but it may need
to be rounded to the closest value depending on the chart used.
LAB 9.9 SATURATED, SUPERHEATED, OR SUBCOOLED
The measured values for this lab will vary depending on the type of trainer used, the type
of refrigerant in the trainer and the operating conditions at the time the measurements are
taken.
LAB 10.1 QUANTITY-PRESSURE RELATIONSHIP OF IDEAL GASES
The answers for the calculations will vary depending on the measured weight and cylinder
LAB 10.2 GAS TEMPERATURE AND VOLUME AT CONSTANT PRESSURE
When the temperature drops the gas volume decreases and the balloon becomes smaller.
LAB 10.3 GAS PRESSURE-TEMPERATURE RELATIONSHIP AT A CONSTANT
VOLUME
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oThe measured results should be close to the calculated results because nitrogen is
an ideal gas and should follow the ideal gas laws.
Step 5
oWhen the temperature of the cylinder containing nitrogen increases, then the
pressure will also increase.
oThe measured results should be close to the calculated results because nitrogen is
an ideal gas and should follow the ideal gas laws.
oAt a constant volume such as a refrigerant cylinder, the pressure of an ideal gas
such as nitrogen contained in the cylinder will vary with temperature according to
the ideal gas law relationships.
LAB 10.4 GAS PRESSURE-TEMPERATURE-VOLUME RELATIONSHIP
LAB 10.5 AIR COMPRESSION AND EXPANSION
When the air is compressed the temperature increases.
LAB 10.6 IDEAL GAS LAWS
The answers for the calculations will vary depending on the measured weight and cylinder
temperature.
oWhen the temperature of the cylinder containing nitrogen drops, then the pressure
LAB 12.1 IDENTIFYING REFRIGERATION SYSTEM COMPONENTS
You should select a specific group of refrigeration systems for this lab prior to the
beginning of the exercise rather than let the students choose at will. This is to allow you
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LAB 12.2 IDENTIFYING REFRIGERATION SYSTEM COMPONENTS
This is similar to Lab 12.1 but in an easier format for grading and provides the student with
choices.
LAB 12.3 TRAINER REFRIGERATION SYSTEM CHARACTERISITICS
The measured values for this lab will vary depending on the type of trainer used, the type
of refrigerant in the trainer and the operating conditions at the time the measurements are
taken.
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Type of Change Compressor Condenser Metering Device Evaporator
Change in
Heat
Small increase
Large decrease
No change
Large increase
Change in
Volume
Small decrease
Large decrease
Small increase
Large increase
Results may vary slightly as some refrigeration trainers are designed with a
minimal pressure drop through the evaporator or condenser.
The increased volume through the metering device is due to the creation of “flash
compared to the total change over from vapor to liquid in the condenser which would
create a large decrease in refrigerant volume.
LAB 12.4 PACKAGED UNIT REFRIGERATION CHARACTERISITICS
LAB 12.5 SPLIT SYSTEM REFRIGERATION CHARACTERISITICS
The measured values for this lab will vary depending on the type of split
LAB 12.6 BENCH UNIT REFRIGERATION SYSTEMCHARACTERISITICS
The measured values for this lab will vary depending on the type of bench-unit
LAB 12.7 WATER COOLED SYSTEM CHARACTERISITICS
The measured values for this lab will vary depending on the type of water cooled
LAB 12.8 REFRIGERANT IDENTIFICATION
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beginning of the exercise rather than let the students choose at will. This is to allow you
to correct the assignment easier without having to go through what each student may
have randomly selected. You should also make your own answer sheet based upon the
systems that you will be using for the exercise.
If you do not have four different types of systems in the lab then modify the lab to include
the systems that you have available.
Some of the newly developed refrigerants may have zero ozone depletion potential,
however all the refrigerants will have some value for global warming.
The high and low side test pressures set the highest and lowest operable limits for the unit.
The unit should always be operated below these limits.
Pure refrigerants and most azeotropes can be used in either the liquid or vapor form.
LAB 12.9 REFRIGERANT OIL IDENTIFICATION
The results for this lab will vary depending on the three types of refrigeration lubricant
examined. Different types of refrigerant oil are: mineral, polyalkylene Glycol (PAG),
Polyol Ester (POE), Alkyl Benzene (AB), and Polyvinylether (PVE).
You should select a specific group of lubricants for this lab prior to the beginning of the
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LAB 13.1 IDENTIFYING COMPRESSORS
The results for this lab will vary depending on the six types of compressors examined.
You should select a specific group of compressors for this lab prior to the beginning of the
LAB 13.2 SEMI-HERMETIC COMPRESSOR INSPECTION
The results for this lab will vary depending on the make and model of the compressor
LAB 13.3 HERMETIC COMPRESSOR INSPECTION
The results for this lab will vary depending on the make and model of the compressor
examined.
You should select a specific compressor for this lab prior to the beginning of the exercise
rather than let the students choose one at will. This is to allow you to correct the
assignment easier without having to go through what each student may have randomly
selected. You should also make your own answer sheet based upon the compressor that
you will be using for the exercise.
You may choose to use a hermetic compressor that has already been drained and cut in
two.
LAB 13.4 ROTARY COMPRESSOR INSPECTION
The results for this lab will vary depending on the make and model of the compressor
examined and whether it is a stationary blade or rotating blade type compressor.
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You should select a specific compressor for this lab prior to the beginning of the exercise
rather than let the students choose one at will. This is to allow you to correct the
assignment easier without having to go through what each student may have randomly
selected. You should also make your own answer sheet based upon the compressor that
you will be using for the exercise.
High pressure discharge gas enters the shell.
Stationary blade compressor:
oAs the rolling piston rotates, gas will flow in and fill the suction cavity due to the
pressure difference. No suction valve is needed.
LAB 13.5 SCROLL COMPRESSOR INSPECTION
The results for this lab will vary depending on the make and model of the compressor
examined.
You should select a specific compressor for this lab prior to the beginning of the exercise
LAB 13.6 DETERMINING COMPRESSION RATIO
The answers for the calculations will vary depending on the compressor type and
condition. The formula is provided so the students should be able to use the values they
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If the airflow to the evaporator is blocked and the suction pressure decreases, then there
will be a greater difference between the discharge and suction pressures and the
compression ratio will increase.
LAB 13.7 COMPRESSOR AUTOPSY
The results for this lab will vary depending on the make and model of the compressor
examined.
You should select a specific compressor for this lab prior to the beginning of the exercise
LAB 14.1 AIR COOLED CONDENSER PERFORMANCE
The answers for the calculations will vary depending on the measured weight of the water
LAB 14.2 WATER COOLED CONDENSER PERFORMANCE
The answers for the calculations will vary depending on the measured weight of the water
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LAB 15.1 INTERNALLY EQUALIZED THERMOSTATIC EXPANSION VALVES
The diaphragm movement is transmitted to the valve disk through push pins.
LAB 15.2 EXTERNALLY EQUALIZED THERMOSTATIC EXPANSION VALVES
For force diagram see Lab 15.1.
The diaphragm movement is transmitted to the valve disk through a push pin.
LAB 15.3 SETTING A THERMOSTATIC EXPANSION VALVE
LAB 15.4 TYPES OF METERING DEVICES
You should select specific refrigerant systems for this lab prior to the beginning of the
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If you do not have three different types of metering devices in the lab then modify the lab
to include the type of devices that you have available.
LAB 15.5 ADJUSTING AUTOMATIC EXPANSION VALVES
Automatic expansion valves will maintain a set evaporator pressure. Generally turning the
LAB 15.6 DISASSEMBLING TEVs
LAB 15.7 TEV INSTALLATION
LAB 15.8 ADJUSTING VALVE SUPERHEAT
The answers for the measured readings will vary depending on the refrigeration system and
LAB 15.9 CAPILLARY TUBE ASSEMBLY & OPERATION
LAB 16.1 INSTALLING CONDENSATE DRAIN
LAB 17.1 IDENTIFYING REFRIGERANTS AND REFRIGERANT
CHARACTERISITICS
The results for this lab will vary depending on the four types of refrigeration system used.