You are changing out the compressor of a system containing 40 pounds

When first inspecting a hermetic system known to be leaking, you should look for;
A. frost on the tubing.
B. puddles of refrigerant.
C. particles of filter drier core.
D. traces of oil.

When a trace gas becomes absolutely necessary, which of the available gases should be used to help
locate a leak?
A. Nitrogen with HCFCR-22.
B. R-22 due to its universal system compatibility and its miscibility with various oils.
C. Nitrogen with a trace amount of the system's design refrigerant.
D. Nitrogen with HFC R-410A.

C. Nitrogen with a trace amount of the system's design refrigerant

A chiller for comfort cooling that contains 50 pounds or more of R-123 is leaking. Starting in 2019, at
what leak rate does the EPA require that the equipment be repaired?
A. 5%
B. 10%
C. 15%
D. 20%

A comfort-cooling appliance containing 50 pounds or more of R-22 is found to be leaking beyond the
applicable leak rate threshold. Unless granted additional time, how many days do you have to repair the
leak and conduct the initial leak verification test?
A. 1 days
B. 10 days
C. 30 days
D. 45 days

How long must owners and operators of regulated appliances normally containing 50 or more pounds of
HCFC refrigerant keep records of leak inspections, initial leak verification and follow-up verification tests?
A. 2 years
B. 3 years
C. 5 years
D. Life of the appliance

After refrigerant liquid has been recovered from the appliance, any remaining vapor is;
A. purged to the atmosphere.
B. isolated in the appliance.
C. pumped into appliance receiver.
D. removed by the recovery system.

D. removed by the recovery system

Why could a recycling or recovery machine that uses a hermetic compressor overheat when drawing
deep vacuums?
A. It runs faster than other equipment with oil less compressors.
B. The motor relies on the flow of refrigerant through the compressor for cooling.
C. It has a higher compression ratio limit than other equipment.
D. The oils used in hermetic compressors are a lower viscosity than the oils used in other equipment

B. The motor relies on the flow of refrigerant through the compressor for cooling.

What should be done before transferring refrigerant to an empty cylinder?
A. The refrigerant should be chilled.
B. The refrigerant should be mixed.
C. The cylinder should be heated.
D. The cylinder should be evacuated

D. The cylinder should be evacuated.

What steps should be taken before using a recovery unit to remove a charge?
A. The refrigerant should be tested for acid.
B. The recovery unit should be purged with nitrogen.
C. The recovery unit oil should be changed and recovery cylinder evacuated.
D. Service valve positions and recovery oil level should be checked, when applicable

C. The recovery unit oil should be changed and recovery cylinder evacuated.

When should refrigerant be removed from the condenser outlet?
A. When the condenser is below the receiver.
B. When the condenser is on the roof.
C. When the condenser is inoperative.
D. When the evaporator has a small leak.

A. When the condenser is below the receiver.

An operating unit that has a receiver/storage tank requires refrigerant system service. When servicing
the unit;
A. the compressor should be valved off.
B. liquid refrigerant should be recovered last.
C. refrigerant should be pumped down to and isolated in the receiver.
D. a gauge pressure of "Ol/psi should be achieved by venting.

C. refrigerant should be pumped down to and isolated in the receiver

How long must an HVAC servicing company keep records for each disposed appliance with a charge
between 5 and 50 pounds?
A. 1 year
B. 3 years
C. 5 years
D. 10 years

Which ofthe following statements about recycling and recovery equipment is FALSE?
A. It must be tested by an EPA-approved third party
B. Purchases of such equipment must be reported to the EPA
c. It must be equipped with low-loss fittings
D. Equipment designed to recover flammable refrigerant must meet a specific UL safety standard

B. Purchases of such equipment must be reported to the EPA

You are changing out the compressor of a system containing 40 pounds of R-404A. In addition to
isolating the compressor, which of the following procedures should you follow?
A. Simply remove the compressor and cap the ends.
B. Evacuate the isolated section of the system to atmospheric pressure, then remove the compressor.
C. Evacuate the isolated section of the system to 0 psig and if system pressure does not rise after a few
minutes, remove the compressor.
D. Evacuate the isolated section of the system to 5 inches of vacuum and when the system's pressure
rises out of the vacuum, remove the compressor.

C. Evacuate the isolated section of the system to 0 psig and if system pressure does ntit rise after a few
minutes, remove the compressor.

What should be done after reaching the required recovery vacuum on an appliance?
A. Immediately disconnect the recycling or recovery equipment, and open the system for service.
B. Wait for at least a few minutes to see if the system pressure rises.
C. Break the vacuum with nitrogen and open the system for service.
D. Pressurize the system with nitrogen and perform a leak check.

. Wait for at least a few minutes to see if the system pressure rises.

Before making a major repair, technicians must evacuate an appliance or component containing more
than 200 pounds of R-41OA to which of the following levels?
A. 0 psig
B. 25 mm Hg absolute
C. 10 inches of Hg vacuum
D. 15 inches of Hg vacuum

C. 10 inches of Hg vacuum

When can appliances containing refrigerants be recovered to atmospheric pressure?
A. For major repairs such as replacing the compressor, condenser, or evaporator.
B. The repair is followed by an evacuation of the appliance to the environment.
C. Leaks in the appliance make recovery to the prescribed level unattainable.
D. The appliance is being disposed of and recycled.

C. Leaks in the appliance make recovery to the prescribed level unattainable

Which of the following repairs would always be considered "major" under EPA's regulations?
A. Replacement of an evaporator coil.
B. Replacement of a filter-drier.
C. Replacement of a Schrader valve core.
D. Replacement of a condenser fan motor

A. Replacement of an evaporator coil.

When is it against EPA regulations to use system-dependent recovery equipment?
A. When the compressor of the appliance is operational.
B. When the ambient temperature is over 105'F.
C. When the appliance contains over 15 pounds of refrigerant.
D. When the appliance is leaking

C. When the appliance contains over 15 pounds of refrigerant

What is the evaporation temperature of R-134a at 0 psig?
A. -21°F
B. -15°F
C. -5°F
D. -1°F

A. -21°F
B. -15°F
C. -5°F
D. -1°F

Which of the following is a reason to take an oil sample?
A. A new filter drier has been installed.
B. The unit has had a compressor burnout.
C. The unit is not cooling properly.
D. Recycled refrigerant has been added to the unit.

B. The unit has had a compressor burnout.

What are refrigeration and air-conditioning compressor heaters used for?
A. To reduce the amount of refrigerant in the oil.
B. To prevent refrigerant vaporization.
C. To reduce the amount of entrained water in the receiver.
D. To prevent acid pitting.

A. To reduce the amount of refrigerant in the oil.

It is best practice to use dry nitrogen to break the vacuum when dehydrating by the triple evacuation
method. However, it;
A. often contains moisture.
B. requires a minimum of 10 psig.
C. is toxic when released into the atmosphere.
D. requires a pressure regulator

D. requires a pressure regulator

Every refrigerating system must be protected by which of the following?
A. A pressure relief device.
B. A properly located stop valve.
C. A low pressure control.
D. A refrigerant receiver

A. A pressure relief device.

Pressure relief valves can only be installed;
A. in series.
B. in parallel.
C. vertically.
D. horizontally

You are changing out the compressor of a system containing 40 pounds