Unit 8 Test and Quiz Review

C

A 1/4 inch service hose will only allow a vacuum pump to pull at ___________ CFC, regardless of the pump's CFM rating. A. 3.0 B. 1.0 C. 0.8 D. 0.25

B

A __________________ can remove any type of foreign matter that enters a refrigeration system A. vacuum pump B. filter drier C. recovery machine D. compressor

D

A deep vacuum can most accurately be measured in A. inches of mercury B. inches of water column C. pounds per square inch D. microns

A

A large refrigeration system that contains a significant amount of moisture should be evacuated with A. a high CFM vacuum pump B. a low CFM vacuum pump C. the system compressor running D. a recovery machine then a nitrogen sweep

C

A system that is equipped with a ___________________ may require additional steps to ensure that the entire system is evacuated A. TXV B. Relief valve C. solenoid valve D. receiver

True

A system with Schrader valve gauge ports will take longer to evacuate than a system with service valves True or False

B

A(n) _____________ leak detector requires a lubricant-specific dye be injected into a charged system to find the leak. A. Halide B. Ultraviolet C. Electronic D. Ultrasonic

A

An evacuation process that is performed a number of times with nitrogen being used to break the vacuum, and ends with a deep vacuum is known as A. triple evacuation B. refrigerant recovery C. system flush D. nitrogen sweep

D

An oily dust spot on a condenser or evaporator coil could indicate A. a defective fan motor B. noncondensables in the system C. the presence of acid D. a refrigerant leak

B

Atmospheric pressure, 0 psig is the equivalent of about ____________ microns. A. 0 B. 760,000 C. 635,000 D. 100,000

D

In order to remove moisture from a refrigeration system using a vacuum pump, it must be in a ________________ state A. solid B. heated C. liquid D. vapor

D

Leaks that occur only when the unit is in operation are called A. combination-dependent leaks B. temperature-dependent leaks C. cumulative microleaks D. vibration-dependent leaks

B

Leaks that require two or more conditions in order to induce leakage are known as A. cumulative microleaks B. combination-dependent leaks C. temperature-dependent leaks D. standing pressure leaks

D

Moisture, acid buildup, and copper plating can be caused by which of the following? A. Refrigerant and oil mixing B. A clogged filter dryer C. An undersized evaporator D. Air in the system

A

One of the advantages of a microfoam leak detection solution over standard bubble solutions is that it A. will not pit or corrode the components B. contains chlorides C. can detect leaks as small as 0.1 oz per year D. will react with refrigerant oil and become luminescent

C

Proper evacuation without the use of a gauge manifold requires which of the following? A. Recovery machine B. Nitrogen and a pressure regulator C. Core removal tool D. Electronic leak detector

B

Proper maintenance for a vacuum pump would include which of the following? A. Replacing all of the caps and plugs with new ones B. Changing the oil as often as necessary C. Replacing the oil sight glass D. Installing a new motor on the pump

D

Removing air and/or other noncondensable gases from a system using a vacuum pump is called __________. A. Dehydration B. Evacuation C. Recovery D. Degassing

B

Sludge and other solids can be removed from a system by using _______________. A. nitrogen and a trace gas B. liquid-and suction-line filter/driers C. a recovery machine D. vacuum pump and a micron gauge

B

Standing, pressure-dependent, temperature-dependent, vibration-dependent, combination-dependent, and micro are all types of A. charging methods B. leak methods C. evacuation methods D. electronic micron gauges

D

The _______________ is both the greatest asset and the greatest liability of an electronic leak detector A. range B. battery life C. cost D. sensitivity

C

The low-pressure side of the system must not be pressurized to more than ___________ when testing for leaks. A. 75 psig B. 200 psig C. the low-side design pressure D. atmospheric pressure

B

The mechanical strain of motion, rotation, and refrigerant flow are all associated with __________ leaks. A. pressure-dependent B. vibration-dependent C. temperature-dependent D. combination-dependent

D

The most accurate type of gauge for measuring a deep vacuum is a A. compound gauge B. digital manometer C. mercury manometer D. digital micron gauge

C

The most common type of system leaks are ___________ leaks. A. vibration-dependent B. pressure-dependent C. standing D. temperature-dependent

C

The only two substances that should be circulating in a refrigeration system are A. liquid and vapor B. refrigerant and nitrogen C. refrigerant and oil D. nitrogen and oil

False

The process of a solid changing to a vapor without passing through the liquid state is called dehydration. True or False

A

The process of removing both noncondensable gases and water vapor is called __________. A. Evacuation B. Dehydration C. Recovery D. Degassing

C

Two types of evacuation methods used by technicians are A. active recovery and passive recovery B. system-dependent and self-contained C. deep vacuum and triple evacuation D. nitrogen sweep and standing pressure test

B

When a deep vacuum is reached (500 microns), the system is valved off and observed for 10 to 15 minutes. A rise in pressure could indicate which of the following? A. It is normal and does not indicate anything B. There may be a leak or the presence of air and/or moisture C. The system charge was not properly recovered prior to evacuation D. There may be acid or sludge in the system

B

When checking for a leak in the evaporator coil, the leak detector can be placed A. in the airstream B. in the drain outlet C. in the return D. next to the evaporator fan

B

When leak checking the suction line with an electronic leak detector, the probe should be placed A. near the receiver B. under the pipe insulation C. in the condenser air stream D. in the evaporator ai stream

D

Which of the following conditions requires a system cleanup, an oil test, and oversized filters to be added to the system? A. Noncondensables in the system B. A vibration-dependent leak in the evaporator C. A temperature-dependent leak in the compressor discharge line D. A compressor motor burnout

A

Which of the tools used during the evacuation process can be wireless and use Bluetooth technology? A. Micron gauge B. Vacuum pump C. Core removal tool D. Evacuation hoses