Free Practice Quiz Question List

4 Type III: Low-Pressure Appliances Online Quiz Questions

Use this free practice quiz with 20 questions to review 4 Type III: Low-Pressure Appliances, test your knowledge, and prepare for your next test or exam.

20 questions

Fill in the blank

1 point

When recharging a centrifugal chiller, introduce vapor before liquid through the .

Choose one

1 point

When practical, which sequence should a technician use to recover refrigerant from a chiller?

A
Recover vapor first, then liquid.
B
Recover liquid first when practical, then recover the remaining vapor.
C
Mix refrigerants to simplify recovery.
D
Open the appliance before reaching its recovery endpoint.

Written response

1 point

What equipment can help identify a leaking chiller tube?

Choose one

1 point

A low-pressure chiller requires leak testing. Which approach uses a preferred pressurization method?

A
Pressurize with oxygen or compressed air.
B
Use nitrogen as the preferred method in every case.
C
Use controlled hot water or a built-in heating/pressurization device.
D
Run the purge unit continuously instead of pressurizing the system.

Written response

1 point

For Type III exam review, what is the maximum nitrogen pressure for leak-testing a low-pressure centrifugal chiller? Enter the value in psig.

Choose all

1 point

Select all correct steps or conditions for removing oil from a low-pressure appliance.

A
Heat the oil to about 130°F before removal.
B
Bring the appliance or isolated section to no more than 5 psig before removing oil.
C
Raise the appliance pressure above 5 psig to release dissolved refrigerant.
D
If draining into a receiver, bring the receiver to no more than 5 psig.

Fill in the blank

1 point

During chiller evacuation, circulate or remove water from the tubes as appropriate to .

Written response

1 point

What is the standard Section 608 evacuation target for a low-pressure appliance? Enter the pressure value in mm Hg absolute.

Choose all

1 point

A leak prevents a low-pressure appliance from reaching its normal evacuation level. Select all correct actions described for this situation.

A
Evacuate non-leaking components to the required level where possible.
B
Leave non-leaking components unevacuated if any section is leaking.
C
Evacuate leaking sections to the lowest attainable level, not above 0 psig.
D
For leaking sections, always exceed 0 psig to reach the normal target.

Choose one

1 point

Before applying a leak-rate threshold or reporting requirement to a chiller, what should a technician do?

A
Apply the same leak-rate threshold to every chiller.
B
Identify the relevant appliance, refrigerant, charge, and regulatory program before applying a threshold.
C
Use purge frequency alone to determine the applicable leak-repair threshold.
D
Apply a threshold based only on the chiller's size.

Written response

1 point

A low-pressure chiller needs frequent purging. What should this clue prompt a technician to investigate?

Open ended

1 point

Explain how the standard low-pressure appliance evacuation target differs from the special procedure that may apply to certain non-major repairs not followed by evacuation to the atmosphere.

Choose one

1 point

In a water chiller cycle, which process occurs in the condenser?

A
It absorbs heat from building water and boils refrigerant into vapor.
B
It rejects heat from refrigerant and condenses it into liquid.
C
It compresses refrigerant vapor to raise its pressure and temperature.
D
It lowers liquid refrigerant pressure before it returns to the evaporator.

Choose one

1 point

A leak develops in an evaporator operating below atmospheric pressure. What can happen?

A
Refrigerant always flows outward, while air and moisture are blocked.
B
Air enters only if the purge unit is switched off.
C
Air and moisture can be drawn into the system through the leak.
D
The leak immediately raises the system above atmospheric pressure.

True or false

1 point

If a low-pressure chiller’s purge unit operates frequently, this alone identifies the location of the leak.

A
True
B
False

Choose one

1 point

You need to raise pressure to leak-test a low-pressure centrifugal chiller. Which approach follows the recommended method and nitrogen limit?

A
Use controlled hot water or a built-in heating/pressurization device when appropriate; if nitrogen is used, stay at or below 10 psig.
B
Use compressed air and increase pressure until the leak becomes audible.
C
Use oxygen at 10 psig because it is the preferred test gas.
D
Use nitrogen at 10 psig as a required target, regardless of the appliance’s rated limits.

Choose one

1 point

When recovering refrigerant from a chiller, which sequence is recommended when practical?

A
Recover vapor first, then leave any liquid refrigerant in the appliance.
B
Recover liquid first when practical, then recover the remaining vapor.
C
Mix refrigerants to make recovery faster.
D
Release liquid refrigerant before connecting recovery equipment.

Choose one

1 point

During chiller evacuation, refrigerant pressure and temperature are falling. What should you do about water in the tubes?

A
Close the water circuit and leave the tubes full throughout evacuation.
B
Add compressed air to the water circuit to maintain tube temperature.
C
Circulate or remove water from the tubes as appropriate to prevent freezing.
D
Drain the refrigerant before evacuation so the water remains warm.

True or false

1 point

A technician is filling a refrigerant recovery cylinder. The cylinder is intended for refrigerant and has reached 80% of its capacity. Is it acceptable to stop filling at this point?

A
True
B
False

True or false

1 point

An equipment room may be oxygen-deficient. A technician who lacks the required training and equipment should not enter the room.

A
True
B
False

4 Type III: Low-Pressure Appliances Online Quiz Questions

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