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310)
310)
Will a chart that only specifies the outdoor ambient temperature still read accurately if the indoor
relative humidity is very far from 50 percent?
A)
No, because the intersection would always fall below the red line in this instance
B)
Yes, because the chart uses both outdoor and indoor dry-bulb temperature
C)
No, because a central assumption of the chart would be inaccurate
D)
Yes, because the chart is based on 400 CFM per ton airflow
Answer:
C
Explanation:
A)
B)
C)
D)
311)
311)
Most vapor charging is done with the compressor operating while charging is taking place;
however, liquid charging:
A)
Is always done with the compressor off.
B)
Is always done with the compressor on.
C)
Is typically done on smaller systems with the system on.
D)
Can be done either with the system off or operating.
Answer:
D
Explanation:
A)
B)
C)
D)
312)
312)
Even with the correct refrigerant charge, a water-cooled system would appear overcharged if:
A)
The air filter was dirty.
B)
It had lower-than-normal water flow through the condenser.
C)
It had higher-than-normal water flow through the condenser.
D)
It had a restricted liquid-line filter drier.
Answer:
B
Explanation:
A)
B)
C)
D)
81
313)
313)
Before changing a fuse, the technician should:
A)
Temporarily jump the fuse out to make sure it needs changing.
B)
Make sure the circuit is energized.
C)
Firmly grab a ground connection.
D)
Make sure the circuit is de-energized.
Answer:
D
Explanation:
A)
B)
C)
D)
314)
314)
What is the smallest gauge wire often used for residential lighting circuits?
A)
12 gauge
B)
14 gauge
C)
18 gauge
D)
16 gauge
Answer:
B
Explanation:
A)
B)
C)
D)
315)
315)
Three different technicians are working on different parts of the same piece of equipment. How
many locks should be on the disconnect?
A)
Three locksone for each technician
B)
No locks are necessary if the equipment is properly labeled "Do Not turn On."
C)
Two locksa primary and a secondary
D)
Only one is necessary because one will keep it from being energized.
Answer:
A
Explanation:
A)
B)
C)
D)
316)
316)
GFCI breakers are typically used for what types of circuits?
A)
On all residential electrical circuits
B)
Circuits in wet locations such as bathrooms
C)
On all electrical circuits
D)
Circuits in dry locations
Answer:
B
Explanation:
A)
B)
C)
D)
82
317)
317)
In order to be injured by an arc flash:
A)
You only need to be near the point of the arc flash.
B)
You must physically contact a live circuit.
C)
You must contact a live circuit and ground.
D)
You must ground yourself.
Answer:
A
Explanation:
A)
B)
C)
D)
318)
318)
Technicians always perform this action first when working on an electrical circuit in a residential
setting:
A)
Test for voltage at the affected unit.
B)
Turn off power at the service panel.
C)
Remove the covers from the affected unit.
D)
Call the power company.
Answer:
B
Explanation:
A)
B)
C)
D)
319)
319)
What procedure is used when heating a brazed copper joint?
A)
Heat the fitting first and then heat the pipe after the fitting is hot.
B)
Use a fanning motion to heat the fitting evenly and slowly.
C)
Concentrate the flame on the line where the pipe slips into the fitting.
D)
Heat the pipe first and then the fitting.
Answer:
D
Explanation:
A)
B)
C)
D)
320)
320)
What controls when Schrader valves open and close?
A)
They open when hoses with depressors are connected to them.
B)
They open when they are backseat cracked and close when they are backseated.
C)
They open and close by a wireless Bluetooth signal.
D)
They open every time the unit starts up and close immediately upon shutdown.
Answer:
A
Explanation:
A)
B)
C)
D)
83
321)
321)
What controls when manual backseating valves open and close?
A)
They open when they are backseat cracked and close when they are backseated.
B)
They open every time the unit starts up and close immediately upon shutdown.
C)
They open and close by a wireless Bluetooth signal.
D)
They open when hoses with depressors are connected and disconnected to them.
Answer:
A
Explanation:
A)
B)
C)
D)
322)
322)
Type I certification applies to which of the following?
A)
MVACs
B)
Small appliances
C)
Large systems
D)
Low-pressure units
Answer:
B
Explanation:
A)
B)
C)
D)
323)
323)
The recovery level for Type III systems using a recovery device manufactured after November 15,
1993, is:
A)
25 in Hg vacuum.
B)
0 psig.
C)
4 in Hg vacuum.
D)
25 mm absolute pressure.
Answer:
D
Explanation:
A)
B)
C)
D)
324)
324)
When using a recovery machine manufactured before November 15, 1993, the recovery level for
Type II systems containing over 200 lb of R-22 refrigerant is:
A)
0 psig.
B)
4 in Hg vacuum.
C)
10 in Hg vacuum.
D)
15 in Hg vacuum.
Answer:
B
Explanation:
A)
B)
C)
D)
84
325)
325)
Select the techniques that can be used to speed up refrigerant recovery. (You may select more than
one.)
A)
Cool the recovery cylinder.
B)
Heat the recovery cylinder.
C)
Use large-diameter hoses.
D)
Use long hoses.
E)
Heat the refrigerant system.
F)
Recover from both sides of the system at once.
Answer:
A, C, E, F
Explanation:
A)
B)
C)
D)
E)
F)
326)
326)
When connecting a recovery system for push-pull liquid recovery, the inlet of the recovery unit is
connected to:
A)
The suction service valve on the system.
B)
The king valve on the system.
C)
The vapor valve on the refrigerant recovery cylinder.
D)
The liquid valve on the refrigerant recovery cylinder.
Answer:
C
Explanation:
A)
B)
C)
D)
327)
327)
Why is a pressure regulator necessary when using nitrogen cylinders?
A)
The nitrogen must be carefully controlled because it is toxic.
B)
To reduce the pressure in the nitrogen cylinder to a safe level
C)
To boost the pressure leaving the nitrogen cylinder high enough to be used
D)
Because the nitrogen is extremely expensive and must be carefully rationed
Answer:
B
Explanation:
A)
B)
C)
D)
85
328)
328)
Leaks in refrigeration systems other than air-conditioning systems, commercial refrigeration
systems, or industrial process cooling systems must be repaired if they have an annual leak rate
of:
A)
10 percent of the charge per year.
B)
15 percent of the charge per year.
C)
25 percent of the charge per year.
D)
35 percent of the charge per year.
Answer:
B
Explanation:
A)
B)
C)
D)
329)
329)
Which of the following measures is the standard airflow across an air-conditioning coil?
A)
400 CFM per ton
B)
600 CFM per ton
C)
500 CFM per ton
D)
300 CFM per ton
Answer:
A
Explanation:
A)
B)
C)
D)
330)
330)
As the outdoor ambient temperature increases, the required superheat:
A)
Increases.
B)
Outdoor ambient temperature does not affect superheat.
C)
Stays the same.
D)
Decreases.
Answer:
D
Explanation:
A)
B)
C)
D)
331)
331)
When metering in zeotropes, why must the liquid flash off to vapor before entering the
compressor?
A)
To prevent too much liquid from damaging the compressor
B)
To ensure maximum efficiency throughout the system
C)
To ensure the unit and cylinder remain in a saturated state
D)
To prevent the system from freezing solid
Answer:
A
Explanation:
A)
B)
C)
D)
86
332)
332)
Systems with fixed-restriction metering devices are critical to charge because:
A)
You must weight both the system and the refrigerant.
B)
The expansion device cannot adjust to changing conditions.
C)
They can only be charged one time.
D)
The large liquid receivers hold so much refrigerant.
Answer:
B
Explanation:
A)
B)
C)
D)
333)
333)
A thermostatic expansion valve system operating with a refrigerant overcharge will have:
A)
A high system subcooling.
B)
Higher temperature drop across the evaporator.
C)
A low superheat.
D)
A low system subcooling.
Answer:
A
Explanation:
A)
B)
C)
D)
334)
334)
What type of injury can a technician receive from an arc flash?
A)
Long-term health effects such as cancer
B)
Severe burns
C)
High blood pressure
D)
Electrical shock
Answer:
B
Explanation:
A)
B)
C)
D)
335)
335)
You need to de-energize a circuit to work on a unit. To ensure your safety, you should:
A)
Work quickly to reduce your exposure to the electricity.
B)
Lock out and tag out the circuit.
C)
Ask a friend to stand beside the disconnect switch to ensure nobody turns it on.
D)
Leave a clearly written"Keep Off" message in 1" block letters.
Answer:
B
Explanation:
A)
B)
C)
D)
87
336)
336)
What is the purpose of locking out an electrical circuit?
A)
To make sure an electrical circuit cannot be turned off
B)
To save on electricity bills
C)
To make sure the customer pays you
D)
To ensure an electrical circuit cannot be energized
Answer:
D
Explanation:
A)
B)
C)
D)
337)
337)
What is the advantage of a noncontact voltage detector over a voltmeter?
A)
It can measure more than one electrical characteristic.
B)
It does not have to contact the energized electrical circuit to indicate voltage.
C)
It provides a more accurate reading.
D)
It connects wirelessly to smartphones.
Answer:
B
Explanation:
A)
B)
C)
D)
338)
338)
When using a recovery device manufactured after November 15, 1993, the recovery level for Type
I appliances is:
A)
80 percent of the system charge.
B)
80 percent of the system charge if the compressor is nonoperational, 90 percent if the
compressor is operational.
C)
80 percent of the system charge if the compressor is operational, 90 percent if the
compressor is nonoperational.
D)
0 psig.
Answer:
B
Explanation:
A)
B)
C)
D)
339)
339)
The recovery level for Type II systems containing less than 200 lb of R-22 refrigerant is:
A)
0 psig.
B)
4 in Hg vacuum.
C)
10 in Hg vacuum.
D)
15 in Hg vacuum.
Answer:
A
Explanation:
A)
B)
C)
D)
88
340)
340)
Refrigerant that has been removed from an appliance and cleaned for reuse without meeting all of
the requirements of ARI-700 is considered:
A)
Recovered refrigerant.
B)
Recycled refrigerant.
C)
Reclaimed refrigerant.
D)
Virgin refrigerant.
Answer:
B
Explanation:
A)
B)
C)
D)
341)
341)
Technicians have been required to pass an EPA certification exam to handle refrigerant since:
A)
July 1, 1992.
B)
November 15, 1993.
C)
November 14, 1994.
D)
November 15, 1995.
Answer:
C
Explanation:
A)
B)
C)
D)
342)
342)
An air conditioner with a thermostatic expansion valve is operating with a condenser saturation
temperature of 95°F and a liquid-line temperature of 92°F. The factory-specified subcooling for
the current operating condition is 10°F. The technician should:
A)
Leave the charge alone because it is cooling even better than factory specifications.
B)
Add charge because the system is undercharged.
C)
Move some of the charge from the low side of the system to the high side of the system to
balance the charge.
D)
Recover charge because the system is overcharged.
Answer:
B
Explanation:
A)
B)
C)
D)
343)
343)
Most air-cooled equipment manufactured today is designed to operate with a:
A)
120°F condenser at 95°F
B)
110°F condenser at 95°F.
C)
105°F condenser at 95°F.
D)
115°F condenser at 95°F.
Answer:
D
Explanation:
A)
B)
C)
D)
89
344)
344)
In general, a system that is undercharged will have:
A)
A high subcooling and a low superheat.
B)
A low subcooling and a low superheat.
C)
A low subcooling and a high superheat.
D)
A high subcooling and a high superheat.
Answer:
C
Explanation:
A)
B)
C)
D)
345)
345)
A ground fault circuit interrupter (GFCI)works by:
A)
Comparing the current on both legs of the circuit.
B)
Measuring the amp draw.
C)
Comparing the voltage to the amp draw.
D)
Measuring the voltage.
Answer:
A
Explanation:
A)
B)
C)
D)
346)
346)
Circuit breakers trip because:
A)
They sense someone receiving an electrical shock.
B)
They reach the end of their programmed operation cycle.
C)
They sense too much current.
D)
They sense an overvoltage condition.
Answer:
C
Explanation:
A)
B)
C)
D)
347)
347)
What use is NM cable suitable for?
A)
Wet or dry locations
B)
Wet or oily locations
C)
Dry locations only
D)
Underground burial
Answer:
C
Explanation:
A)
B)
C)
D)
90
348)
348)
It has been illegal to vent ozone-depleting refrigerants from stationary equipment since:
A)
July 1, 1992.
B)
November 15, 1993.
C)
November 14, 1994.
D)
November 15, 1995.
Answer:
A
Explanation:
A)
B)
C)
D)
349)
349)
It became illegal to vent replacement refrigerants in:
A)
July 1, 1992.
B)
November 15, 1993.
C)
November 14, 1994.
D)
November 15, 1995.
Answer:
D
Explanation:
A)
B)
C)
D)
350)
350)
When using a recovery machine manufactured before November 15, 1993, the recovery level for
Type II systems containing over 200 lb of R-12 refrigerant is:
A)
0 psig.
B)
4 in Hg vacuum.
C)
10 in Hg vacuum.
D)
15 in Hg vacuum.
Answer:
B
Explanation:
A)
B)
C)
D)
351)
351)
Overcharging a system reduces its efficiency by:
A)
Starving the evaporator.
B)
Increasing the operating head pressure and compression ratio.
C)
Increasing the system superheat.
D)
Decreasing the system subcooling.
Answer:
B
Explanation:
A)
B)
C)
D)
91
352)
352)
The fastest method for charging a large system that holds 50 lb of refrigerant is to add:
A)
Vapor into both the suction service valve and king valve with the system off.
B)
Liquid into the suction service valve with the system running.
C)
Liquid into the king valve with the king valve front-seated and the system operating.
D)
Vapor into the suction service valve with the system off.
Answer:
C
Explanation:
A)
B)
C)
D)
353)
353)
To receive an injury due to an electrical arc flash:
A)
Must be unusually susceptible to electronic auras.
B)
The technician must touch an energized electrical source.
C)
Only needs to be standing in the vicinity of the arc flash.
D)
Must complete a circuit with their body.
Answer:
C
Explanation:
A)
B)
C)
D)
354)
354)
What danger is there to using a circuit breaker that is too large for a circuit?
A)
The breaker may be too difficult to turn on.
B)
The voltage supplied to the unit may be too high.
C)
As long as the breaker is at least the minimum required size, it will be safe.
D)
The wire can overheat.
Answer:
D
Explanation:
A)
B)
C)
D)
355)
355)
Liquid refrigerant should always be recovered first from chillers:
A)
To keep from freezing the water in the chiller tubes.
B)
To prevent the removal of refrigerant oil with the refrigerant.
C)
To ensure that all the oil is removed from the compressor.
D)
To ensure the best mixing of refrigerant and water during recovery.
Answer:
A
Explanation:
A)
B)
C)
D)
92
356)
356)
The EPA requires the repair of refrigerant leaks:
A)
Only in systems with a refrigerant charge greater than 50 lb.
B)
Only in systems containing HFC refrigerant.
C)
Only in systems containing CFC refrigerant.
D)
For all types of leaks in all kinds of systems.
Answer:
A
Explanation:
A)
B)
C)
D)
357)
357)
An R-22 system is operating with a liquid pressure of 226 psig (110° saturation temperature). The
specified system subcooling is 5°F. The liquid-line temperature should be:
A)
110°F.
B)
115°F.
C)
105°F.
D)
100°F.
Answer:
C
Explanation:
A)
B)
C)
D)
358)
358)
Why should liquid refrigerant NOT be introduced into an evacuated chiller?
A)
Adding refrigerant would ruin the vacuum.
B)
Liquid charging is slow and chillers hold a lot of refrigerant.
C)
The liquid refrigerant might boil and overheat the water in the chiller.
D)
The liquid can flash at subfreezing temperatures and freeze the water in the chiller tubes.
Answer:
D
Explanation:
A)
B)
C)
D)
359)
359)
How can a noncontact voltage detector be used to indicate a tripped breaker?
A)
The detector will cause the breaker indicating light to come on.
B)
The detector will not show voltage leaving the breaker.
C)
The detector will display "Breaker Off" on its LED display.
D)
The detector will show voltage leaving the breaker.
Answer:
B
Explanation:
A)
B)
C)
D)
93
360)
360)
A person is shocked when:
A)
They touch a grounded wire.
B)
They become part of a complete circuit.
C)
They touch a live wire.
D)
They touch either a live wire or a grounded wire.
Answer:
B
Explanation:
A)
B)
C)
D)
361)
361)
The possible fine for violating the Clean Air Act is:
A)
$37,500 per incident.
B)
$10,000 per incident.
C)
$25,000 per incident.
D)
Life imprisonment.
Answer:
A
Explanation:
A)
B)
C)
D)
362)
362)
As the indoor wet-bulb temperature increases, the required superheat:
A)
Stays the same.
B)
Indoor wet-bulb temperature does not affect superheat.
C)
Decreases.
D)
Increases.
Answer:
D
Explanation:
A)
B)
C)
D)
363)
363)
What advantage does a voltmeter have over a noncontact voltage indicator when testing for
voltage?
A)
They are less expensive.
B)
They can work without touching the energized component.
C)
They connect wirelessly to smartphones.
D)
Voltmeters read the specific voltage level present.
Answer:
D
Explanation:
A)
B)
C)
D)
94
