HVAC Test with All Correct & 100% Verified Answers|
Actual Complete Exam |Already Graded A+
There is insufficient heat in the cab. Technician A says that air in the cooling system could be the
cause. Technician B says a stuck water valve could be the cause. Who is right? ✔Correct Answer-
Both A and B
The heater blower is inoperative. Technician A says that a defective blower switch could be the
cause. Technician B says that a defective blower resistor could be the cause. Who is right?
✔Correct Answer-Technician A only
Which of the following best describes the system condition when no bubbles are found in the sight
glass on the receiver/drier ✔Correct Answer-system is overcharged, system has no refrigerant,
and system is operating properly
The driver reports that the air from the outlets is only slightly cool. Both the high side and low side
gauge readings are normal, and the sight glass is clear. Technician A says there may be air in the
system. Technician B says that the expansion valve may be stuck closed. Who Is right? ✔Correct
Answer-Both A and B
The A/C compressor cycles rapidy, and air com- ing from the outlets is only slightly cool. Technician A
says the problem could be a low refrigerant charge. Technician B says the problem could be a
defective thermostatic switch. Who is right? ✔Correct Answer-Both A and B
The driver complains that the heater output is not warm enough. Technician A says the cause could
be a faulty thermostat. Technician B says the water control valve could be bad. Who is right?
✔Correct Answer-Both A and B
Technician a says moisture can only be removed by pulling a vacuum on the system for at least 30
minutes after recovering the refrigerant charge. Technician B says that moisture in the system can be
removed by venting through the low side with the A/C turned off. Who is right? ✔Correct
Answer-Technician A only
The air conditioning operates normally for about a half-hour. Afterwards, the Air temperature from
the outlet rises. Technician a says that there could be a defective high blower relay. Technician B says
that the evaporator could be icing up. Who is right? ✔Correct Answer-Technician B only
There are bubbles in the site glass after the system has been running for a brief period of time.
Which of the following could be the problem? ✔Correct Answer-Insufficient refrigerant
Technician A says that unique fittings are required on the A/C system as well as service tools for each
different type of refrigerant. Technician B says that the doctors can be used to convert his
recovery/recycling equipment for use with any system containing any refrigerant. Who is right?
✔Correct Answer-Technician A only
And A/C system has been evacuated. After the vacuum pump is turned off, within five minutes, the
low side gauge reading creeps towards zero. Which of these is the most likely cause? ✔Correct
Answer-leak in the A/C system
, Technician A says a thermometer and pressure gauge are necessary to check a refrigerant container
for non-Condensible gases(air). Technician B says excessive non-condensable gases in the container
may be vented into the atmosphere. Who is right? ✔Correct Answer-Technician A only
With the A/C running at the 'MAX' setting, a thermometer reading the temperature coming from the
vent nearest the evaporator core swings from 32° F to 42° F. Technician A says this is normal and that
the temperature swings coincide with the cycling of the compressor. Tech be says that the cycling
indicates ice is forming and melting on the evaporator core. Who is right? ✔Correct Answer-
Technician A only
The compressor makes a rattling noise when it is operating. Technician A says the problem could be
the a slipping belt. Technician B says the problem could be a defective compressor shaft bearing.
Who is right? ✔Correct Answer-Both A and B
And electric cooling fan fails to engage. Technician A says that the problem could be a defective
coolant temperature switch. Technician B says that the thermostat may be stuck open. Who is right?
✔Correct Answer-Both A and B
Technician A says that the binary switch provides low system pressure protection. Technician B says
that the trinary switch provides high system pressure protection. Who is right? ✔Correct Answer-
Both A and B
Technician A says that evacuating an A/C system will remove air and moisture from the system.
Technician B says that evacuating an A/C system will remove debris from the system. Who is right?
✔Correct Answer-Technician A only
A technician inspecting an A/C system finds that the high side pressure is above specs. All of the
following can cause this problem except: ✔Correct Answer-Defective thermal limiter
Technician A says that moisture in an A/C system can freeze in the expansion valve and stop the
system from cooling. Technician B says that moisture in the A/C system will react with our 12 to form
an acid that can cause corrosion. Who is right? ✔Correct Answer-Both A and B
The refrigerant in the receiver dryer is a: ✔Correct Answer-Liquid at high-pressure
Recovery/recycling equipment must have shut off valves located within 12-in. (30 cm) of the hoses'
service ends so that: ✔Correct Answer-Refrigerant leakage can be kept to a minimum
Technician A says that the liquid refrigerant changes to a vapor in the condenser. Technician B says
the refrigerant vapor changes to a liquid in the evaporator. Who is right? ✔Correct Answer-
Neither A or B
The operation of the thermostatic switch depends on the temperature of the: ✔Correct Answer-
Evaporator
A technician finds a low pressure reading on the low side, accompanied by heavy frost accumulation
on the inlet side of the thermostatic expansion valve. (TXV) What would this indicate? ✔Correct
Answer-Clogged screen on the TXV
Actual Complete Exam |Already Graded A+
There is insufficient heat in the cab. Technician A says that air in the cooling system could be the
cause. Technician B says a stuck water valve could be the cause. Who is right? ✔Correct Answer-
Both A and B
The heater blower is inoperative. Technician A says that a defective blower switch could be the
cause. Technician B says that a defective blower resistor could be the cause. Who is right?
✔Correct Answer-Technician A only
Which of the following best describes the system condition when no bubbles are found in the sight
glass on the receiver/drier ✔Correct Answer-system is overcharged, system has no refrigerant,
and system is operating properly
The driver reports that the air from the outlets is only slightly cool. Both the high side and low side
gauge readings are normal, and the sight glass is clear. Technician A says there may be air in the
system. Technician B says that the expansion valve may be stuck closed. Who Is right? ✔Correct
Answer-Both A and B
The A/C compressor cycles rapidy, and air com- ing from the outlets is only slightly cool. Technician A
says the problem could be a low refrigerant charge. Technician B says the problem could be a
defective thermostatic switch. Who is right? ✔Correct Answer-Both A and B
The driver complains that the heater output is not warm enough. Technician A says the cause could
be a faulty thermostat. Technician B says the water control valve could be bad. Who is right?
✔Correct Answer-Both A and B
Technician a says moisture can only be removed by pulling a vacuum on the system for at least 30
minutes after recovering the refrigerant charge. Technician B says that moisture in the system can be
removed by venting through the low side with the A/C turned off. Who is right? ✔Correct
Answer-Technician A only
The air conditioning operates normally for about a half-hour. Afterwards, the Air temperature from
the outlet rises. Technician a says that there could be a defective high blower relay. Technician B says
that the evaporator could be icing up. Who is right? ✔Correct Answer-Technician B only
There are bubbles in the site glass after the system has been running for a brief period of time.
Which of the following could be the problem? ✔Correct Answer-Insufficient refrigerant
Technician A says that unique fittings are required on the A/C system as well as service tools for each
different type of refrigerant. Technician B says that the doctors can be used to convert his
recovery/recycling equipment for use with any system containing any refrigerant. Who is right?
✔Correct Answer-Technician A only
And A/C system has been evacuated. After the vacuum pump is turned off, within five minutes, the
low side gauge reading creeps towards zero. Which of these is the most likely cause? ✔Correct
Answer-leak in the A/C system
, Technician A says a thermometer and pressure gauge are necessary to check a refrigerant container
for non-Condensible gases(air). Technician B says excessive non-condensable gases in the container
may be vented into the atmosphere. Who is right? ✔Correct Answer-Technician A only
With the A/C running at the 'MAX' setting, a thermometer reading the temperature coming from the
vent nearest the evaporator core swings from 32° F to 42° F. Technician A says this is normal and that
the temperature swings coincide with the cycling of the compressor. Tech be says that the cycling
indicates ice is forming and melting on the evaporator core. Who is right? ✔Correct Answer-
Technician A only
The compressor makes a rattling noise when it is operating. Technician A says the problem could be
the a slipping belt. Technician B says the problem could be a defective compressor shaft bearing.
Who is right? ✔Correct Answer-Both A and B
And electric cooling fan fails to engage. Technician A says that the problem could be a defective
coolant temperature switch. Technician B says that the thermostat may be stuck open. Who is right?
✔Correct Answer-Both A and B
Technician A says that the binary switch provides low system pressure protection. Technician B says
that the trinary switch provides high system pressure protection. Who is right? ✔Correct Answer-
Both A and B
Technician A says that evacuating an A/C system will remove air and moisture from the system.
Technician B says that evacuating an A/C system will remove debris from the system. Who is right?
✔Correct Answer-Technician A only
A technician inspecting an A/C system finds that the high side pressure is above specs. All of the
following can cause this problem except: ✔Correct Answer-Defective thermal limiter
Technician A says that moisture in an A/C system can freeze in the expansion valve and stop the
system from cooling. Technician B says that moisture in the A/C system will react with our 12 to form
an acid that can cause corrosion. Who is right? ✔Correct Answer-Both A and B
The refrigerant in the receiver dryer is a: ✔Correct Answer-Liquid at high-pressure
Recovery/recycling equipment must have shut off valves located within 12-in. (30 cm) of the hoses'
service ends so that: ✔Correct Answer-Refrigerant leakage can be kept to a minimum
Technician A says that the liquid refrigerant changes to a vapor in the condenser. Technician B says
the refrigerant vapor changes to a liquid in the evaporator. Who is right? ✔Correct Answer-
Neither A or B
The operation of the thermostatic switch depends on the temperature of the: ✔Correct Answer-
Evaporator
A technician finds a low pressure reading on the low side, accompanied by heavy frost accumulation
on the inlet side of the thermostatic expansion valve. (TXV) What would this indicate? ✔Correct
Answer-Clogged screen on the TXV
