NATE AIR CONDITIONING
INSTALLATION & SERVICE PRACTICE
QUESTIONS & ANSWERS 100% SOLVED
A good evacuation of a refrigerant circuit to remove non-condensables will help insure:
A.) higher condensing temperatures
B.) higher suction pressures
C.) low suction line pressure drop
D.) higher efficiency and capacity - ANSWERD.) higher efficiency and capacity
A liquid line with a low to normal high side pressure is an indication of:
A.) An overcharged system
B.) An undercharged system
C.) Air in the system
D.) A restricted filter-drier - ANSWERB.) An undercharged system
Air and water are directed counterflow so as to:
A.) average flow rate
B.) gain the greatest amount of heat transfer
C.) reach the lowest apparatus dew point
D.) control the humidity - ANSWERB.) gain the greatest amount of heat transfer
Which of the following applications is not a mechanical cooling system?
A.) Cascade system
B.) Reciprocating compression system
C.) Evaporative cooling
D.) Centrifugal compression system - ANSWERC.) Evaporative cooling
Which of the following is the correct sequence of work?
A.) Attach the gauge manifold, recover refrigerant, replace the filter core, evacuate the
system, recharge the system.
B.) Recover the refrigerant, evacuate the system, replace the filter core, recharge the
system.
C.) Attach the gauge manifold, evacuate the system, replace the filter core, recover the
refrigerant, recharge the system.
, D.) Attach the gauge manifold, recharge the system, evacuate the system, replace the
filter core. - ANSWERA.) Attach the gauge manifold, recover refrigerant, replace the
filter core, evacuate the system, recharge the system.
As the pressure on the liquid line is increased, the vaporization temperature of the
liquid:
A.) decreases
B.) increases
C.) remains unchanged
D.) varies - ANSWERB.) increases
An oil separator must be mounted:
A.) level
B.) below the compressor crankcase
C.) above the compressor crankcase
D.) in the suction line - ANSWERA.) level
Which of the following metering devices controls evaporator pressure?
A.) Thermostatic expansion valve
B.) Fixed orifice
C.) Low side float
D.) None of these - ANSWERD.) None of these
The purpose of the external equalizer on the thermostatic expansion valve is:
A.) to equalize evaporator pressure drop with respect to the TEV
B.) to equalize the evaporator pressure drop
C.) to help prevent liquid flood back
D.) to allow the high side pressure to equalize to the low side when the compressor
cycles off - ANSWERA.) to equalize evaporator pressure drop with respect to the TEV
The higher the MERV rating of a filter-drier, the
A.) more efficient the drier is at absorbing moisture
B.) less efficient the drier is at absorbing moisture
C.) smaller the particles the filter can entrap
D.) MERV does not apply to filter-driers - ANSWERD.) MERV does not apply to filter
driers
Zeolite is used with:
A.) refrigerant filter-driers
B.) HEPA filters
C.) pipe threads
D.) solder - ANSWERA.) refrigerant filter-driers
Vacuum pressures are measured in:
A.) microns
B.) millimeters of mercury
INSTALLATION & SERVICE PRACTICE
QUESTIONS & ANSWERS 100% SOLVED
A good evacuation of a refrigerant circuit to remove non-condensables will help insure:
A.) higher condensing temperatures
B.) higher suction pressures
C.) low suction line pressure drop
D.) higher efficiency and capacity - ANSWERD.) higher efficiency and capacity
A liquid line with a low to normal high side pressure is an indication of:
A.) An overcharged system
B.) An undercharged system
C.) Air in the system
D.) A restricted filter-drier - ANSWERB.) An undercharged system
Air and water are directed counterflow so as to:
A.) average flow rate
B.) gain the greatest amount of heat transfer
C.) reach the lowest apparatus dew point
D.) control the humidity - ANSWERB.) gain the greatest amount of heat transfer
Which of the following applications is not a mechanical cooling system?
A.) Cascade system
B.) Reciprocating compression system
C.) Evaporative cooling
D.) Centrifugal compression system - ANSWERC.) Evaporative cooling
Which of the following is the correct sequence of work?
A.) Attach the gauge manifold, recover refrigerant, replace the filter core, evacuate the
system, recharge the system.
B.) Recover the refrigerant, evacuate the system, replace the filter core, recharge the
system.
C.) Attach the gauge manifold, evacuate the system, replace the filter core, recover the
refrigerant, recharge the system.
, D.) Attach the gauge manifold, recharge the system, evacuate the system, replace the
filter core. - ANSWERA.) Attach the gauge manifold, recover refrigerant, replace the
filter core, evacuate the system, recharge the system.
As the pressure on the liquid line is increased, the vaporization temperature of the
liquid:
A.) decreases
B.) increases
C.) remains unchanged
D.) varies - ANSWERB.) increases
An oil separator must be mounted:
A.) level
B.) below the compressor crankcase
C.) above the compressor crankcase
D.) in the suction line - ANSWERA.) level
Which of the following metering devices controls evaporator pressure?
A.) Thermostatic expansion valve
B.) Fixed orifice
C.) Low side float
D.) None of these - ANSWERD.) None of these
The purpose of the external equalizer on the thermostatic expansion valve is:
A.) to equalize evaporator pressure drop with respect to the TEV
B.) to equalize the evaporator pressure drop
C.) to help prevent liquid flood back
D.) to allow the high side pressure to equalize to the low side when the compressor
cycles off - ANSWERA.) to equalize evaporator pressure drop with respect to the TEV
The higher the MERV rating of a filter-drier, the
A.) more efficient the drier is at absorbing moisture
B.) less efficient the drier is at absorbing moisture
C.) smaller the particles the filter can entrap
D.) MERV does not apply to filter-driers - ANSWERD.) MERV does not apply to filter
driers
Zeolite is used with:
A.) refrigerant filter-driers
B.) HEPA filters
C.) pipe threads
D.) solder - ANSWERA.) refrigerant filter-driers
Vacuum pressures are measured in:
A.) microns
B.) millimeters of mercury
