ESCO Air Conditioning Exam Questions
And Answers
Heat which causes a change in temperature of a substance is called - ANS Sensible heat
Heat added to a substance without a rise in temperature - ANS Latent heat
Heat added to the refrigerant in a vapor state after the evaporation process is called - ANS
Superheat
Scroll compressor move refrigerant by - ANS Involute Spirals
The movement of heat by way of fluid is called - ANS Convection
The movement of heat by direct contact is - ANS Conduction
The standard unit for measuring the quantity of heat in a substance is - ANS BTUs
Refrigerant gives up heat when - ANS It condenses
Why must refrigerant in the suction line be slightly warmer than the saturation temperature? -
ANS Prevent liquid slugging of the compressor
The state of the refrigerant in the suction line should be - ANS Low pressure / Low
temperature vapor
The state of the refrigerant entering the condenser is - ANS High pressure / Highly
superheated vapor
The evaporator - ANS Transfers heat from the refrigerated space to the refrigerant
Which of the following is not a thermodynamic property of refrigerants - ANS Flammability
The sequential order of steps in the vapor compressions process are - ANS Compression,
Condensation, Expansion, Vaporization
If a 30 pound cylinder of reclaimed R 410 a refrigerant has been stored overnight at 70° the
pressure in the cylinder should be approximately - ANS 201 psig
, Fan airflow pressures are usually measured in - ANS Inches of water column
0 pounds per square inch absolute is - ANS A pressure which cannot be further reduced
0 pounds per square inch gauge is - ANS The same as atmospheric pressure
The temperature at which moisture will start to condense from the air is called - ANS Dew
point temperature
A compound pressure gauge measures - ANS Pressure and vacuum
Mechanical shaft seal is necessary on a - ANS Open drive compressor
Liquid slugging is - ANS Liquid refrigerant in the compressor clearance space
The clearance space in reciprocating compressor - ANS Has an effect on compressor
capacity
Which of the following types of air conditioning compressor is most energy-efficient - ANS
Scroll
Which of the following represent the right order for the functions of a condenser - ANS
De-superheat, Condenses, Subcools
Refrigerant R 134a vapor enters the condenser at 124 psi G, 100°F. it leaves as a liquid from
the condenser subcooled 20°F and the pressure will be approximately - ANS 87 psig
There are three basic types of condensers, air-cooled, water-cooled and the _____________
cooled - ANS Evaporative
10 pounds of refrigerant passing through a water cooled condenser will lose 20 BTUs of heat
per pound. If 10 pounds of water passes through the condenser with an entering temperature of
80°F the temperature of the water leaving the condenser is - ANS 100°F
The heat removed from the refrigerant by the condenser is - ANS Both sensible and latent
heat.
An energy recovery ventilator is - ANS an air to air heat exchanger to recover heat
When testing the efficiency of an air-cooled condenser, the refrigerant condensing temperature
should be approximately ________ higher than the entering air temperature - ANS 30°F
And Answers
Heat which causes a change in temperature of a substance is called - ANS Sensible heat
Heat added to a substance without a rise in temperature - ANS Latent heat
Heat added to the refrigerant in a vapor state after the evaporation process is called - ANS
Superheat
Scroll compressor move refrigerant by - ANS Involute Spirals
The movement of heat by way of fluid is called - ANS Convection
The movement of heat by direct contact is - ANS Conduction
The standard unit for measuring the quantity of heat in a substance is - ANS BTUs
Refrigerant gives up heat when - ANS It condenses
Why must refrigerant in the suction line be slightly warmer than the saturation temperature? -
ANS Prevent liquid slugging of the compressor
The state of the refrigerant in the suction line should be - ANS Low pressure / Low
temperature vapor
The state of the refrigerant entering the condenser is - ANS High pressure / Highly
superheated vapor
The evaporator - ANS Transfers heat from the refrigerated space to the refrigerant
Which of the following is not a thermodynamic property of refrigerants - ANS Flammability
The sequential order of steps in the vapor compressions process are - ANS Compression,
Condensation, Expansion, Vaporization
If a 30 pound cylinder of reclaimed R 410 a refrigerant has been stored overnight at 70° the
pressure in the cylinder should be approximately - ANS 201 psig
, Fan airflow pressures are usually measured in - ANS Inches of water column
0 pounds per square inch absolute is - ANS A pressure which cannot be further reduced
0 pounds per square inch gauge is - ANS The same as atmospheric pressure
The temperature at which moisture will start to condense from the air is called - ANS Dew
point temperature
A compound pressure gauge measures - ANS Pressure and vacuum
Mechanical shaft seal is necessary on a - ANS Open drive compressor
Liquid slugging is - ANS Liquid refrigerant in the compressor clearance space
The clearance space in reciprocating compressor - ANS Has an effect on compressor
capacity
Which of the following types of air conditioning compressor is most energy-efficient - ANS
Scroll
Which of the following represent the right order for the functions of a condenser - ANS
De-superheat, Condenses, Subcools
Refrigerant R 134a vapor enters the condenser at 124 psi G, 100°F. it leaves as a liquid from
the condenser subcooled 20°F and the pressure will be approximately - ANS 87 psig
There are three basic types of condensers, air-cooled, water-cooled and the _____________
cooled - ANS Evaporative
10 pounds of refrigerant passing through a water cooled condenser will lose 20 BTUs of heat
per pound. If 10 pounds of water passes through the condenser with an entering temperature of
80°F the temperature of the water leaving the condenser is - ANS 100°F
The heat removed from the refrigerant by the condenser is - ANS Both sensible and latent
heat.
An energy recovery ventilator is - ANS an air to air heat exchanger to recover heat
When testing the efficiency of an air-cooled condenser, the refrigerant condensing temperature
should be approximately ________ higher than the entering air temperature - ANS 30°F
