HVAC EXCELLENCE TEST QUESTIONS AND ANSWERS
100% SOLVED | VERIFIED
/Heat which causes a change in temperature of a substance is called - Answer-sensible
heat,
/.Heat added to a substance without a rise in temperature; (example: liquid refrigerant to
gas) this process la called? - Answer-latent heat
/.Heat added to the refrigerant in vapor state after the evaporation process is called, -
Answer-superheat
/.A scroll compressor moves refrigerant by means of; - Answer-involute spirals
/.The movement of heat by way of fluid or is called; air - Answer-convection
/.The movement of heat through a solid object is called; - Answer-radiation
/.The standard unit for measuring the quantity of heat in a substance is - Answer-British
Thermal Unit
/.A refrigerant gives up heat when it; - Answer-it condenses
/.Why must refrigerant in the suction line be slightly warmer than the saturation
temperature? - Answer-prevent liquid slugging of the compressor.
/.It is desirable for refrigerant in the suction line to be slightly superheated in order to; -
Answer-insure liquid refrigerant does not enter the compressor.,
/.The state of the refrigerant in the suction line should be - Answer-low pressure/ low
temperature vapor
/.The state of the refrigerant entering the condenser is - Answer-High Pressure/ Highly
Superheated Vapor
/.The Evaporator - Answer-Transfers heat from the refrigerated space to the refrigerant
/.The Evaporator - Answer-Transfers heat from the refrigerated space to the refrigerant
/.Which of the following is not a Thermodynamic Property of refrigerant - Answer-
Flammability
/.The sequential order of steps in the vapor-compression process are: - Answer-
Compression, Condensation, Expansion, Vaporization
, /.If a 30 lb container of $-410A refrigerant has been stored over night at 70 degrees F,
the pressure in the cylinder should be approximately - Answer-201 Degrees Faranheit
/.Fan Airflow pressures are usually measured in - Answer-Inches of water column
/.Zero Psia (pounds per square inch absolute) is - Answer-a pressure which cannot be
further reduced
/.Zero Psig (pounds per square inch gauge) - Answer-The same as atmospheric
pressure
/.The Temperature at which moisture will start to condense from the air is called -
Answer-Dew Point Temperature
/.A Compound pressure gauge measures - Answer-Pressure and Vacuum
/.A Mechanical shaft seal is necesssary on a - Answer-Open drive compressor
/.Liquid slugging is - Answer-Liquid refrigerant in the compressor clearance space
/.The Clearance space in a reciprocating compressor - Answer-has an effect on
compressor capacity
/.Which of the following types of air conditioning compressors is more efficient - Answer-
Centrifugal
/.Which of the following represnet the right order for the functionsof a condenser -
Answer-De-Superheats, Condenses, and Sub-cools
/.Refrigerant R-134a vapor enters the condenser at 124psig, 100 degrees faranheit, It
leaves as a liquid from the condenser, sub-cooled 20 degrees faranheit, and the
pressure will be approximately - Answer-124 psig
/.There are 3 basic types of condensers, air cooled, water cooled, and - Answer-
evaporative cooled
/.10 lbs of refrigerant passing through a water cooled condenser will lose 20 BTU of
heat/ pound. If 10#'s of water passes through the condenser with an entering temp of 80
degrees, the temp of the water leaving the condenser is - Answer-100 degrees faranheit
/.The heat removed from the refrigerant by the condenser is - Answer-both sensible and
latent heat
/.An energy recovery ventilator is - Answer-an air to air heat exhanger to recover heat
100% SOLVED | VERIFIED
/Heat which causes a change in temperature of a substance is called - Answer-sensible
heat,
/.Heat added to a substance without a rise in temperature; (example: liquid refrigerant to
gas) this process la called? - Answer-latent heat
/.Heat added to the refrigerant in vapor state after the evaporation process is called, -
Answer-superheat
/.A scroll compressor moves refrigerant by means of; - Answer-involute spirals
/.The movement of heat by way of fluid or is called; air - Answer-convection
/.The movement of heat through a solid object is called; - Answer-radiation
/.The standard unit for measuring the quantity of heat in a substance is - Answer-British
Thermal Unit
/.A refrigerant gives up heat when it; - Answer-it condenses
/.Why must refrigerant in the suction line be slightly warmer than the saturation
temperature? - Answer-prevent liquid slugging of the compressor.
/.It is desirable for refrigerant in the suction line to be slightly superheated in order to; -
Answer-insure liquid refrigerant does not enter the compressor.,
/.The state of the refrigerant in the suction line should be - Answer-low pressure/ low
temperature vapor
/.The state of the refrigerant entering the condenser is - Answer-High Pressure/ Highly
Superheated Vapor
/.The Evaporator - Answer-Transfers heat from the refrigerated space to the refrigerant
/.The Evaporator - Answer-Transfers heat from the refrigerated space to the refrigerant
/.Which of the following is not a Thermodynamic Property of refrigerant - Answer-
Flammability
/.The sequential order of steps in the vapor-compression process are: - Answer-
Compression, Condensation, Expansion, Vaporization
, /.If a 30 lb container of $-410A refrigerant has been stored over night at 70 degrees F,
the pressure in the cylinder should be approximately - Answer-201 Degrees Faranheit
/.Fan Airflow pressures are usually measured in - Answer-Inches of water column
/.Zero Psia (pounds per square inch absolute) is - Answer-a pressure which cannot be
further reduced
/.Zero Psig (pounds per square inch gauge) - Answer-The same as atmospheric
pressure
/.The Temperature at which moisture will start to condense from the air is called -
Answer-Dew Point Temperature
/.A Compound pressure gauge measures - Answer-Pressure and Vacuum
/.A Mechanical shaft seal is necesssary on a - Answer-Open drive compressor
/.Liquid slugging is - Answer-Liquid refrigerant in the compressor clearance space
/.The Clearance space in a reciprocating compressor - Answer-has an effect on
compressor capacity
/.Which of the following types of air conditioning compressors is more efficient - Answer-
Centrifugal
/.Which of the following represnet the right order for the functionsof a condenser -
Answer-De-Superheats, Condenses, and Sub-cools
/.Refrigerant R-134a vapor enters the condenser at 124psig, 100 degrees faranheit, It
leaves as a liquid from the condenser, sub-cooled 20 degrees faranheit, and the
pressure will be approximately - Answer-124 psig
/.There are 3 basic types of condensers, air cooled, water cooled, and - Answer-
evaporative cooled
/.10 lbs of refrigerant passing through a water cooled condenser will lose 20 BTU of
heat/ pound. If 10#'s of water passes through the condenser with an entering temp of 80
degrees, the temp of the water leaving the condenser is - Answer-100 degrees faranheit
/.The heat removed from the refrigerant by the condenser is - Answer-both sensible and
latent heat
/.An energy recovery ventilator is - Answer-an air to air heat exhanger to recover heat
