REFRIGERATION ESCO QUESTIONS AND
ANSWERS
heat which causes a change in temperature of a substance is called - CORRECT
ANSWER- sensible heat
heat which causes a change in state of a material without a change in temperature is
called - CORRECT ANSWER- latent heat
heat which is added to a vapor after the change of state occurs is called - CORRECT
ANSWER- superheat
heat can travel by - CORRECT ANSWER- conduction, convection, radiation
the movement a heat by the way of a fluid or air is called - CORRECT ANSWER-
convection
the movement of heat by direct contact is called - CORRECT ANSWER- conduction
the standard unit for measuring the quantity of heat in a substance is - CORRECT
ANSWER- the british thermal unit
a refrigerant gives up heat when - CORRECT ANSWER- it condenses
it is desirable for refrigerant in the suction line to be slighlty superheat in order to -
CORRECT ANSWER- insure liquid refrigerant does not enter the compressor
the state of the refrigerant in the suction line should be - CORRECT ANSWER- low
pressure/ low temperature vapor
the state of the refrigerant entering the condenser is - CORRECT ANSWER- high
pressure/ highly superheated vapor
the evaporator - CORRECT ANSWER- transfers heat from the refrigerated space to the
refrigerant
thermodynamic properties of refrigerants - CORRECT ANSWER- critical point,
enthalpy, and saturation point
the sequential order of steps in the vapor- compression process are - CORRECT
ANSWER- compression, condensation, expansion, and vaporization
If a 30 pound cylinder of reclaimed R410A refrigerant has been stored over night at 70
degrees, the pressure in the cylinder should be approx - CORRECT ANSWER- 201
psig
, Zero psia is - CORRECT ANSWER- A pressure which cannot be further reduced
Zero psig is - CORRECT ANSWER- the same as atmospheric pressure
the temperature at which moisture will start to condense from the air is called -
CORRECT ANSWER- dew point temperature
a compound pressure gauge measures - CORRECT ANSWER- pressure and vacuum
the main function of the condenser is to - CORRECT ANSWER- remove heat from the
refrigerant
the heat removed from the refrigerant by the condenser is - CORRECT ANSWER- both
sensible and latent heat
in the evaporator - CORRECT ANSWER- latent heat is transferred from the refrigerated
space to the refrigerant
an overcharge of refrigerant will cause - CORRECT ANSWER- increased head
pressure
what is the recommended residential indoor relative humidity for the summer -
CORRECT ANSWER- 50%
liquid slugging is - CORRECT ANSWER- liquid refrigerant in the compressor clearance
space
the clearance space in a reciprocating compressor - CORRECT ANSWER- Has no
effect on compressor capacity
Air conditioning compressor that is most energy efficient - CORRECT ANSWER-
centrifugal
the main function of the condenser is to - CORRECT ANSWER- remove heat from the
refrigerant
refrigerant r134a vapor enters the condenser at 124 psig at 100, it leaves the condenser
at 80 degrees, its pressure will approx be - CORRECT ANSWER- 124 psig
there are three basic types of condensers - CORRECT ANSWER- air cooled
water cooled
evaporative cooled
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
ANSWERS
heat which causes a change in temperature of a substance is called - CORRECT
ANSWER- sensible heat
heat which causes a change in state of a material without a change in temperature is
called - CORRECT ANSWER- latent heat
heat which is added to a vapor after the change of state occurs is called - CORRECT
ANSWER- superheat
heat can travel by - CORRECT ANSWER- conduction, convection, radiation
the movement a heat by the way of a fluid or air is called - CORRECT ANSWER-
convection
the movement of heat by direct contact is called - CORRECT ANSWER- conduction
the standard unit for measuring the quantity of heat in a substance is - CORRECT
ANSWER- the british thermal unit
a refrigerant gives up heat when - CORRECT ANSWER- it condenses
it is desirable for refrigerant in the suction line to be slighlty superheat in order to -
CORRECT ANSWER- insure liquid refrigerant does not enter the compressor
the state of the refrigerant in the suction line should be - CORRECT ANSWER- low
pressure/ low temperature vapor
the state of the refrigerant entering the condenser is - CORRECT ANSWER- high
pressure/ highly superheated vapor
the evaporator - CORRECT ANSWER- transfers heat from the refrigerated space to the
refrigerant
thermodynamic properties of refrigerants - CORRECT ANSWER- critical point,
enthalpy, and saturation point
the sequential order of steps in the vapor- compression process are - CORRECT
ANSWER- compression, condensation, expansion, and vaporization
If a 30 pound cylinder of reclaimed R410A refrigerant has been stored over night at 70
degrees, the pressure in the cylinder should be approx - CORRECT ANSWER- 201
psig
, Zero psia is - CORRECT ANSWER- A pressure which cannot be further reduced
Zero psig is - CORRECT ANSWER- the same as atmospheric pressure
the temperature at which moisture will start to condense from the air is called -
CORRECT ANSWER- dew point temperature
a compound pressure gauge measures - CORRECT ANSWER- pressure and vacuum
the main function of the condenser is to - CORRECT ANSWER- remove heat from the
refrigerant
the heat removed from the refrigerant by the condenser is - CORRECT ANSWER- both
sensible and latent heat
in the evaporator - CORRECT ANSWER- latent heat is transferred from the refrigerated
space to the refrigerant
an overcharge of refrigerant will cause - CORRECT ANSWER- increased head
pressure
what is the recommended residential indoor relative humidity for the summer -
CORRECT ANSWER- 50%
liquid slugging is - CORRECT ANSWER- liquid refrigerant in the compressor clearance
space
the clearance space in a reciprocating compressor - CORRECT ANSWER- Has no
effect on compressor capacity
Air conditioning compressor that is most energy efficient - CORRECT ANSWER-
centrifugal
the main function of the condenser is to - CORRECT ANSWER- remove heat from the
refrigerant
refrigerant r134a vapor enters the condenser at 124 psig at 100, it leaves the condenser
at 80 degrees, its pressure will approx be - CORRECT ANSWER- 124 psig
there are three basic types of condensers - CORRECT ANSWER- air cooled
water cooled
evaporative cooled
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
