AMMONIA REFRIGERATION FINAL EXAM QUESTIONS AND
CORRECT ANSWERS LATEST UPDATE!!
Convection is the transfer of ____ - ANSWER heat through a material or
substance
Radiation is the ____ - ANSWER projection of heat like the heat radiated by the
sun or by an open flame
T or F: Heat is always on the move, traveling only in one direction and always
from hot to cold - ANSWER false
What are two methods of heat transfer? - ANSWER conduction and convection
What are two basic forms of refrigeration systems? - ANSWER direct expansion
and gravity flooded
T or F: Conduction is the heat transferred due to the temperature being different
on one side of a room than the other like the heat rising in a room - ANSWER true
T or F: A basic refrigeration system consists of an expansion device, an
evaporator, a compressor, and a condenser connected by a series of pipes -
ANSWER true
T or F: Compression occurs as the ammonia refrigerant passes through the
evaporator - ANSWER false
T or F: The high side includes all components between the pressure reduction
device outlet to a point inside the compressor - ANSWER false
Heat contained in the area to be cooled and absorbed by the ammonia refrigerant
as it passes through the evaporator is called? - ANSWER the load
The low side of an ammonia refrigeration system consists of ... - ANSWER the
pressure reduction device and the condenser
T or F: Expansion occurs as the refrigerant flows through the compressor -
ANSWER false
, T or F: When a hand expansion valve is opened, pressure behind the valve forces
liquid ammonia through a small opening causing a deliberate pressure drop to
occur - ANSWER false
T or F: Evaporation takes place as the ammonia refrigerant flows through the
compressor - ANSWER false
T or F: The evaporation process is completed when the ammonia has passed
through the evaporator - ANSWER true
Absolute pressure is the pressure read by a gauge, plus the ____ atmospheric
pressure - ANSWER ambient
T or F: A pumped liquid, or re-circulation single stage system consists of a
receiver, a king valve, a pressure reduction device, an evaporator, a compressor,
a condenser, a vessel, a pump and an additional flow metering device - ANSWER
true
Where is the worst place to have a leak in an ammonia refrigeration system? -
ANSWER high pressure liquid
How many BTUs does it take to convert 1 lb of saturated ammonia to 1 lb of
saturated gas? - ANSWER 561
How many BTUs does it take to convert 1 lb of liquid water at 212° to steam as
212°F - ANSWER 970
How many BTUs does it take to melt 1 lb of ice into water at 32°F - ANSWER 144
What is specific heat ? - ANSWER the amount of heat transferred to change 1 lb
of a substance 1°F
What is the IDLH for ammonia? - ANSWER 300 PPM
Under what conditions may some synthetic refrigerants become toxic? -
ANSWER contact with an open flame
100°C equals - ANSWER 212°F
Copper tubing is never used with? - ANSWER R717
A "King" valve is a ____ - ANSWER receiver inlet valve
The centrifugal compressor is ____ a positive displacement compressor -
ANSWER not
CORRECT ANSWERS LATEST UPDATE!!
Convection is the transfer of ____ - ANSWER heat through a material or
substance
Radiation is the ____ - ANSWER projection of heat like the heat radiated by the
sun or by an open flame
T or F: Heat is always on the move, traveling only in one direction and always
from hot to cold - ANSWER false
What are two methods of heat transfer? - ANSWER conduction and convection
What are two basic forms of refrigeration systems? - ANSWER direct expansion
and gravity flooded
T or F: Conduction is the heat transferred due to the temperature being different
on one side of a room than the other like the heat rising in a room - ANSWER true
T or F: A basic refrigeration system consists of an expansion device, an
evaporator, a compressor, and a condenser connected by a series of pipes -
ANSWER true
T or F: Compression occurs as the ammonia refrigerant passes through the
evaporator - ANSWER false
T or F: The high side includes all components between the pressure reduction
device outlet to a point inside the compressor - ANSWER false
Heat contained in the area to be cooled and absorbed by the ammonia refrigerant
as it passes through the evaporator is called? - ANSWER the load
The low side of an ammonia refrigeration system consists of ... - ANSWER the
pressure reduction device and the condenser
T or F: Expansion occurs as the refrigerant flows through the compressor -
ANSWER false
, T or F: When a hand expansion valve is opened, pressure behind the valve forces
liquid ammonia through a small opening causing a deliberate pressure drop to
occur - ANSWER false
T or F: Evaporation takes place as the ammonia refrigerant flows through the
compressor - ANSWER false
T or F: The evaporation process is completed when the ammonia has passed
through the evaporator - ANSWER true
Absolute pressure is the pressure read by a gauge, plus the ____ atmospheric
pressure - ANSWER ambient
T or F: A pumped liquid, or re-circulation single stage system consists of a
receiver, a king valve, a pressure reduction device, an evaporator, a compressor,
a condenser, a vessel, a pump and an additional flow metering device - ANSWER
true
Where is the worst place to have a leak in an ammonia refrigeration system? -
ANSWER high pressure liquid
How many BTUs does it take to convert 1 lb of saturated ammonia to 1 lb of
saturated gas? - ANSWER 561
How many BTUs does it take to convert 1 lb of liquid water at 212° to steam as
212°F - ANSWER 970
How many BTUs does it take to melt 1 lb of ice into water at 32°F - ANSWER 144
What is specific heat ? - ANSWER the amount of heat transferred to change 1 lb
of a substance 1°F
What is the IDLH for ammonia? - ANSWER 300 PPM
Under what conditions may some synthetic refrigerants become toxic? -
ANSWER contact with an open flame
100°C equals - ANSWER 212°F
Copper tubing is never used with? - ANSWER R717
A "King" valve is a ____ - ANSWER receiver inlet valve
The centrifugal compressor is ____ a positive displacement compressor -
ANSWER not
