NJ Refrigeration Blue Seal 2-C sample questions
A cylinder area of 38.5" sq. and pressure of 121 psi. What is the piston diameter?
A. 1'
B. 17"
C. 7"
D. 4658.5 - ANS -C. 7"
D = sq. root (A / .7854)
\Ammonia R-717 is considered one of many toxic refrigerants and is classified by its toxicity and flammability, which ranks
it as a:
A. group two refrigerant
B. R5
C. R1
D. ANSI 7 - ANS -A. group two refrigerant
\As suction pressure in a recip compressor increases, and the HP decreases, compressor capacity:
A. increases
B. fluctuates
C. decreases
D. stays the same - ANS -A. increases
\As the condensing temp of a centrifugal system decreases, the power req'd by the compressor:
A. fluctuates
B. decreases
C. increases
,D. remains the same - ANS -B. decreases
\As the specific gravity of calcium chloride brine increases:
A. the density decreases
B. the density increases
C. the freeze point decreases
D. the freeze point decreases - ANS -A. the density decreases
\Heat transfer that occurs primarily by conduction is used for what type of process?
A. indirect contact
B. immersion
C. air blast
D. absorber - ANS -B. immersion
\How many BTUs must be removed to lower the temp of 2000 lbs of ice from 32°F to 29°F?
A. 3500 BTUs
B. 6000 BTUs
C. 3000 BTUs
D. 1500 BTUs - ANS -C. 3000 BTUs
\How many months experience in a flammable, highly toxic, or toxic refrigerant plant is needed in order to qualify for a 2-C
license?
A. 6 months
B. 3 months
C. 1 month
D. 9 months - ANS -B. 3 months
\If a compound gauge reads 15" Hg, what is the equivalent in psig?
A. -7.5 psig
, B. 30 psig
C. 7.5 psig
D. -15 psig - ANS -C. 7.5 psig
\If there were a sudden drop in temp in the cooling tower of a lithium bromide absorption system, what would happen?
A. crystallization in the system
B. high head pressure in the absorber
C. low pressure in the system
D. low head pressure in the absorber - ANS -A. crystallization in the system
\If you had a compressor operating with a four pole motor at 150hp, 120v, and 60 cycles per sec, what would its RPMs
be?
A. 1800 RPMs
B. 900 RPMs
C. 1600 RPMs
D. 3600 RPMs - ANS -A. 1800 RPMs
RPM = Hz (2/p) 60
\In a refrigeration system using a high-side float, which of the following would control its operation?
A. the evaporator & receiver
B. the accumulator
C. the condenser & receiver
D. the evaporator & condenser - ANS -C. the condenser & receiver
\In a refrigeration system, what effect would an increase in load on the evaporator have on the system?
A. system stays the same
B. suction pressure increases while HP decreases
C. the condenser floods
D. suction pressure increases while HP increases - ANS -B. suction pressure increases while HP decreases
A cylinder area of 38.5" sq. and pressure of 121 psi. What is the piston diameter?
A. 1'
B. 17"
C. 7"
D. 4658.5 - ANS -C. 7"
D = sq. root (A / .7854)
\Ammonia R-717 is considered one of many toxic refrigerants and is classified by its toxicity and flammability, which ranks
it as a:
A. group two refrigerant
B. R5
C. R1
D. ANSI 7 - ANS -A. group two refrigerant
\As suction pressure in a recip compressor increases, and the HP decreases, compressor capacity:
A. increases
B. fluctuates
C. decreases
D. stays the same - ANS -A. increases
\As the condensing temp of a centrifugal system decreases, the power req'd by the compressor:
A. fluctuates
B. decreases
C. increases
,D. remains the same - ANS -B. decreases
\As the specific gravity of calcium chloride brine increases:
A. the density decreases
B. the density increases
C. the freeze point decreases
D. the freeze point decreases - ANS -A. the density decreases
\Heat transfer that occurs primarily by conduction is used for what type of process?
A. indirect contact
B. immersion
C. air blast
D. absorber - ANS -B. immersion
\How many BTUs must be removed to lower the temp of 2000 lbs of ice from 32°F to 29°F?
A. 3500 BTUs
B. 6000 BTUs
C. 3000 BTUs
D. 1500 BTUs - ANS -C. 3000 BTUs
\How many months experience in a flammable, highly toxic, or toxic refrigerant plant is needed in order to qualify for a 2-C
license?
A. 6 months
B. 3 months
C. 1 month
D. 9 months - ANS -B. 3 months
\If a compound gauge reads 15" Hg, what is the equivalent in psig?
A. -7.5 psig
, B. 30 psig
C. 7.5 psig
D. -15 psig - ANS -C. 7.5 psig
\If there were a sudden drop in temp in the cooling tower of a lithium bromide absorption system, what would happen?
A. crystallization in the system
B. high head pressure in the absorber
C. low pressure in the system
D. low head pressure in the absorber - ANS -A. crystallization in the system
\If you had a compressor operating with a four pole motor at 150hp, 120v, and 60 cycles per sec, what would its RPMs
be?
A. 1800 RPMs
B. 900 RPMs
C. 1600 RPMs
D. 3600 RPMs - ANS -A. 1800 RPMs
RPM = Hz (2/p) 60
\In a refrigeration system using a high-side float, which of the following would control its operation?
A. the evaporator & receiver
B. the accumulator
C. the condenser & receiver
D. the evaporator & condenser - ANS -C. the condenser & receiver
\In a refrigeration system, what effect would an increase in load on the evaporator have on the system?
A. system stays the same
B. suction pressure increases while HP decreases
C. the condenser floods
D. suction pressure increases while HP increases - ANS -B. suction pressure increases while HP decreases
