1st Class Stationary Engineer's Examination #4
70 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (VERIFIED
ANSWERS) ALREADY GRADED A+ 2025 NEW
UPDATE
________ Is used to protect the compressor of a refrigeration system from slugs of
liquid refrigerant. - CORRECT ANSWER: False head
A ___________ pump requires no air chamber on the discharge line. - CORRECT
ANSWER: centrifugal
A hydrostatic test of a boiler should be conducted at a test pressure of - CORRECT
ANSWER: 1 - 1/2 times the safe working pressure
a Kilowatt is equal to how many horsepower? - CORRECT ANSWER: 1000 watts / 746
Watts per hp = 1.34 hp
A pump will not handle hot water from below the pump level, but.... - CORRECT
ANSWER: it will pump hot water supplied from above it
A short piece of pipe, the thread external on both ends is a - CORRECT ANSWER:
Nipple
Absolute zero is - CORRECT ANSWER: -460 F
Air being compressed by a two-stage aircompressor can be cooled by the use of a -
CORRECT ANSWER: intercooler
, An electric boiler generates 34.5 lbs. of steam per hour for every 10 kilowatt hour. True
or False - CORRECT ANSWER: True
An electrical motor draws 50 amperes at 220 volts. What horsepower is delivered at the
pulley of the motor if the efficiency is 90% - CORRECT ANSWER: 11,000 watts / 746
watts per hp = 14.74hp
14.74 hp x 90% = 13.27
Atomization of fuel oil in a horizontal rotary cup oil burner is primarily due to -
CORRECT ANSWER: The rotating cup and primary air
Controls pump output volume - CORRECT ANSWER: Discharge valves
Direction of the pump movement - CORRECT ANSWER: Rotation
Dry boiler storage is better than - CORRECT ANSWER: wet boiler storage
firetubes are fastened to the tube sheet by - CORRECT ANSWER: expanding or rolling
Hard scale in a boiler is produced by - CORRECT ANSWER: Calcium sulfate
Hartford loops are only used on boilers with a - CORRECT ANSWER: Gravity return
system
How does a motor differ from a generator - CORRECT ANSWER: a motor receives
electrical energy and turns it into mechanical energy and a generator receives
mechanical energy and turns it into electrical energy.
70 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (VERIFIED
ANSWERS) ALREADY GRADED A+ 2025 NEW
UPDATE
________ Is used to protect the compressor of a refrigeration system from slugs of
liquid refrigerant. - CORRECT ANSWER: False head
A ___________ pump requires no air chamber on the discharge line. - CORRECT
ANSWER: centrifugal
A hydrostatic test of a boiler should be conducted at a test pressure of - CORRECT
ANSWER: 1 - 1/2 times the safe working pressure
a Kilowatt is equal to how many horsepower? - CORRECT ANSWER: 1000 watts / 746
Watts per hp = 1.34 hp
A pump will not handle hot water from below the pump level, but.... - CORRECT
ANSWER: it will pump hot water supplied from above it
A short piece of pipe, the thread external on both ends is a - CORRECT ANSWER:
Nipple
Absolute zero is - CORRECT ANSWER: -460 F
Air being compressed by a two-stage aircompressor can be cooled by the use of a -
CORRECT ANSWER: intercooler
, An electric boiler generates 34.5 lbs. of steam per hour for every 10 kilowatt hour. True
or False - CORRECT ANSWER: True
An electrical motor draws 50 amperes at 220 volts. What horsepower is delivered at the
pulley of the motor if the efficiency is 90% - CORRECT ANSWER: 11,000 watts / 746
watts per hp = 14.74hp
14.74 hp x 90% = 13.27
Atomization of fuel oil in a horizontal rotary cup oil burner is primarily due to -
CORRECT ANSWER: The rotating cup and primary air
Controls pump output volume - CORRECT ANSWER: Discharge valves
Direction of the pump movement - CORRECT ANSWER: Rotation
Dry boiler storage is better than - CORRECT ANSWER: wet boiler storage
firetubes are fastened to the tube sheet by - CORRECT ANSWER: expanding or rolling
Hard scale in a boiler is produced by - CORRECT ANSWER: Calcium sulfate
Hartford loops are only used on boilers with a - CORRECT ANSWER: Gravity return
system
How does a motor differ from a generator - CORRECT ANSWER: a motor receives
electrical energy and turns it into mechanical energy and a generator receives
mechanical energy and turns it into electrical energy.
