DC 3rd Class Test Exam Complete
Solution –| Verified Answers.
The component in which liquid vapor by absorbing heat is called?
~CORRECT ANSWER~✓✓evaporator
the best answer for an electrical grounding method? ~CORRECT
ANSWER~✓✓Metal stake drive 8 foot into the ground.
A _____ valve should be used for throttling purposes? ~CORRECT
ANSWER~✓✓Globe
What is the acceptable range for residual sodium sulfite in the boiler
maintain? ~CORRECT ANSWER~✓✓30-70
What is the BTU content of a gallon of #4 fuel oil? ~CORRECT
ANSWER~✓✓146,000
What does a zeolite water softener system use as a means of
regeneration? ~CORRECT ANSWER~✓✓brine
What are the 4 steps for a Zeolite Rejuvenation water softener process?
~CORRECT ANSWER~✓✓Backwash, Brine, Rinse, Service
,Where medium temperature liquid found? ~CORRECT
ANSWER~✓✓Condenser
Where is high temperature vapor found? ~CORRECT ANSWER~✓✓At
the discharge of the compressor or condenser
What stays are used to support the burner chamber in a scotch marine
boiler? ~CORRECT ANSWER~✓✓Diagonal Stays
What type of safety valve is this? ~CORRECT ANSWER~✓✓( Full)
Crosby nozzle-type safety valve. Page 365 BOG
Where do you get superheat reading? ~CORRECT ANSWER~✓✓Take
suction line pressure
Name the wire that connects all component of a system to a physical
ground or water pipe? ~CORRECT ANSWER~✓✓Grounding electrode
conductor
Where do you get sub-cooling reading? ~CORRECT ANSWER~✓✓Take
liquid line pressure
Cross reference to temperature using a P/T Chart
Get liquid line temperature
Subtract actual temperature from cross referenced temperature
,Result is Sub cooling
On the boilers that have both Quick opening and Screw type blow down
valves, the Quick opening valve must be located? ~CORRECT
ANSWER~✓✓closest to the boiler and followed by the screw-type valve
High pressure boilers equipped with Quick opening and Screw type
valves are blown down how? ~CORRECT ANSWER~✓✓By opening the
Quick opening valve first and closing it Last.
ASME Code defines a slow opening valve as what? ~CORRECT
ANSWER~✓✓One requiring at least 5 full 360 degree turns between
full open and close position.
A 300 Horsepower boiler operating at 100psi has an average load of
75% with 80% condensate return and 5% blow down. The treatment
provides a chemical which costs $8.75 per gallon, and will treat 600
gallon. Find the amount of the chemical needed for the day period, and
the cost of the chemical for a 30 days period? ~CORRECT
ANSWER~✓✓Water In = Water Out
Makeup + Condensate Return = Evaporator + Blow Down
Average Evaporator Rate = 300 x 34.5 pph x .75% load = 7762, 50 pph
1 Month + .8( 7762.50 pph) = 7762.50 pph + 0500 m
, 1 Month + 6210 pph = 7762.50 pph + .0500 m
-6210 -6210
1 Month = 1552.5 pph + .0500
.9500 m = 1552.5 pph
.9500m .9500
1Month = 1,634.21 pph
Gallons per Month = 1634..33 x 24 x 30 = 141, 252.24 gallons per
month
Chemical needed = 141,252.24 gallon / 600 gallon = 235, 40 gallon
Cost per month = 235, 40 gallon x 8.75 = $2,059.75
During a 24 hours operation how often should you check the water
level? ~CORRECT ANSWER~✓✓once per shift
How often do you check the high limit switch? ~CORRECT
ANSWER~✓✓Annually
Solution –| Verified Answers.
The component in which liquid vapor by absorbing heat is called?
~CORRECT ANSWER~✓✓evaporator
the best answer for an electrical grounding method? ~CORRECT
ANSWER~✓✓Metal stake drive 8 foot into the ground.
A _____ valve should be used for throttling purposes? ~CORRECT
ANSWER~✓✓Globe
What is the acceptable range for residual sodium sulfite in the boiler
maintain? ~CORRECT ANSWER~✓✓30-70
What is the BTU content of a gallon of #4 fuel oil? ~CORRECT
ANSWER~✓✓146,000
What does a zeolite water softener system use as a means of
regeneration? ~CORRECT ANSWER~✓✓brine
What are the 4 steps for a Zeolite Rejuvenation water softener process?
~CORRECT ANSWER~✓✓Backwash, Brine, Rinse, Service
,Where medium temperature liquid found? ~CORRECT
ANSWER~✓✓Condenser
Where is high temperature vapor found? ~CORRECT ANSWER~✓✓At
the discharge of the compressor or condenser
What stays are used to support the burner chamber in a scotch marine
boiler? ~CORRECT ANSWER~✓✓Diagonal Stays
What type of safety valve is this? ~CORRECT ANSWER~✓✓( Full)
Crosby nozzle-type safety valve. Page 365 BOG
Where do you get superheat reading? ~CORRECT ANSWER~✓✓Take
suction line pressure
Name the wire that connects all component of a system to a physical
ground or water pipe? ~CORRECT ANSWER~✓✓Grounding electrode
conductor
Where do you get sub-cooling reading? ~CORRECT ANSWER~✓✓Take
liquid line pressure
Cross reference to temperature using a P/T Chart
Get liquid line temperature
Subtract actual temperature from cross referenced temperature
,Result is Sub cooling
On the boilers that have both Quick opening and Screw type blow down
valves, the Quick opening valve must be located? ~CORRECT
ANSWER~✓✓closest to the boiler and followed by the screw-type valve
High pressure boilers equipped with Quick opening and Screw type
valves are blown down how? ~CORRECT ANSWER~✓✓By opening the
Quick opening valve first and closing it Last.
ASME Code defines a slow opening valve as what? ~CORRECT
ANSWER~✓✓One requiring at least 5 full 360 degree turns between
full open and close position.
A 300 Horsepower boiler operating at 100psi has an average load of
75% with 80% condensate return and 5% blow down. The treatment
provides a chemical which costs $8.75 per gallon, and will treat 600
gallon. Find the amount of the chemical needed for the day period, and
the cost of the chemical for a 30 days period? ~CORRECT
ANSWER~✓✓Water In = Water Out
Makeup + Condensate Return = Evaporator + Blow Down
Average Evaporator Rate = 300 x 34.5 pph x .75% load = 7762, 50 pph
1 Month + .8( 7762.50 pph) = 7762.50 pph + 0500 m
, 1 Month + 6210 pph = 7762.50 pph + .0500 m
-6210 -6210
1 Month = 1552.5 pph + .0500
.9500 m = 1552.5 pph
.9500m .9500
1Month = 1,634.21 pph
Gallons per Month = 1634..33 x 24 x 30 = 141, 252.24 gallons per
month
Chemical needed = 141,252.24 gallon / 600 gallon = 235, 40 gallon
Cost per month = 235, 40 gallon x 8.75 = $2,059.75
During a 24 hours operation how often should you check the water
level? ~CORRECT ANSWER~✓✓once per shift
How often do you check the high limit switch? ~CORRECT
ANSWER~✓✓Annually
