DC 3RD CLASS EXAM 2024\2025
DC 3RD CLASS EXAM 2024\2025 WITH GUARANTEED ACCURATE ANSWERS
The component in which liquid vapor by absorbing heat is called? -
Accurate Answers✔✔✔ Evaporator
Select the best answer electrical grounding method? - Accurate
Answers✔✔✔ Metal stake drive 8 foot into the ground.
A _____ valve should be used for throttling purpose? - Accurate
Answers✔✔✔ Globe
What is the acceptable range for residual sodium sulfite in the boiler
maintain? - Accurate Answers✔✔✔ 30-70
,What is the BTU content of a gallon of #4? - Accurate Answers✔✔✔
146,000
What does a zeolite water softener system use as a means of
regeneration? - Accurate Answers✔✔✔ Brine
What are the 4 steps for a Zeolite Rejuvenation water softener process? -
Accurate Answers✔✔✔ Back wash
Backwash, brine, rinse, service
Where is medium temperature is liquid found? - Accurate
Answers✔✔✔ Condenser
Where is high temperature vapor found? - Accurate Answers✔✔✔ At
the discharge of the compressor or condenser
What stays are used to support the burner chamber in a scotch marine
boiler? - Accurate Answers✔✔✔ Diagonal Stays
What type of safety valve is this? - Accurate Answers✔✔✔ ( Full)
Crosby nozzle-type safety valve. Page 365 BOG
What type of safety valve is this? - Accurate Answers✔✔✔ ( Full)
Crosby nozzle-type safety valve. Page 365 BOG
,Where do you found superheat reading? - Accurate Answers✔✔✔ Take
suction line pressure
Cross reference using a P/T Chart
Get tail coil Temperature
Subtract cross references temperature from tail coil temperature
Result will be superheat
Name the wire that connects all component of a system to a physical
ground or water pipe? - Accurate Answers✔✔✔ Grounding Electrode
Conductor
Where do get sub-cooling reading? - Accurate Answers✔✔✔ 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? - Accurate
Answers✔✔✔ 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? - Accurate Answers✔✔✔ By opening the
Quick opening valve first and closing it Last. Page 403 BOG
, ASME Code defines a slow opening valve as what? - Accurate
Answers✔✔✔ One requiring at least 5 full 360 degree turns between
full open and close position. Page 374
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? - Accurate Answers✔✔✔
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
DC 3RD CLASS EXAM 2024\2025 WITH GUARANTEED ACCURATE ANSWERS
The component in which liquid vapor by absorbing heat is called? -
Accurate Answers✔✔✔ Evaporator
Select the best answer electrical grounding method? - Accurate
Answers✔✔✔ Metal stake drive 8 foot into the ground.
A _____ valve should be used for throttling purpose? - Accurate
Answers✔✔✔ Globe
What is the acceptable range for residual sodium sulfite in the boiler
maintain? - Accurate Answers✔✔✔ 30-70
,What is the BTU content of a gallon of #4? - Accurate Answers✔✔✔
146,000
What does a zeolite water softener system use as a means of
regeneration? - Accurate Answers✔✔✔ Brine
What are the 4 steps for a Zeolite Rejuvenation water softener process? -
Accurate Answers✔✔✔ Back wash
Backwash, brine, rinse, service
Where is medium temperature is liquid found? - Accurate
Answers✔✔✔ Condenser
Where is high temperature vapor found? - Accurate Answers✔✔✔ At
the discharge of the compressor or condenser
What stays are used to support the burner chamber in a scotch marine
boiler? - Accurate Answers✔✔✔ Diagonal Stays
What type of safety valve is this? - Accurate Answers✔✔✔ ( Full)
Crosby nozzle-type safety valve. Page 365 BOG
What type of safety valve is this? - Accurate Answers✔✔✔ ( Full)
Crosby nozzle-type safety valve. Page 365 BOG
,Where do you found superheat reading? - Accurate Answers✔✔✔ Take
suction line pressure
Cross reference using a P/T Chart
Get tail coil Temperature
Subtract cross references temperature from tail coil temperature
Result will be superheat
Name the wire that connects all component of a system to a physical
ground or water pipe? - Accurate Answers✔✔✔ Grounding Electrode
Conductor
Where do get sub-cooling reading? - Accurate Answers✔✔✔ 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? - Accurate
Answers✔✔✔ 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? - Accurate Answers✔✔✔ By opening the
Quick opening valve first and closing it Last. Page 403 BOG
, ASME Code defines a slow opening valve as what? - Accurate
Answers✔✔✔ One requiring at least 5 full 360 degree turns between
full open and close position. Page 374
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? - Accurate Answers✔✔✔
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
