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DC THIRD TESTING
ACTUAL EXAM WITH CORRECT
SOLUTIONS.
The component in which liquid vapor by absorbing heat is called? - correct answer- Evaporator
Select the best answer electrical grounding method? - correct answer- Metal stake drive 8 foot into the ground.
A _____ valve should be used for throttling purpose? - 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? - correct answer-
146,000
What does a zeolite water softener system use as a means of regeneration? - correct answer- Brine 1 / 4
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What are the 4 steps for a Zeolite Rejuvenation water softener process? - correct answer- Back wash Backwash, brine, rinse, service
Where is medium temperature is 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
What type of safety valve is this? - correct answer- ( Full) Crosby nozzle-type safety valve. Page 365 BOG
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Where do you found superheat reading? - correct answer- 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? - correct answer- Grounding Electrode Conductor
Where do 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
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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. Page 403 BOG
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. 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? - 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
- Month + .8( 7762.50 pph) = 7762.50 pph + 0500 m
- Month + 6210 pph = 7762.50 pph + .0500 m
-6210 -6210
- Month = 1552.5 pph + .0500
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