Podcast
Questions and Answers
The component in which liquid vapor by absorbing heat is called?
The component in which liquid vapor by absorbing heat is called?
evaporator
What is the best answer for an electrical grounding method?
What is the best answer for an electrical grounding method?
Metal stake driven 8 feet into the ground.
A _____ valve should be used for throttling purposes?
A _____ valve should be used for throttling purposes?
Globe
What is the acceptable range for residual sodium sulfite in the boiler maintain?
What is the acceptable range for residual sodium sulfite in the boiler maintain?
What is the BTU content of a gallon of #4 fuel oil?
What is the BTU content of a gallon of #4 fuel oil?
What does a zeolite water softener system use as a means of regeneration?
What does a zeolite water softener system use as a means of regeneration?
What are the 4 steps for a Zeolite Rejuvenation water softener process?
What are the 4 steps for a Zeolite Rejuvenation water softener process?
Where is medium temperature liquid found?
Where is medium temperature liquid found?
Where is high temperature vapor found?
Where is high temperature vapor found?
What stays are used to support the burner chamber in a scotch marine boiler?
What stays are used to support the burner chamber in a scotch marine boiler?
What type of safety valve is this?
What type of safety valve is this?
Where do you get a superheat reading?
Where do you get a superheat reading?
Name the wire that connects all components of a system to a physical ground or water pipe?
Name the wire that connects all components of a system to a physical ground or water pipe?
Where do you get sub-cooling reading?
Where do you get sub-cooling reading?
On the boilers that have both quick opening and screw type blow down valves, where must the Quick opening valve be located?
On the boilers that have both quick opening and screw type blow down valves, where must the Quick opening valve be located?
High pressure boilers equipped with quick opening and screw type valves are blown down how?
High pressure boilers equipped with quick opening and screw type valves are blown down how?
ASME Code defines a slow opening valve as what?
ASME Code defines a slow opening valve as what?
A 300 Horsepower boiler operating at 100 psi has a load of 75% with 80% condensate return and 5% blow down. Find the amount of chemical needed for the day period.
A 300 Horsepower boiler operating at 100 psi has a load of 75% with 80% condensate return and 5% blow down. Find the amount of chemical needed for the day period.
During a 24 hours operation how often should you check the water level?
During a 24 hours operation how often should you check the water level?
How often do you check the high limit switch?
How often do you check the high limit switch?
What is the recommended time for a complete external inspection of a boiler?
What is the recommended time for a complete external inspection of a boiler?
What is the first thing to do when shutting down a boiler?
What is the first thing to do when shutting down a boiler?
A flow control should be blown down when?
A flow control should be blown down when?
How often should you check the Low Water Fuel Cut off?
How often should you check the Low Water Fuel Cut off?
Why is oil added to the refrigerant?
Why is oil added to the refrigerant?
Recycled and filtered refrigerant can be used where?
Recycled and filtered refrigerant can be used where?
Data printed on the equipment nameplate would include manufacturer, model, and serial number and _________________?
Data printed on the equipment nameplate would include manufacturer, model, and serial number and _________________?
How many BTUs does it take to raise 10 lbs of steam from 40 to 41 degrees?
How many BTUs does it take to raise 10 lbs of steam from 40 to 41 degrees?
When working on a boiler, permits should be required?
When working on a boiler, permits should be required?
How many things do safety controls protect against?
How many things do safety controls protect against?
What chemical compounds in water cause permanent hardness?
What chemical compounds in water cause permanent hardness?
What chemicals are used to combat corrosion?
What chemicals are used to combat corrosion?
You have boiler water that is found to have a pH of 5. What compound do you add to neutralize?
You have boiler water that is found to have a pH of 5. What compound do you add to neutralize?
What produces soft scale?
What produces soft scale?
With normal oxygen and low alkalinity, what is added to boiler water?
With normal oxygen and low alkalinity, what is added to boiler water?
What is hard forming scale?
What is hard forming scale?
Which chemicals are used to combat scale?
Which chemicals are used to combat scale?
Which compound is not heat produce?
Which compound is not heat produce?
What takes no actual action in combustion?
What takes no actual action in combustion?
With hydroxide present & normal oxygen levels, which chemical will cause problems?
With hydroxide present & normal oxygen levels, which chemical will cause problems?
What mechanical device is used to remove scale from fire tubes?
What mechanical device is used to remove scale from fire tubes?
Who can make adjustments or repairs on a safety valve?
Who can make adjustments or repairs on a safety valve?
What mechanical device is used to remove scale from water tubes?
What mechanical device is used to remove scale from water tubes?
In a duct air handling system, how does a space thermostat control building temperatures?
In a duct air handling system, how does a space thermostat control building temperatures?
The removal of moisture from air using a cooling coil is called _________ dehumidification?
The removal of moisture from air using a cooling coil is called _________ dehumidification?
In a multi-zone air handler unit, how does the zone thermostat control the zone temperature?
In a multi-zone air handler unit, how does the zone thermostat control the zone temperature?
An air handler unit that has hot & cold air ducts connected to __________ is called a __________ air handler unit?
An air handler unit that has hot & cold air ducts connected to __________ is called a __________ air handler unit?
An air handler unit supplies a constant supply air temperature of 55 degree F to building spaces and includes a coil called _____ air handler unit?
An air handler unit supplies a constant supply air temperature of 55 degree F to building spaces and includes a coil called _____ air handler unit?
An air handler unit that provides heating, cooling, ventilation, and air conditioning to more than one building or area and has its cooling & heating Coil in separate side-by-side ducts is called a _______ air handling unit?
An air handler unit that provides heating, cooling, ventilation, and air conditioning to more than one building or area and has its cooling & heating Coil in separate side-by-side ducts is called a _______ air handling unit?
In a dual duct air handling system space thermostatic controls building temperatures by? Moving the air from the hot & cold duct in a molding box serving the space.
In a dual duct air handling system space thermostatic controls building temperatures by? Moving the air from the hot & cold duct in a molding box serving the space.
A boiler is rated at (86,250 lbs, 88,250 lbs, 96,250 lbs) of steam per hour. What is the equivalent boiler horsepower?
A boiler is rated at (86,250 lbs, 88,250 lbs, 96,250 lbs) of steam per hour. What is the equivalent boiler horsepower?
What is the area of a steam engine cylinder reading 10 x 24, when the piston is only travelling at 2/3 of the way?
What is the area of a steam engine cylinder reading 10 x 24, when the piston is only travelling at 2/3 of the way?
What is the total force acting on a 4 inches diameter safety value disc with a boiler pressure of 12 psi?
What is the total force acting on a 4 inches diameter safety value disc with a boiler pressure of 12 psi?
The expansion tank on a closed loop system should be located?
The expansion tank on a closed loop system should be located?
What is the primary purpose of a crank case heater on a reciprocating chiller?
What is the primary purpose of a crank case heater on a reciprocating chiller?
What is meant by the percent of (skip, step, and slip) in a pump?
What is meant by the percent of (skip, step, and slip) in a pump?
Which of the following type of pumps can be started with the discharge valve closed?
Which of the following type of pumps can be started with the discharge valve closed?
The vertical distance from the center line of the pump up to the top level of the supply tank is called?
The vertical distance from the center line of the pump up to the top level of the supply tank is called?
Where in a system is a foot valve value installed and what is its purpose?
Where in a system is a foot valve value installed and what is its purpose?
In a multi-zone air handling unit, how does the zone thermostat control the zone temperature?
In a multi-zone air handling unit, how does the zone thermostat control the zone temperature?
What is meant by a pump becoming steam bound?
What is meant by a pump becoming steam bound?
Which of the following is a positive displacement pump?
Which of the following is a positive displacement pump?
What does the whistle on the top of the water column indicating?
What does the whistle on the top of the water column indicating?
The heart of a refrigeration system is the _______?
The heart of a refrigeration system is the _______?
Refrigerant flow into the evaporator is controlled by ___________?
Refrigerant flow into the evaporator is controlled by ___________?
A reciprocating compressor operating with refrigerant R-410 head pressure of 476 psi and a suction pressure of 118 psi. What is the compressor's compression ratio?
A reciprocating compressor operating with refrigerant R-410 head pressure of 476 psi and a suction pressure of 118 psi. What is the compressor's compression ratio?
The part of the refrigeration system that absorbs heat into the system is controlled by the ______?
The part of the refrigeration system that absorbs heat into the system is controlled by the ______?
What is the replacement refrigerant for R-12 medium and high temperature refrigeration application?
What is the replacement refrigerant for R-12 medium and high temperature refrigeration application?
The color for an R-134A refrigerant cylinder is _______?
The color for an R-134A refrigerant cylinder is _______?
The color for an R-410A refrigerant cylinder is _______?
The color for an R-410A refrigerant cylinder is _______?
Which of the following is a flanged joint between two or more furnaces and may be located in the center of the furnace, with no more than 18 inches apart?
Which of the following is a flanged joint between two or more furnaces and may be located in the center of the furnace, with no more than 18 inches apart?
Which of the following statements is true concerning fire tube and water tube boilers?
Which of the following statements is true concerning fire tube and water tube boilers?
A chief engineer is preparing for a mud drum inspection. Which of the following will you not do?
A chief engineer is preparing for a mud drum inspection. Which of the following will you not do?
What do you use to bank off a boiler and bring it back online without using the shut-off valve?
What do you use to bank off a boiler and bring it back online without using the shut-off valve?
What is not an advantage of an economic boiler over a conventional HRT Boiler?
What is not an advantage of an economic boiler over a conventional HRT Boiler?
What do you call the chemicals that are used to test water for hardness?
What do you call the chemicals that are used to test water for hardness?
What do the three 'T's of combustion stand for?
What do the three 'T's of combustion stand for?
What do you do to attain complete combustion in a boiler?
What do you do to attain complete combustion in a boiler?
Air leaking into the inner and outer parts of the boiler, what will happen?
Air leaking into the inner and outer parts of the boiler, what will happen?
By clicking on the exhibit, the picture is a display of (page 365 BOG)?
By clicking on the exhibit, the picture is a display of (page 365 BOG)?
What controls the steam pressure and monitors the combustion air intake?
What controls the steam pressure and monitors the combustion air intake?
What happens to the water in a boiler that is at 80% load and all of a sudden, the flame goes off?
What happens to the water in a boiler that is at 80% load and all of a sudden, the flame goes off?
What is installed between the boiler drum and the steam gauge to create a protective watertight seal for the gauge?
What is installed between the boiler drum and the steam gauge to create a protective watertight seal for the gauge?
What is the replacement refrigerant for R-22?
What is the replacement refrigerant for R-22?
Which valves to the boiler are opened and closed during blow down?
Which valves to the boiler are opened and closed during blow down?
How and why tube ends on a fire tube boiler are secure?
How and why tube ends on a fire tube boiler are secure?
What is not an advantage of the economic type boiler over the conventional type boiler?
What is not an advantage of the economic type boiler over the conventional type boiler?
An accelerated circulation water tube is characterized by?
An accelerated circulation water tube is characterized by?
Why is platinum used in RTD (Resistive Temperature Device)?
Why is platinum used in RTD (Resistive Temperature Device)?
In HVAC systems controlled by a thermostat, what is the difference?
In HVAC systems controlled by a thermostat, what is the difference?
What is the purpose of a suction accumulator?
What is the purpose of a suction accumulator?
What must be submitted to the code official when field assembly of boilers is required?
What must be submitted to the code official when field assembly of boilers is required?
A boiler has 2800 furnace temperature and 600 stack temperatures reading. What is the boiler efficiency?
A boiler has 2800 furnace temperature and 600 stack temperatures reading. What is the boiler efficiency?
What do you call a reading from the center of an impeller across to the gauge?
What do you call a reading from the center of an impeller across to the gauge?
What is the heart of a refrigeration system?
What is the heart of a refrigeration system?
Which coal has the biggest level of fixed carbon content?
Which coal has the biggest level of fixed carbon content?
What is the cause of high excess in a condensate return tank with temperature up to 20 degrees above normal?
What is the cause of high excess in a condensate return tank with temperature up to 20 degrees above normal?
Water inlet into a building is 100 psig. If no booster pumps are used, what will be the pressure on the 10th floor, if the building is 10 feet per floor?
Water inlet into a building is 100 psig. If no booster pumps are used, what will be the pressure on the 10th floor, if the building is 10 feet per floor?
Where is the total hardness of a softener reading 0.5 grains?
Where is the total hardness of a softener reading 0.5 grains?
How many BTUs are needed to raise 2 lbs of water from 32 °F to 212 °F?
How many BTUs are needed to raise 2 lbs of water from 32 °F to 212 °F?
Study Notes
Heating and Cooling Systems
- An evaporator absorbs heat to convert liquid into vapor.
- Grounding methods utilize an 8-foot metal stake driven into the ground for electrical safety.
- Globe valves are ideal for throttling applications.
- Medium temperature liquid is typically found in a condenser, while high temperature vapor is at the discharge of a compressor or condenser.
- The centrifugal pump can start with a closed discharge valve, while reciprocating pumps are positive displacement types.
Boiler Operations and Maintenance
- Acceptable residual sodium sulfite range in boilers is between 30-70 ppm.
- BTU content of a gallon of #4 fuel oil is 146,000 BTUs.
- Blowdown procedures for boilers involve opening quick opening valves first and closing them last.
- Chemical needs for boiler treatment can be calculated based on evaporator rates and condensate return.
- A thorough external boiler inspection is recommended once per shift, along with checking water levels and safety controls.
Water Chemistry in Boilers
- Permanent hardness in water is caused by compounds like calcium sulfate and magnesium silicate.
- Corrosion in boilers can be combated by chemicals such as sodium sulfite and hydrazine.
- Soft scale is formed from calcium carbonate and magnesium carbonate, while hard scale is primarily silica.
- A neutralizing agent should be added to raise the pH of acidic boiler water.
Refrigeration and Air Handling Systems
- Refrigerant migrations are prevented by using crankcase heaters and oil mixed with refrigerants for lubrication.
- In refrigeration systems, the compressor is the critical component, while metering devices control refrigerant flow into evaporators.
- R-134A is a replacement refrigerant for R-12, marked with light blue cylinders, while R-410A is identified by rose-colored cylinders.
- Air handling units that provide heating, cooling, and ventilation are categorized by configurations like multi-zone and dual duct systems.
Pressure and Flow Dynamics
- The specific gravity of fluids can be defined in terms of pressure, such as calculating pressure loss over height in buildings (2.31 feet = 1 psi).
- A sighon installation between boiler drums and steam gauges creates a protective seal to prevent steam escape.
- Superheating and subcooling realities in refrigerants are measured by comparing suction and liquid line temperatures to their respective pressure/temperature charts.
Safety Protocols and Regulations
- Safety valves must only be adjusted by qualified personnel.
- Annual maintenance includes checking high limit switches, while low water fuel cut-off checks should occur per shift.
- Boiler operation permits are required for each shift to ensure compliance with safety standards and regulations.
Energy Consumption and Efficiency
- Boiler efficiency ratings can be calculated — for instance, a boiler with an input of 2800°F and a stack temperature of 600°F reflects an efficiency of 78.57%.
- Understanding and applying the combustion principles, represented as the three “T”s (Time, Temperature, Turbulence), is critical for optimal efficiency.
- Energy calculations for steam generation can quantify required BTUs for temperature changes in varying quantities of water.
Additional Terminology
- "Reagents" are used in testing water hardness, while "diagonal stays" support burner chambers in boilers.
- The difference between actual and theoretical pump capacity is referred to as skip, step, or slip percentages.
- Water's thermal expansion and behavior under varying temperatures are crucial for maintaining system integrity and efficiency.
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Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz consists of flashcards designed to help you prepare for the 3rd Class DC exam. Each card presents a question related to electrical and boiler systems, focusing on fundamental concepts such as evaporators, grounding methods, and valve types. Test your knowledge and reinforce your understanding of critical topics in this field.
