# Boiler Operator 3rd-test 3-4 Blue Book

Approved & Edited by ProProfs Editorial Team
The editorial team at ProProfs Quizzes consists of a select group of subject experts, trivia writers, and quiz masters who have authored over 10,000 quizzes taken by more than 100 million users. This team includes our in-house seasoned quiz moderators and subject matter experts. Our editorial experts, spread across the world, are rigorously trained using our comprehensive guidelines to ensure that you receive the highest quality quizzes.
Learn about Our Editorial Process
| By Mikdenluv
M
Mikdenluv
Community Contributor
Quizzes Created: 2 | Total Attempts: 9,232
Questions: 25 | Attempts: 2,408

Settings

Boiler operators are responsible for maintaining heating systems in large buildings in the boiler, engine, and mechanical rooms. The Boiler Operator 3rd-test below covers 3-4 blue book is designed to help you understand your class work more and prepare you for the upcoming exam. Give it a shot!

• 1.

### A flame rod ____.

• A.

Regulates steam flow

• B.

Ignites the fuel oil

• C.

Ensures that the gas pilot is lighted

• D.

Measures heat in the boiler

C. Ensures that the gas pilot is lighted
Explanation
A flame rod ensures that the gas pilot is lighted by detecting the presence of a flame. It is a safety device that is used in gas-fired appliances such as boilers. When the gas pilot is ignited, the flame rod senses the flame and sends a signal to the control system to confirm that the pilot is lit. If the flame rod does not detect a flame, it will shut off the gas supply to prevent the buildup of unburned gas. This ensures the safe and efficient operation of the appliance.

Rate this question:

• 2.

### There are approximately ____ Btu in 1 cu ft of natural gas.

• A.

100

• B.

1000

• C.

3000

• D.

5000

B. 1000
Explanation
The correct answer is 1000 because a British thermal unit (Btu) is a unit of energy. It is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. Natural gas is typically measured in cubic feet (cu ft), and it has an energy content of approximately 1000 Btu per cubic foot. Therefore, there are approximately 1000 Btu in 1 cu ft of natural gas.

Rate this question:

• 3.

### The ph of boiler water may be controlled by using ____.

• A.

Sulphite

• B.

Sulphate

• C.

Caustic soda

• D.

Softened feedwater

C. Caustic soda
Explanation
Caustic soda can be used to control the pH of boiler water. Caustic soda, also known as sodium hydroxide, is a strong base that can neutralize acidic components in the water, thereby adjusting the pH to the desired level. It helps prevent corrosion and scale formation in the boiler system by maintaining the water's alkalinity. By adding caustic soda to the boiler water, the pH can be controlled within the recommended range for efficient and safe operation of the boiler.

Rate this question:

• 4.

### Boiler water with a ph of 11 is ____.

• A.

Alkaline

• B.

Acidic

• C.

Neutral

• D.

Hard

A. Alkaline
Explanation
Boiler water with a pH of 11 is alkaline. pH is a measure of the acidity or alkalinity of a solution, with values below 7 indicating acidity, values above 7 indicating alkalinity, and a pH of 7 indicating neutrality. Since the pH of the boiler water is 11, it is above 7, making it alkaline.

Rate this question:

• 5.

### A scotch marine boiler is easily identified because it ____.

• A.

Has a brick setting

• B.

Has a cylindrical internal furnace

• C.

Is externally fired

• D.

Has waterwalls

B. Has a cylindrical internal furnace
Explanation
A scotch marine boiler is easily identified because it has a cylindrical internal furnace. This means that the furnace is in the shape of a cylinder, which is a distinguishing feature of this type of boiler. Other types of boilers may have different furnace designs, such as rectangular or square shapes. Therefore, the presence of a cylindrical internal furnace is a key characteristic that helps identify a scotch marine boiler.

Rate this question:

• 6.

### The air flow switch at the burner fan housing ____.

• A.

Ensures the primary air fan is functioning

• B.

Controls the secondary air damper

• C.

Controls the boiler operating range

• D.

Controls the boiler water temperature

A. Ensures the primary air fan is functioning
Explanation
The air flow switch at the burner fan housing ensures the primary air fan is functioning. This switch is designed to detect the presence or absence of air flow in the burner fan housing. If there is no air flow, it indicates a malfunction in the primary air fan. By detecting this, the switch ensures that the primary air fan is functioning properly, which is crucial for the overall operation of the system.

Rate this question:

• 7.

### The ASME code recommends that low water fuel cutoffs be tested by an evaporation test ____.

• A.

Daily

• B.

Weekly

• C.

Monthly

• D.

Yearly

C. Monthly
Explanation
The ASME code recommends that low water fuel cutoffs be tested by an evaporation test monthly. This means that the test should be conducted once every month. By conducting the test regularly, any potential issues with the low water fuel cutoffs can be identified and addressed in a timely manner, ensuring the safety and efficiency of the system. Regular testing also helps to prevent any potential accidents or malfunctions that may occur due to low water levels in the fuel cutoffs.

Rate this question:

• 8.

### A neutral solution is ____ on the ph scale.

• A.

0

• B.

3.5

• C.

7

• D.

14

C. 7
Explanation
A neutral solution is represented by a pH value of 7 on the pH scale. The pH scale measures the acidity or alkalinity of a solution, with values below 7 indicating acidity, values above 7 indicating alkalinity, and a value of 7 indicating neutrality. Therefore, a pH value of 7 signifies that the solution is neither acidic nor alkaline, but rather neutral.

Rate this question:

• 9.

### A dry pipe separator ____.

• A.

Delivers higher quality steam to the header

• B.

Distributes feedwater the length of the drum

• C.

Prevents water hammer

• D.

Agitates the water in the steam and water drum

A. Delivers higher quality steam to the header
Explanation
A dry pipe separator delivers higher quality steam to the header by separating the water droplets from the steam. It ensures that only dry steam enters the header, which improves the overall efficiency of the system. By removing the water droplets, the dry pipe separator prevents any potential water hammer issues and ensures that the steam delivered to the header is of the highest quality.

Rate this question:

• 10.

### Draft is carefully controlled to ____.

• A.

Maintain at least 15% CO in gases of combustion

• B.

Completely burn fuel supplied to the burner

• C.

Prevent the boiler from overheating

• D.

Maintain high levels of excess air in gases of combustion

B. Completely burn fuel supplied to the burner
Explanation
The correct answer is "completely burn fuel supplied to the burner." This means that the draft is carefully controlled to ensure that all the fuel supplied to the burner is burned completely. This is important because incomplete combustion can result in the release of harmful pollutants into the environment and can also lead to lower efficiency in the combustion process. By carefully controlling the draft, the system can optimize the combustion process and ensure that the fuel is burned efficiently and completely.

Rate this question:

• 11.

### Draft is measured with a ____.

• A.

Pyrometer

• B.

Hydrometer

• C.

Manometer

• D.

Potentiometer

C. Manometer
Explanation
A manometer is a device used to measure the pressure of a fluid, such as a gas or liquid. It consists of a U-shaped tube filled with a liquid, typically mercury or water, and the pressure of the fluid being measured causes a difference in the levels of the liquid in the two arms of the tube. This difference in liquid level can be used to determine the pressure of the fluid. Therefore, a manometer is the appropriate instrument for measuring pressure, making it the correct answer for this question.

Rate this question:

• 12.

### A ringleman test is used to determine ____.

• A.

CO2 in gases of combustion

• B.

Smoke density

• C.

Flame failure

• D.

Steam quality

B. Smoke density
Explanation
A ringleman test is used to determine smoke density. This test involves comparing the density of smoke produced by a combustion process to a standard scale called the Ringelmann chart. The test helps in assessing the opacity of smoke and determining the level of air pollution caused by the combustion process. By measuring smoke density, the test can provide valuable information about the efficiency of combustion, the presence of pollutants, and the overall environmental impact.

Rate this question:

• 13.

### A flame scanner proves (verifies) ____.

• A.

Beta rays

• B.

Heat

• C.

Pilot and main flame

• D.

X rays

C. Pilot and main flame
Explanation
A flame scanner is a device used to detect and monitor the presence and quality of a flame in industrial processes. It is commonly used in applications such as boilers, furnaces, and burners. The flame scanner works by detecting the UV radiation emitted by the flame. By verifying the pilot and main flame, the flame scanner ensures that the flame is present and stable, preventing any potential hazards or malfunctions in the system.

Rate this question:

• 14.

### According to the ASME code, when warming up a boiler the air cock is closed when ____.

• A.

Steam starts to come out of the boiler

• B.

The steam pressure gauge reads 25 psi

• C.

The steam pressure gauge reads 35 psi

• D.

The boiler goes on-line

B. The steam pressure gauge reads 25 psi
Explanation
According to the ASME code, the air cock is closed when the steam pressure gauge reads 25 psi. This indicates that the boiler has reached a sufficient pressure level for operation and that the air cock can be closed to prevent any further release of air from the system.

Rate this question:

• 15.

### A motor rated at 25 HP delivering 20 HP  is operating at ____ % capacity.

• A.

75

• B.

80

• C.

85

• D.

90

B. 80
Explanation
The motor is rated at 25 HP but is only delivering 20 HP. To find the percentage capacity, we divide the delivered power by the rated power and multiply by 100. In this case, (20/25) * 100 = 80%. Therefore, the motor is operating at 80% capacity.

Rate this question:

• 16.

### A deposit of scale or mud in an HRT boiler could cause ____.

• A.

A bag to develop

• B.

A draft loss

• C.

Overheating of the breeching

• D.

Lowering of the chimney temperature

A. A bag to develop
Explanation
A deposit of scale or mud in an HRT boiler could cause a bag to develop. This is because the scale or mud can block or restrict the flow of water or steam in the boiler, leading to a buildup of pressure. This increased pressure can cause the boiler to rupture or burst, resulting in the development of a bag.

Rate this question:

• 17.

### Waterwall tubes protect the refractory and ____.

• A.

Increase boiler heating surface

• B.

Act as stays for tube sheets

• C.

Allow the operator to blow down while steaming

• D.

Help control water circulation

A. Increase boiler heating surface
Explanation
Waterwall tubes are an integral part of a boiler's design and serve multiple purposes. One of their functions is to increase the heating surface area of the boiler. By extending the surface area through the waterwall tubes, more heat can be transferred to the water, resulting in increased efficiency and overall heating capacity. This allows for better heat transfer and improved steam production within the boiler system.

Rate this question:

• 18.

### Steam at 250 psia and 400*F is considered ____.

• A.

Supersaturated

• B.

Saturated

• C.

Superheated

• D.

Steam temperature cannot exceed 212*F

B. Saturated
Explanation
Steam at 250 psia and 400°F is considered saturated because it exists in a state where it contains both vapor and liquid phases in equilibrium. At this condition, the steam has reached its maximum temperature and pressure without changing phase.

Rate this question:

• 19.

### Sensible heat is heat that ____.

• A.

Changes a substance's state but not its temperature

• B.

Changes a substances's temperature and its state

• C.

Changes a substance's temperature but not its state

• D.

Is 970.3 Btu/lb of steam

C. Changes a substance's temperature but not its state
Explanation
Sensible heat refers to the heat transfer that causes a change in temperature of a substance without changing its state. This means that the heat energy is absorbed or released by the substance, resulting in an increase or decrease in temperature, but the substance remains in the same physical state (solid, liquid, or gas). Sensible heat does not cause any phase changes such as melting, boiling, or condensation.

Rate this question:

• 20.

### Extra heavy pipe must be used on blowdown lines when the steam pressure exceeds ____ psi.

• A.

15

• B.

100

• C.

125

• D.

200

C. 125
Explanation
When the steam pressure exceeds 125 psi, it is necessary to use an extra heavy pipe on blowdown lines. This is because the higher steam pressure creates a greater force and stress on the pipe, which requires a stronger and more durable pipe to withstand the pressure. Using a regular or lighter pipe could result in pipe failure or leaks, which can be dangerous and cause damage to the system. Thus, an extra heavy pipe is necessary to ensure the safety and integrity of the blowdown lines.

Rate this question:

• 21.

### To check the water level on a boiler on-line, it is best to ____.

• A.

Give the boiler a bottom blowdown

• B.

Blow down the gauge glass

• C.

Lower the steam pressure

• D.

Check the log sheet

B. Blow down the gauge glass
Explanation
To check the water level on a boiler online, it is best to blow down the gauge glass. This is because the gauge glass is specifically designed to show the water level in the boiler. By blowing down the gauge glass, any impurities or debris that may be obstructing the view of the water level can be cleared, ensuring an accurate reading. This method allows for real-time monitoring of the water level, which is crucial for maintaining the safety and efficiency of the boiler.

Rate this question:

• 22.

### A steam pressure gauge has a siphon between the boiler and the pressure gauge to ____.

• A.

Allow for expansion and contraction

• B.

Prevent water from entering the pressure gauge

• C.

Protect the pressure gauge from high steam pressure

• D.

Prevent steam from entering the pressure gauge

D. Prevent steam from entering the pressure gauge
Explanation
The siphon in a steam pressure gauge is used to prevent steam from entering the pressure gauge. Steam can cause damage to the internal components of the gauge and affect its accuracy. The siphon acts as a barrier, allowing only condensed water to enter the gauge while preventing steam from reaching it. This ensures that the pressure reading is accurate and protects the gauge from potential damage.

Rate this question:

• 23.

### If a boilere evaporates 50,000 lb of steam/hr and is evaporating 10 lb of steam/sq ft of heating surface, the heating surface of the boiler is ____ sq ft.

• A.

50

• B.

500

• C.

5,000

• D.

50,000

C. 5,000
Explanation
The question provides two pieces of information: the rate at which steam is evaporated (50,000 lb/hr) and the rate at which steam is evaporated per square foot of heating surface (10 lb/sq ft). To find the heating surface of the boiler, we can divide the total steam evaporated by the rate of evaporation per square foot. Therefore, 50,000 lb/hr divided by 10 lb/sq ft equals 5,000 sq ft.

Rate this question:

• 24.

### Oxygen in feedwater causes ____.

• A.

Priming

• B.

Foaming

• C.

Pitting

• D.

Scale

C. Pitting
Explanation
Oxygen in feedwater causes pitting. Pitting refers to the localized corrosion of metal surfaces, resulting in the formation of small holes or pits. Oxygen can react with the metal surface, leading to the formation of metal oxides and weakening the material. This can result in the formation of pits on the surface, which can eventually lead to structural damage or failure.

Rate this question:

• 25.

### It is permissible to have one blowdown valve on a boiler operated under ____ psi.

• A.

100

• B.

125

• C.

150

• D.

200

A. 100
Explanation
The correct answer is 100 because blowdown valves are used to remove impurities and sediment from the boiler water. They are typically operated at a pressure of 100 psi or lower to prevent damage to the valve and ensure safe operation of the boiler.

Rate this question:

Quiz Review Timeline +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

• Current Version
• Mar 20, 2023
Quiz Edited by
ProProfs Editorial Team
• Dec 29, 2009
Quiz Created by
Mikdenluv

Related Topics