Electric Boilers Chapter 4

Question 1

1. A main disadvantage of an electric boiler is the:
   A. High cost of manufacturing
   B. High cost of electricity
   C. Inefficiency of the energy transfer
   D. Space requirement per unit output
   E. Requirement for duct work and chimneys

Answer 1

B. High cost of electricity

Question 2

2. Electric boilers:
   A. Require tall stacks for pollution dispersement
   B. Tend not to be very compact
   C. Require soot blowers when the fuel is coal
   D. Have energy conversion efficiencies close to 100%
   E. Add to pollution with the production of ashes and smoke

Answer 2

D. Have energy conversion efficiencies close to 100%

Question 3

3. In an immersion-type electric boiler scale tends to form on the:
A.	Electrodes
B.	Walls of the basket
C.	Watertube bundles
D.	Firetube bundles
E.	Elements

Answer 3

E. Elements

Question 4

4. An advantage of an electric boiler is the:
   A. High cost of manufacturing
   B. High cost of the electricity
   C. Inefficiency of the energy transfer
   D. Compactness of the boiler
   E. Requirement for duct work and chimneys

Answer 4

D. Compactness of the boiler

Question 5

5. Prior to the power being turned on in an electrode type electric boiler the water levels in the two chambers would be:
A.	Higher in the inner chamber
B.	Higher in the outer chamber
C.	The same in both chambers
D.	Lower in the fire tubes
E.	Lower in the water tubes

Answer 5

C. The same in both chambers

Question 6

6. The electrode type electric boiler consists of two cylindrical chambers:
   A. The inner one forming the regulating compartment and the other the generating compartment
   B. The inner one forming the generating compartment and the other the regulating compartment
   C. The inner one forming the regulating compartment and the other the steam compartment
   D. The inner one forming the steam compartment and the other the generating compartment
   E. The inner one forming the fire compartment and the other the generating compartment

Answer 6

B. The inner one forming the ‘‘generating’’ compartment and the other the ‘‘regulating’’ compartment
NOTE: GENERATING AND REGULATING

Question 7

7. The load on an electrode-type electric boiler is maintained by the:
   A. Amount of steam space in the boiler
   B. Amount of electrode covered by water
   C. Outdoor temperature
   D. Amount of current flowing through the elements
   E. The voltage applied to the boiler

Answer 7

B. Amount of electrode covered by water

Question 8

8. Output of an immersion electric boiler is regulated by altering the:
   A. Water level relative to the electrodes
   B. Water level relative to the elements
   C. Amount of current flowing through the water
   D. Amount of current flowing through the elements
   E. The voltage applied to the boiler

Answer 8

D. Amount of current flowing through the elements

Question 9

9.Since pure water will not conduct electricity a predetermined amount of electrolyte (\_\_\_\_\_) is dissolved in the water:
A.	NaOH
B.	H2SO4
C.	NaSO3
D.	HC1
E.	NaC1

Answer 9

E. NaC1

Question 10

10. An immersion-type electric boier has:
A.	Electrodes
B.	No steam space
C.	Elements
D.	Tube bundles
E.	Water tubes

Answer 10

C. Elements

Question 11

11. In the electrode type electric boiler the electrodes are located in the:
A.	Firetube section
B.	Watertube section
C.	Firebox
D.	Windbox
E.	Central generating chamber

Answer 11

E. Central generating chamber

Question 12

Answer: Chapter 4
Electric Boilers

1. B
2. D
3. E
4. D
5. C
6. B
7. B
8. D
9. E
10. C
11. E