Book 1: Unit 2 - Review

Question 1

The infrared scanner is mounted on the end of a sighting tube in such a way that it’s temperature will not exceed:
Select one:

A. 150°C (302°F)
B. 75°C (167°F)
C. 120°C (248°F)
D. 100°C (212°F)
E. 50°C (98°F)

Answer 1

E. 50°C

Question 2

This scanner is mounted as close to the flame as physically possible without subjecting it to a temperature over:
Select one:

A. 50°C (98°F)
B. 150°C (302°F)
C. 100°C (212°F)
D. 75°C (167°F)
E. 120°C (248°F)

Answer 2

C. 100°C (212°F)

Question 3

Damper position switches are found on boilers with the following burner control system:
1. On-Off control
2. High-low control
3. Modulating control
4. High Limit control

Select one:
A. 1,3
B. 1,2
C. 2,3
D. 4,5
E. 3,4

Answer 3

C. 2,3

Question 4

Quick closing gauge glass valves require _______ turn/s to close.

Select one:
A. 1
B. 1/2
C. 1/4
D. 3
E. 2

Answer 4

C. 1/4

Question 5

The lock-out switch will be actuated when the:
Select one:
A. Power fails
B. Low water fuel cut off opens
C. Flame scanner loses the flame
D. Operating control opens
E. Operating control closed

Answer 5

C. Flame scanner losses the flame

Question 6

The low gas pressure cut-off switch can be tested by:
Select one:
A. Closing the main gas valve quickly
B. Slowly raising the boiler pressure above the operating setpoint
C. Quickly closing the main burner shut-off valve
D. Slowly covering the air supply to the fan
E. Slowly closing the main gas valve

Answer 6

E. Slowly closing the main gas valve

Question 7

If the pilot burner fails to ignite, or if the pilot does go on, the gas burner fails to ignite a lockout switch will be energized after a short trial period of _____ seconds from the time of startup.
Select one:

A. 5 to 10
B. 15 to 30
C. 10 to 20
D. 20 to 40
E. 30 to 50

Answer 7

B. 15 to 30

Question 8

If the blower starts but stops again after 5-10 seconds:

Select one:
A. Check the low air pressure switch
B. Reset safety lock-out switch
C. Replace motor
D. Close the blower switch
E. Refer to manufacturers manual

Answer 8

A. Check the low air pressure switch

Question 9

The boiler vent valve is used for the purpose of allowing:

Select one:

A. Steam to enter while draining
B. Steam to escape while filling
C. Air to escape while draining
D. Air to escape while filling
E. Water to escape while filling

Answer 9

D. Air to escape while filling

Question 10

The switch in the operating control of a steam boiler is opened by:
Select one:

A. Falling steam pressure
B. Falling steam temperature
C. Falling water pressure
D. Rising steam pressure
E. Rising steam temperature

Answer 10

D. Rising steam pressure

Question 11

Before feedwater enters a boiler the feedwater pipe must be fitted with a:

Select one:
A. Stop valve between the check valve and the boiler
B. Check valve between the stop valve and the boiler
C. Ball valve between the check valve and the boiler
D. Gate valve between the check valve and the boiler
E. Globe valve between the check valve and the boiler

Answer 11

A. Stop valve between the check valve and the boiler

Question 12

The voltage supply generated by the thermocouple is usually not more than :

Select one:
A. 30 millivolts
B. 15 millivolts
C. 100 millivolts
D. 50 millivolts
E. 0 millivolts

Answer 12

A. 30 millivolts

Question 13

A heating boiler must have a permanently attached marker indicating:
Select one:

A. Lowest permissible water level
B. The maximum allowable working temperature
C. The maximum allowable working pressure
D. Highest permissible water level
E. Lowest permissible steam level

Answer 13

E. Lowest permissible steam level

Question 14

Quick closing gauge glass valves are operated by:

Select one:

A. Actuators
B. Levers and chains
C. Valve rods
D. Diaphragms
E. Solenoids

Answer 14

B. Levers and chains

Question 15

The low water level fuel cut-off will shut off the fuel to the heating boiler when the water level drops below:
Select one:

A. 50 mm(2 in) above the bottom of the gauge glass
B. 25 mm (1 in) above the bottom of the gauge glass
C. One half of the gauge glass
D. The lowest visible part of the gauge glass
E. The lowest permissible water level

Answer 15

D. The lowest visible part of the gauge glass

Question 16

The switch in the operating control of a hot water boiler is closed by:

Select one:
A. Falling water temperature
B. Falling water pressure
C. Falling steam temperature
D. Rising steam temperature
E. Rising water pressure

Answer 16

A. Falling water temperature

Question 17

A programming control on a natural draft gas fired boiler operate in the following sequence.
1. The main burner is ignited
2. The flame detector senses the flame and causes the main gas valve to open
3. The ignition transformer and pilot gas valve are de-energized and closed, if an interrupted pilot is used
4. The operating control initiates a startup
5. The load relay energizes the ignition transformer and the pilot gas valve

Select one:
A. 4,5,2,1,3
B. 2,5,1,4,3
C. 1,2,3,4,5
D. 3,2,1,5,4
E. 5,3,2,1,4

Answer 17

A. 4,5,2,1,3

Question 18

The discharge piping from the relief valve should be piped to a safe point for disposal and can be:
Select one:

A. Connected to the Deaerator
B. Connected to any drain
C. Connected to any vent
D. Terminated above a floor drain
E. Connected to the condensate tank

Answer 18

D. Terminated above a floor drain

Question 19

The “popping” pressure of a safety valve may be increased by:

Select one:
A. Raising the lifting lever
B. Decreasing the spring pressure
C. Lowering the adjusting ring
D. Increasing the spring pressure
E. Raising the adjusting ring

Answer 19

D. Increasing the spring pressure

Question 20

Boiler gauge glass packing nuts may be tightened:

Select one:
A. Once the glass has cooled to room temperature
B. At any time
C. Only hand tight
D. With a torque wrench
E. Once the pressure has been removed

Answer 20

E. Once the pressure has been removed