Book 1 Chapter 10: Boiler Programming Controls

Question 1

What is the name given to the component that coordinates and sequences the boiler operation?
A) programming controller
B) header pressure controller
C) air/fuel ratio controller
D) boiler master

Answer 1

A) programming controller

Question 2

What is the device used to determine that the fan motor is working?
A) motor contactor
B) air flow switch
C) power amperage draw meter
D) indicator light

Answer 2

B) air flow switch

Question 3

Which of the following would not cause the main burner to stay on during low-fire operation mode?
A) inoperative damper motor
B) damper positioning switch is in the wrong position
C) the boiler pressure is below the high-low fire control setting
D) a defective high-low modulating control

Answer 3

C) the boiler pressufre is below the high-low fire control setting

Question 4

Which of the following is not a possible causes of the damper motor failing to operate?
A) High-low fire or modulating control set improperly
B) Loss of fluid in the motor float chamber
C) Positioning switch in wrong position
D) Motor contracts malfunctioning
E) A loose or jammed linkage

Answer 4

B) Loss of fluid in the motor float chamber

Question 5

The operating pressure control will control the:
A) Boiler furnace pressure
B) Steam pressure in the boiler
C) Gas pressure to the burner
D) Water pressure to the boiler
E) Steam pressure in the steam header

Answer 5

B) Steam pressure in the boiler

Question 6

Automatic boiler programming controls may use:
A) All answers shown
B) Interlocking devices
C) A modulating control system
D) An on-off of two-position control switch
E) High-low fire control

Answer 6

A) All answers shown

Question 7

To meet the programmed control startup conditions, the automatic boiler liquid fuel manual valves should be opened:
A) Immediately after completion of the pilot flame trial
B) With the automatic main burner fuel valve
C) After pre-purge and just prior to pilot ignition
D) Prior to pre-purging
E) After the automatic main burner fuel valve opens

Answer 7

D) Prior to pre-purging

Question 8

When the safety devices and limit controls on boilers, are activated, they shut off the:
A) Flue gas flow
B) Fuel flow
C) Feedwater flow
D) Combustion
E) Steam flow

Answer 8

B) Fuel flow

Question 9

If pilot ignition has not taken place, the oil fired boiler:
A) Will attempt restart after reset and the lock out switch has cooled down
B) Does not need to be purged again
C) Will be able to be restarted immediately
D) Will start after reset
E) Will restart when low airflow switch is closed

Answer 9

A) Will attempt restart after reset and the lock out switch has cooled down

Question 10

On a gas fired automatic boiler a normal programmed start-up takes approximately:
A) 55 seconds
B) 27-40 seconds
C) 120 seconds
D) 70 seconds
E) 105 seconds

Answer 10

E) 105 seconds

Question 11

Boiler furnaces are purged:
A) To allow any hot refractory to completely cool
B) So that combustibles are fully removed prior to ignition
C) So that the operator can check the fuel and water systems
D) So that the programmer has time to verify permissiveness of interlocks
E) In order to allow combustion gases to accumulate prior to ignition

Answer 11

B) So that combustibles are fully removed prior to ignition

Question 12

In the following start up and shut down sequence for gas fired boilers, which steps are out of order?
1. Starting switch closed. Operating control in cut in position. Master relay energized. Timer starts. Fan starts. Programmer takes control of damper motor. Purge initiated at maximum airflow
2. Low airflow switch closed
3. Damper placed in low fire position for purge at reduced flow. Low fire switch must close for ignition to take place
4. Flame relay switch is open
5. End of purge period. Ignition energized. Pilot gas valve opens. Start of trial period. When scanner senses pilot flame, the flame relay closes.
6. Main gas valve is energized, main burner lights. Starts of main burner ignition
7. Pilot valve and ignition de-energized. Programmer releases control of damper motor. Damper and fuel valve are now placed in high fire position by the modulating operating if the boiler is on automatic control, or they are placed on the demand setting of the firing rate selector switch if the boiler is on manual control.
8. End of start cycle, beginning of normal firing period. Timer motor stops, burner and blower remain in operation until heat demand is satisfied and operating controls reach their cut-out points
9. Operating control opens. Master relay and fuel valve de-energize. Scanner ceases to sense flame. Flame relay opens. Timer restarts. Programmer takes control of modulating motor and holds it in low fire position. Start of after-purge period at low air flow.
10. End of after-purge period. Blower motor stops, timer stops. The system is now ready again for a restart whenever operation control reaches its cut-in point.

A) 5,6
B) None are out of order
C) 8,9
D) 1,2
E) 10, 5

Answer 12

B) None are out of order

Question 13

During the startup of an oil fired boiler at the end of the purge the timer:
A) Shuts down
B) Goes through an ignition trial
C) Energizes the ignition transformer
D) Opens the pilot valve
E) Opens the fuel valve

Answer 13

C) Energizes the ignition transformer

Question 14

For programmed startup of boilers with Natural Draft the electrical circuit to the main gas valve is closed:
A) During pilot ignition
B) When the flame detector senses the Pilot flame
C) While purging
D) Before purging
E) When the water level is high

Answer 14

B) When the flame detector senses the Pilot flame

Question 15

Which of the following is not required before starting using programming control?
A) Main gas valve closed
B) Gas pressure above low pressure cutoff
C) Main power on
D) Water temp below cut in
E) Water level above cutoff

Answer 15

A) Main gas valve closed

Question 16

The two type of boiler combustion control include:
1. On-Off
2. Automatic
3. Modulating
4. Manual

A) 2,4
B) 2,3
C) 3,4
D) 1,2
E) 1,3

Answer 16

E) 1,3

Question 17

A programming control on a natural draft gas fired boiler operates 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

A) 5,3,2,1,4
B) 3,2,1,5,4
C) 2,5,1,4,3
D) 4,5,2,1,3
E) 1,2,3,4,5

Answer 17

D) 4,5,2,1,3

Question 18

If the combustion control safety lock-out switch is tripped:
A) Refer to manufacturer’s manual
B) Close the blower switch
C) Reset safety lock-out switch
D) Check the low air pressure switch
E) Replace motor

Answer 18

C) Reset safety lock-out switch

Question 19

Before a steam or hot water boiler can be started by a programming control, all but one of the following conditions must be fulfilled:
A) The water in the boiler drum must be above the cut-off point of the low-water fuel cut-off
B) All manually operated valves in the fuel lines to the pilot and main burner must be closed
C) The steam pressure or water temperature must be at or below the cut-in setting of the operating control
D) The main power switch or breaker must be closed
E) If the boiler is gas-fired, the fuel supply pressure to the burner valves must be above the cutout point of the low gas pressure cut-off

Answer 19

B) All manually operated valves in the fuel lines to the pilot and main burner must be closed

Question 20

The switch in the operating control of a steam boiler is closed by:
A) Falling steam temperature
B) Falling water pressure
C) Rising steam pressure
D) Falling steam pressure
E) Rising steam temperature

Answer 20

D) Falling steam pressure

Question 21

If the burner fails to ignite during the trial period, the lock-out switch is activated and the boiler cannot be restarted until:
A) The switch resets automatically
B) The fuel valve has been reset
C) The furnace has been purged
D) The switch has been manually reset
E) A short time period has passed

Answer 21

D) The switch has been manually reset

Question 22

Purging a furnace means forcing a flow of:
A) Water through a furnace for a set period of time when the burner is in operation
B) Air through a furnace for a set period of time when the burner is not in operation
C) Fuel through a furnace for a set period of time when the burner is not in operation
D) Air through a furnace for a set period of time when the burner is in operation
E) Fuel through a furnace for a set period of time when the burner is in operation

Answer 22

B) Air through a furnace for a set period of time when the burner is not in operation

Question 23

The programmed startup sequence of oil-fired boilers with no pilot light is as follows:
1. The flame detector senses the flame and causes the flame relay to close
2. The spark from the ignition transformer ignites the main burner
3. The load relay energizes the ignition transformer, fuel oil shut-off valve, and motor driving the air fan and fuel pump
4. The ignition transformer is then de-energized
5. The operating control closes a switch

A) 5,3,2,1,4
B) 1,2,3,4,5
C) 4,5,2,1,3
D) 3,2,1,5,4
E) 2,5,1,4,3

Answer 23

A) 5,3,2,1,4

Question 24

The switch in the operating control of a steam boiler is opened by:
A) Rising steam temperature
B) Rising steam pressure
C) Falling water pressure
D) Falling steam pressure
E) Falling steam temperature

Answer 24

B) Rising steam pressure

Question 25

The switch in the operating control of a hot water boiler is opened by:
A) Rising steam temperature
B) Rising water pressure
C) Falling water temperature
D) Falling water pressure
E) Rising water temperature

Answer 25

E) Rising water temperature