CHAPTER 8 Flashcards
The high gas pressure cut-off switch can be tested by:
Select one:
A.
Slowly raising the boiler pressure above the operating setpoint
B.
Slowly covering the air supply to the fan
C.
Quickly closing the main burner shut-off valve
D.
Slowly closing the main gas valve
E.
Closing the main gas valve quickly
C.
Quickly closing the main burner shut-off valve
Damper position switches are found on boilers with the following burner control systems:
1. On-Off control
2. High-Low control
3. Modulating control
4. High Limit control
Select one:
A.
2, 3
B.
4, 5
C.
3, 4
D.
1, 2
E.
1, 3
A. 2, 3
2. High-Low control
3. Modulating control
The Modulating fire control system uses _____ to control the combustion process.
Select one:
A.
Fuel on-off control
B.
Variable fuel/air flow
C.
Fixed fuel flow and variable air flow
D.
Air on-off control
E.
Fixed air flow and variable fuel flow
B.
Variable fuel/air flow
The low gas pressure cut-off switch can be tested by:
Select one:
A.
Slowly closing the main gas valve
B.
Quickly closing the main burner shut-off valve
C.
Closing the main gas valve quickly
D.
Slowly covering the air supply to the fan
E.
Slowly raising the boiler pressure above the operating setpoint
A.
Slowly closing the main gas valve
An automatic/manual selector switch is provided on a boiler with the following burner control system.
Select one:
A.
Operating limit fire control
B.
On-Off fire control
C.
High limit fire control
D.
Modulating fire control
E.
High-Low fire control
D.
Modulating fire control
The hot water heating boiler burner control uses the _____ as the sensed variable.
Select one:
A.
Boiler water temperature
B.
Boiler water pressure
C.
Boiler steam temperature
D.
Drum water level
E.
Feedwater pressure
A.
Boiler water temperature
The On-Off method of steam heating boiler burner control uses the _____ as the sensed variable.
Select one:
A.
Boiler steam temperature
B.
Drum water level
C.
Boiler steam flow
D.
Feedwater pressure
E.
Boiler steam pressure
E.
Boiler steam pressure
During boiler operation if the combustion air pressure drops to low the _____ switch will de-energize the fuel valve.
Select one:
A.
Low gas pressure
B.
Low air pressure
C.
High limit
D.
Low water level
E.
High gas pressure
B.
Low air pressure
If the pressure of the gas supplied to the burner increases beyond the maximum required for safe combustion the _____ switch will de-energize the fuel valve.
Select one:
A.
Low gas pressure
B.
Low water level
C.
High gas pressure
D.
Low air pressure
E.
High limit
C.
High gas pressure
The High-Low fire control method requires two pressure controllers, one is called the high-low fire control and the other is called the:
Select one:
A.
On-Off fire control
B.
High limit fire control
C.
Operating limit fire control
D.
Modulating fire control
E.
Operating limit pressure control
E.
Operating limit pressure control
The high limit control of a steam heating boiler should operate at the:
Select one:
A.
Between the set pressures of the operating control and safety valve
B.
Set pressure of the safety valve
C.
Blowdown pressure of the safety valve
D.
Maximum allowable working pressure
E.
Cut-out pressure of the operating control
A.
Between the set pressures of the operating control and safety valve
The On-Off pressure controller contains two adjustable variables, one is the pressure adjustment and the other is the:
Select one:
A.
Cut-in Lever
B.
Leveling indicator
C.
Differential adjustment
D.
Pressure bellows
E.
Operating lever
C.
Differential adjustment
The low air pressure cut-off switch can be tested by:
Select one:
A.
Closing the main gas valve quickly
B.
Slowly covering the air supply to the fan
C.
Quickly closing the main burner shut-off valve
D.
Slowly raising the boiler pressure above the operating setpoint
E.
Slowly closing the main gas valve
B.
Slowly covering the air supply to the fan
Three of the four distinct methods of burner operation control for a steam boiler are:
1. On-Off control
2. Damping control
3. Modulating control
4. High Limit control
5. Multiple burner control
Select one:
A.
1, 3, 4
B.
1, 2, 3
C.
2, 3, 5
D.
2, 3, 4
E.
3, 4, 5
A. 1, 3, 4
1. On-Off control
3. Modulating control
4. High Limit control
Controls found on heating boilers include:
1. Operating controls
2. Pressure relief controls
3. High limit cut-off switches
4. Condensate level controls
5. Low limit cut-off switches
Select one:
A.
1, 2, 3
B.
2, 3, 4
C.
3, 4, 5
D.
1, 3, 5
E.
3, 4, 5
D. 1, 3, 5
1. Operating controls
3. High limit cut-off switches
5. Low limit cut-off switches
