Boiler combustion controls Flashcards
The programming control relay of a flame safeguard device:
A) Should occasionally have the dust blown out of it
B) Requires an adjustment check monthly by the chief engineer
C) Needs an electrician to work on it
D) Requires yearly maintenance tune up by the operator
E) Can be bypassed
A) Should occasionally have the dust blown out of it
The flame scanner lens is:
A) Concave B) Concentric C) Cleanable D) Easily changeable E) Inaccessible
C) Cleanable
The flame scanner:
A) Is not sensitive to electromagnetic radiation
B) Must be protected from drafts
C) All of the above
D) Should be cool enough to hold in the hand during operation
E) Should be shielded from light
D) Should be cool enough to hold in the hand during operation
One type of flame failure device uses a lead sulphide cell that is sensitive to:
A) Ultraviolet rays B) The color of the fuel C) Infrared rays D) Radio waves E) Temperature
C) Infrared rays
The fuel to a boiler burner should be shut off immediately if it fails to ignite in order to:
A) Prevent boiler corrosion B) Prevent furnace explosions C) Prevent spills D) Save fuel E) Save power
B) Prevent furnace explosions
A thermocouple:
A) Produces an electric signal B) Senses changes in fuel pressure C) Senses changes in air pressure D) Senses infrared light from the flame E) Consists of two similar wires
A) Produces an electric signal
Thermocouples are connected in series to:
A) Increase the sensitivity of the detection system
B) Provide a spare thermocouple in case one fails
C) Generate a lower voltage
D) Monitor more than one flame source
E) Generate a higher voltage
E) Generate a higher voltage
The flame scanner sight tube:
A) Should be free of obstructions
B) Should be lubricated often
C) Should be shielded from the burner radiation
D) Is filled with protective packing
E) Should be aimed at the rear of the furnace
A) Should be free of obstructions
Flame Rods:
A) Require frequent filing of electrical contacts to prevent corrosion of the device
B) Should shut off the fuel within four seconds of flame failure
C) Are commonly used with oil-fired burners
D) Are rarely used as they are unreliable and require frequent maintenance
E) Should not be exposed to temperatures above 100°C
B) Should shut off the fuel within four seconds of flame failure
A flame rod:
A) Is used for gas and oil fired burners
B) Senses the temperature of the flame
C) Is used to light the main burner
D) Forms an electric circuit with the rod, flame and burner
E) Forms an electric circuit with the rod, flame and relay
D) Forms an electric circuit with the rod, flame and burner
The Flame Rod Boiler Flame Failure detector is commonly only used with:
A) Electric heaters B) Solid fuels C) Oil burners D) Coal burners E) Gas burners
E) Gas burners
