A lockout switch will energize after __ to __ seconds.

A lockout switch will energize after __ to __ seconds.

a. 5 to 10
b. 15 to 30
c. 10 to 15
d. 20 to 40
e. 15 to 25






Answer: B

On-off controls are common on?

On-off controls are common on?

a. firetube boilers
b. watertube boilers
c. small package boilers
d. large package boilers
e. all of the above

Answer: C

If the damper motor does not operate on a boiler which one would NOT be the possible cause?

If the damper motor does not operate on a boiler which one would NOT be the possible cause?

a. Damper positioning switch in wrong position.
b. Linkage loose or jammed.
c. The lock-out switch has tripped.
d. Motor does not drive to "open" or "close" during prepurge or close on burner shutdown.
e. Motor does not operate on demand.

Answer: C

If the burner stays on low fire on a boiler which one would NOT be the possible cause?

If the burner stays on low fire on a boiler which one would NOT be the possible cause?

a. Boiler pressure above high-low fire control setting.
b. Damper positioning switch in wrong
c. Inoperative damper motor.
d. Flame detector weak or defective.
e. Defective high-low fire or modulating control.





Answer: D

If shutdown occurs during firing a boiler which one would NOT be the possible cause?

If shutdown occurs during firing a boiler which one would NOT be the possible cause?

a. Loss or stoppage of fuel
b. Defective fuel valve, loose electrical connections
c. Flame detector weak or defective
d. Lens dirty or sight tube obstructed
e. Boiler pressure above high-low fire control setting.






Answer: E

If pilot or low-fire flame occurs in a boiler which one would NOT be the possible cause?

If pilot or low-fire flame occurs in a boiler which one would NOT be the possible cause?

a. Low fire switch open.
b. Insufficient pilot or low fire flame.
c. Supply to main nozzles restricted or cut off.
d. Inoperative programmer.




Answer: A