80-99 Flashcards
80.The gas meter for your boiler malfunctions and you have to shut off all gas. How can you keep your boiler on line? SPO 6-7-8
If you have an alternate fuel, hook up a bottle of propane with a regulator to the pilot.
81.Name five electrical devices used on a boiler. SPO 6-7-8 BOW 3-4
Low water alarm, induced or forced draft fans, oil pumps, flame controls, damper motors, flow switch, water level control, lights and CCTV cameras.
82.What is natural draft? What causes natural draft? SPO 6-7-8 LPB 2-3 BOW 2-3-4
When the weight of the warmer air in the stack is less than the cool air around the stack, it causes an upward flow, pulling air through the furnace.
The heavier, cool air outside the stack gives a push to the warm lighter air in the stack causing air to flow through the furnace.
83.How is the flow of natural draft controlled? LPB 2-3 BOW 2-3-4
By dampers mounted in the breeching and/or the burner and are operated by automatic controls either electric or pneumatic.
84.Does the diameter or height of a stack have an effect on the draft? SPO 6-7-8 BOW 2-3-4
Yes. Both of them. Height determines velocity and diameter determines volume.
85.How is draft measured? What is a draft gauge used for and how does it work? SPO 6-7-8 LPB 2-3 BOW 2-3-4
In inches of water with a manometer or “U” gauge.
A draft gauge is used to measure the pressure differences of the boiler room and inside the setting or firebox.
One tube end is connected into the breeching and the other end is open to the boiler room.
Pressure moves the liquid in the tube. The difference is read in tenths of an inch.
86.When would you employ forced draft? SPO 6-7-8 LPB 2-3 BOW 2-3-4
When you fail to have insufficient natural draft through the boiler.
87.What is mechanical draft? Name and describe three types. SPO 6-7-8 LPB 2-3 BOW 2-3-4
The adding of fans to make up for insufficient natural draft
INDUCED DRAFT is a fan in the breeching between the boiler and the stack, pulling air through the furnace. The boiler operates below atmospheric pressure
FORCED DRAFT is a fan at the point of air entry, pushing air through the furnace. The boiler operates above atmospheric pressure.
BALANCED DRAFT is the addition of both forced and induced fans and the boiler operates slightly below atmospheric pressure, about .05 to.10 inches water column.
- What is a pressurized furnace? SPO 6-7-8 BOW 2-3-4
A pressurized furnace has a fan placed at the point of air entry to maintain the furnace above atmospheric pressure, pushing the products of combustion through the furnace and out the stack.
- How do you control the dampers on a large fan from a remote location? BOW 3-4
The control panel sends a signal to pneumatic or electric actuators that move the damper linkages.
- lf maintenance was done on your boiler, it was put back in operation and the stack
temperature was higher than normal, what would you look for as the cause?
If it was a water tube boiler, it will most likely be defective or missing baffles.
If it was a fire tube boiler, it could be missing turbulators or have blocked tubes
91.Where are turbulators used and what is their purpose? BOW 2-3-4
They are used in the tubes of fire tube boilers to increase heat transfer in the tubes.
92.How often should you test the low water cutoffs and fully describe 3 ways of safely doing this? LPB 2-3 BOW 2-3-4
At least once a shift, furiously blowdown the water column and insure that the water returns rapidly and smoothly into the glass.
Once a month the EVAPORATION METHOD is done by securing the feed pump and allowing the water to evaporate from the boiler on LOW FIRE ONLY. Do this with supervision and remain alert during the test.
Once a month the SLOW DRAIN method is done by securing the feed pump and SLOWLY blow down the boiler on LOW FIRE ONLY. Do this with supervision and remain alert during the test
93.How often should you blow down your sight glass? What would you do if the glass broke while the boiler was operating? SPO 6-7-8 LPB 2-3 BOW 2-3-4
Blow down the glass at the start of each shift.
Put on PPE and operate gauge glass shut off valves. Use Tri-cocks to check water level during the repair. Open blow down for the gauge glass. Remove all broken glass. After installing the new glass with new washers, very slowly open the top shut off to warm the glass. Close the blow down then slowly open the bottom shut off.
94.What would cause a false level in the sight glass? SPO 6-7-8 LPB 2-3 BOW 2-3-4 C
Sight glass valve closed. Sediment accumulation.
Foaming because of overfiring or high TDS (Totally Dissolved Solids)
Improperly installed water column.
Leaking top sight glass washer.
