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Louisiana (New Orleans) Second Class Stationary
Boilers 661-LA/661 Exam QUESTIONS AND
DETAILED SOLUTIONS JUST RELEASED
Louisiana (New Orleans) Second Class Stationary Boilers 661-LA/661 Exam
Exam Coverage Areas (Most Tested Points)
1. Boiler Design & Types (ASME Section I) - Fire-tube vs. water-tube boilers, HRT, Scotch Marine,
D-type, components (steam drum, mud drum, tube sheets), superheaters, economizers
2. Thermodynamics & Heat Transfer - First Law of Thermodynamics, sensible heat, latent heat of
vaporization, radiation/convection/conduction mechanisms
3. Safety Devices & Fittings (ASME Code) - Safety valve settings (6% above MAWP), ASME pop
test, Low-Water Cutoff (LWCO) devices, gauge glass blowdown, pressure gauges with pigtail
siphon
4. Water Treatment & Chemistry - Scale control with phosphates, oxygen scavengers (sodium
sulfite), pH control (caustic soda), deaeration, bottom vs. surface blowdown, TDS control
5. Combustion & Draft Systems - The 3 T's (Time, Temperature, Turbulence), forced draft, induced
draft, balanced draft, fuel oil viscosity control, atomization
6. Boiler Operation: Start-up & Shutdown - Water level verification first, slow warm-up to prevent
thermal stress, fuel secure first for shutdown, cut-in procedures
7. Controls & Instrumentation - Master controller (fuel modulation), flame scanners, feedwater
pump operation, conductivity meters, pH meters
8. Louisiana & New Orleans Regulations - LA R.S. §33:4814 (Board authority), license posting in
engine room, annual renewal, license required for cities >50k population
9. Maintenance & Inspections - Hydrostatic test (1.5 x MAWP), ASME stamp requirements, soot
blowing, chemical cleaning, thermal expansion accommodation
10. Piping, Pumps & Valves - Check valves (prevent backflow), quick-opening vs. slow-opening
blowdown valves, feedwater pump types, pigtail siphon for pressure gauges
Question 1
When you are starting up a cold water-tube boiler after it has been shut down for the weekend and you
see that the gauge glass shows water at the normal level while the low-water cutoff control displays a
low water alarm that prevents the burner from lighting, what is the most likely cause of this problem
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that you must address immediately?
A) The feedwater pump is cavitating and not supplying enough water
B) The LWCO is giving a false reading because it is scaled or blocked
C) The main steam stop valve is open and causing a pressure drop
D) The safety valve is leaking and reducing the boiler pressure
Answer: B
Rationale: Even if the glass shows water, the LWCO chamber could be blocked or the float stuck due to
sediment, rust, or thermal expansion, causing a false reading. Low water cutoffs can develop "memory"
or false readings that prevent burner operation.
Question 2
A fireman reports to you that the furnace pressure is fluctuating violently and the flame is puffing back
through the burner, and upon checking the draft gauges you see the induced draft fan is running but the
furnace draft is positive at +0.2 inches of water column, so what is the immediate danger that you must
recognize and address in this situation?
A) Loss of boiler efficiency that will increase fuel consumption
B) Rolling water level in the gauge glass making it hard to read
C) Blowback of flame into the fire room creating a serious safety hazard
D) Reduced steam pressure that will affect plant operations
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Answer: C
Rationale: Positive furnace pressure means combustion gases are not being properly drawn through the
boiler. This can cause blowback of the flame into the fire room, creating a serious safety hazard for
personnel. Induced draft fans are designed to create negative pressure in the furnace.
Question 3
You are performing a hydrostatic test on a boiler with a maximum allowable working pressure of 200 psi
and you need to know the correct pressure to apply for this test, so what is the proper test pressure
according to ASME code requirements?
A) 150 psi which is below the operating pressure
B) 200 psi which equals the maximum working pressure
C) 300 psi which is 1.5 times the maximum working pressure
D) 400 psi which is double the maximum working pressure
Answer: C
Rationale: A hydrostatic test is typically performed at 1.5 times the maximum allowable working
pressure (MAWP). For a boiler with MAWP of 200 psi, the test pressure would be 300 psi. Exceeding this
risks permanent deformation of the pressure vessel.
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Question 4
During the morning inspection you notice that the boiler pressure is 150 psi but the steam coming out of
the gauge glass is showing a water level that is low, so what is the most likely cause of this discrepancy
between the gauge glass reading and the actual boiler conditions?
A) The gauge glass is leaking steam and needs to be replaced
B) The gauge glass has not been blown down and is giving a false reading
C) The safety valve is open and venting steam to the atmosphere
D) The feedwater pump is operating at too high a pressure
Answer: B
Rationale: The gauge glass must be blown down daily (at least once per shift) to verify accuracy and
prevent sediment buildup that can give false readings. The steam space should appear dark or black in a
properly functioning gauge glass.
Question 5
You find that the oxygen scavenger feed pump has failed and sodium sulfite is not being added to the
boiler water, so what is the most serious consequence of this failure that you must address to prevent
damage to the boiler system?
A) Hydrogen embrittlement of the boiler tubes
B) Oxygen pitting corrosion in the economizer and boiler
Louisiana (New Orleans) Second Class Stationary
Boilers 661-LA/661 Exam QUESTIONS AND
DETAILED SOLUTIONS JUST RELEASED
Louisiana (New Orleans) Second Class Stationary Boilers 661-LA/661 Exam
Exam Coverage Areas (Most Tested Points)
1. Boiler Design & Types (ASME Section I) - Fire-tube vs. water-tube boilers, HRT, Scotch Marine,
D-type, components (steam drum, mud drum, tube sheets), superheaters, economizers
2. Thermodynamics & Heat Transfer - First Law of Thermodynamics, sensible heat, latent heat of
vaporization, radiation/convection/conduction mechanisms
3. Safety Devices & Fittings (ASME Code) - Safety valve settings (6% above MAWP), ASME pop
test, Low-Water Cutoff (LWCO) devices, gauge glass blowdown, pressure gauges with pigtail
siphon
4. Water Treatment & Chemistry - Scale control with phosphates, oxygen scavengers (sodium
sulfite), pH control (caustic soda), deaeration, bottom vs. surface blowdown, TDS control
5. Combustion & Draft Systems - The 3 T's (Time, Temperature, Turbulence), forced draft, induced
draft, balanced draft, fuel oil viscosity control, atomization
6. Boiler Operation: Start-up & Shutdown - Water level verification first, slow warm-up to prevent
thermal stress, fuel secure first for shutdown, cut-in procedures
7. Controls & Instrumentation - Master controller (fuel modulation), flame scanners, feedwater
pump operation, conductivity meters, pH meters
8. Louisiana & New Orleans Regulations - LA R.S. §33:4814 (Board authority), license posting in
engine room, annual renewal, license required for cities >50k population
9. Maintenance & Inspections - Hydrostatic test (1.5 x MAWP), ASME stamp requirements, soot
blowing, chemical cleaning, thermal expansion accommodation
10. Piping, Pumps & Valves - Check valves (prevent backflow), quick-opening vs. slow-opening
blowdown valves, feedwater pump types, pigtail siphon for pressure gauges
Question 1
When you are starting up a cold water-tube boiler after it has been shut down for the weekend and you
see that the gauge glass shows water at the normal level while the low-water cutoff control displays a
low water alarm that prevents the burner from lighting, what is the most likely cause of this problem
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that you must address immediately?
A) The feedwater pump is cavitating and not supplying enough water
B) The LWCO is giving a false reading because it is scaled or blocked
C) The main steam stop valve is open and causing a pressure drop
D) The safety valve is leaking and reducing the boiler pressure
Answer: B
Rationale: Even if the glass shows water, the LWCO chamber could be blocked or the float stuck due to
sediment, rust, or thermal expansion, causing a false reading. Low water cutoffs can develop "memory"
or false readings that prevent burner operation.
Question 2
A fireman reports to you that the furnace pressure is fluctuating violently and the flame is puffing back
through the burner, and upon checking the draft gauges you see the induced draft fan is running but the
furnace draft is positive at +0.2 inches of water column, so what is the immediate danger that you must
recognize and address in this situation?
A) Loss of boiler efficiency that will increase fuel consumption
B) Rolling water level in the gauge glass making it hard to read
C) Blowback of flame into the fire room creating a serious safety hazard
D) Reduced steam pressure that will affect plant operations
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Answer: C
Rationale: Positive furnace pressure means combustion gases are not being properly drawn through the
boiler. This can cause blowback of the flame into the fire room, creating a serious safety hazard for
personnel. Induced draft fans are designed to create negative pressure in the furnace.
Question 3
You are performing a hydrostatic test on a boiler with a maximum allowable working pressure of 200 psi
and you need to know the correct pressure to apply for this test, so what is the proper test pressure
according to ASME code requirements?
A) 150 psi which is below the operating pressure
B) 200 psi which equals the maximum working pressure
C) 300 psi which is 1.5 times the maximum working pressure
D) 400 psi which is double the maximum working pressure
Answer: C
Rationale: A hydrostatic test is typically performed at 1.5 times the maximum allowable working
pressure (MAWP). For a boiler with MAWP of 200 psi, the test pressure would be 300 psi. Exceeding this
risks permanent deformation of the pressure vessel.
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Question 4
During the morning inspection you notice that the boiler pressure is 150 psi but the steam coming out of
the gauge glass is showing a water level that is low, so what is the most likely cause of this discrepancy
between the gauge glass reading and the actual boiler conditions?
A) The gauge glass is leaking steam and needs to be replaced
B) The gauge glass has not been blown down and is giving a false reading
C) The safety valve is open and venting steam to the atmosphere
D) The feedwater pump is operating at too high a pressure
Answer: B
Rationale: The gauge glass must be blown down daily (at least once per shift) to verify accuracy and
prevent sediment buildup that can give false readings. The steam space should appear dark or black in a
properly functioning gauge glass.
Question 5
You find that the oxygen scavenger feed pump has failed and sodium sulfite is not being added to the
boiler water, so what is the most serious consequence of this failure that you must address to prevent
damage to the boiler system?
A) Hydrogen embrittlement of the boiler tubes
B) Oxygen pitting corrosion in the economizer and boiler
