MD STATIONARY ENGINEER GRADE 2 EXAM
2026 PROFESSIONAL CERTIFICATION
PREPARATION COMPENDIUM
◉ What is the first indication of a low water condition Answer: A red
hot crown sheet
◉ If a boiler exceeds 100psi it must have how many blowdowns?
Answer: 2
◉ What is the appropriate test for checking porosity of the metal?
Answer: PULSE ECHO ( A TYPE OF ULTRASONIC)
◉ What chemicals are used to combat corrosion? Answer: Sodium
Sulfite; hydrazine; catalied hydrazine
◉ If your boiler water has a PH of .5 what compound type do you
add to neutralize it? Answer: BASES - THEY REACT WITH ACIDS TO
FORM A SALT
◉ What level of deionized water alkalinityis permitted for a 600 psi
boiler? Answer: 250 PPM
,◉ What can oxygen cause in a system Answer: PITTING CORROSION
◉ In a vertical boiler where is the first place to check for thinning
tubes? Answer: WATER LEGS especially at the bottom or on the
combustion side at the upper ends of the tubes.
◉ What produces soft scale? Answer: Calcium and magnesium
carbonate and magnesium clorine
◉ Hideout in a boiler causes what to precipitate? Answer: Sodium
phosphate
◉ What is main cause of a generating tube failure? Answer:
overheating at the lower tubes due to scale sludge and poor
circulation
◉ What refrigerant is flammable and non toxic ? Answer: Propane
◉ What refrigerant class is Ammonia R 717? Answer: B2
◉ What is the purpose of a condensor in a refrigerant system?
Answer: to bring refrigerant to a liquid state
,◉ Why is oil in a refrigerating system? Answer: lubricates and cools
compressor
◉ How is moisture removed from a refrigerant system? Answer:
filter dryer
◉ What type of gas DONT you use to leak test an AC system?
Answer: OXYGEN
◉ What is the maximum voltage on a boiler control circuit? Answer:
150 VOLTS
◉ A fuel oil that has an API of 32 has how many btus per lb of
heating? Answer: 19490
◉ Which fuel oils need heating? Answer: #4;#5;#6
◉ What size pipe is used as a header in a boiler operating at 100 psi?
Answer: 6 inches
◉ What function can an operator contribute towards boiler
function? Answer: saftey - efficiency - log plant readings
, ◉ How is heat transferred in a boiler ? Answer: CONVECTION -
CONDUCTION - RADIATION
◉ What is not an organic sludge conditioner? Answer: Amines
◉ Which by-product has the largest heating value? Answer: Butane
◉ An increase in 10-20 degrees can reduce creep life by how manuy
years Answer: 10-20
◉ which coal burns with a yellow flame? Answer: Bituminous
◉ What nondestructive testing is best for testing thickness of plates
and tubes? Answer: Ultrasound
◉ On a 2"valve auxillary staem what valves are needed? Answer:
Single supply OS&Y
◉ What are the min and max size of a safely valve per code for
boilers? Answer: Min 3/4 and max 4 1/2
◉ What stamp is put on a safety valve after its been repairs?
Answer: VR stamp
2026 PROFESSIONAL CERTIFICATION
PREPARATION COMPENDIUM
◉ What is the first indication of a low water condition Answer: A red
hot crown sheet
◉ If a boiler exceeds 100psi it must have how many blowdowns?
Answer: 2
◉ What is the appropriate test for checking porosity of the metal?
Answer: PULSE ECHO ( A TYPE OF ULTRASONIC)
◉ What chemicals are used to combat corrosion? Answer: Sodium
Sulfite; hydrazine; catalied hydrazine
◉ If your boiler water has a PH of .5 what compound type do you
add to neutralize it? Answer: BASES - THEY REACT WITH ACIDS TO
FORM A SALT
◉ What level of deionized water alkalinityis permitted for a 600 psi
boiler? Answer: 250 PPM
,◉ What can oxygen cause in a system Answer: PITTING CORROSION
◉ In a vertical boiler where is the first place to check for thinning
tubes? Answer: WATER LEGS especially at the bottom or on the
combustion side at the upper ends of the tubes.
◉ What produces soft scale? Answer: Calcium and magnesium
carbonate and magnesium clorine
◉ Hideout in a boiler causes what to precipitate? Answer: Sodium
phosphate
◉ What is main cause of a generating tube failure? Answer:
overheating at the lower tubes due to scale sludge and poor
circulation
◉ What refrigerant is flammable and non toxic ? Answer: Propane
◉ What refrigerant class is Ammonia R 717? Answer: B2
◉ What is the purpose of a condensor in a refrigerant system?
Answer: to bring refrigerant to a liquid state
,◉ Why is oil in a refrigerating system? Answer: lubricates and cools
compressor
◉ How is moisture removed from a refrigerant system? Answer:
filter dryer
◉ What type of gas DONT you use to leak test an AC system?
Answer: OXYGEN
◉ What is the maximum voltage on a boiler control circuit? Answer:
150 VOLTS
◉ A fuel oil that has an API of 32 has how many btus per lb of
heating? Answer: 19490
◉ Which fuel oils need heating? Answer: #4;#5;#6
◉ What size pipe is used as a header in a boiler operating at 100 psi?
Answer: 6 inches
◉ What function can an operator contribute towards boiler
function? Answer: saftey - efficiency - log plant readings
, ◉ How is heat transferred in a boiler ? Answer: CONVECTION -
CONDUCTION - RADIATION
◉ What is not an organic sludge conditioner? Answer: Amines
◉ Which by-product has the largest heating value? Answer: Butane
◉ An increase in 10-20 degrees can reduce creep life by how manuy
years Answer: 10-20
◉ which coal burns with a yellow flame? Answer: Bituminous
◉ What nondestructive testing is best for testing thickness of plates
and tubes? Answer: Ultrasound
◉ On a 2"valve auxillary staem what valves are needed? Answer:
Single supply OS&Y
◉ What are the min and max size of a safely valve per code for
boilers? Answer: Min 3/4 and max 4 1/2
◉ What stamp is put on a safety valve after its been repairs?
Answer: VR stamp
