Z-51 Written Test Exam (Latest Update
2026) UPDATE!! (Recent exam) Merged
With Correct Complete Solutions
Already Graded A+ || 2026-2027 Latest
Update!!!
In a steam turbine, what is the function of a Kingsbury thrust bearing?
A) Maintain first stage steam pressure.
B) Compensate for coupling misalignment.
C) Adjust shaft torque at start up.
D) Maintain axial positioning of the rotor shaft. - ANSWER-D) Maintain
axial positioning of the rotor shaft.
The ratio of actual pressure of water pressure in the atmosphere to
the saturated pressure of given temperature is
,A) partial pressure.
B) relative humidity.
C) humidity effect.
D) absolute humidity. - ANSWER-
The total amount of heat to be removed from the refrigerant in a
condenser equals the heat picked up in the
A) evaporator plus the heat of compression.
B) evaporator.
C) evaporator plus the heat of included non-condensable.
D) evaporator less the heat given up in the muffler. - ANSWER-
When must the Fire Department be notified that a fire protection
system is out of service?
A) The manual pull alarm station in the lobby will be out of service for
4 hours.
B) Four sprinkler heads on a same floor of your building will be out of
service for 2 hours.
C) The sprinkler system will be out of service on 1st and 2nd floors.
D) The fire alarm system is out of service in the refrigerating system
room for g hours. - ANSWER-C) The sprinkler system will be out of
service on 1st and 2nd floors.
,Hot work authorizations are issued by
A) a Responsible Person designated by the Building Owner.
B) a Building Department inspector.
C) a FDNY inspector.
D) the Building owner's insurance company. - ANSWER-A) a
Responsible Person designated by the building owner.
Insecticidal fogging operations are hazardous because chemicals
A) are corrosive.
B) are water-reactive.
C) may be toxic.
D) are highly unstable. - ANSWER-C) may be toxic.
What is a compressor safety head?
A) Rupture disc.
B) A pressure relief valve on the low side.
C) Cylinder head with a low pressure relief on the high side.
D) A spring on the valve plate. - ANSWER-
The oil collected in an oil separator is generally
, A) caused by an oil overcharge.
B) returned to the compressor.
C) filtered and returned to the compressor.
D) drained and replaced by fresh oil. - ANSWER-
Where is emergency power not required according to code?
A) Fire pumps.
B) High rise elevators.
C) Egress illumination.
D) Data centers. - ANSWER-D) Data centers.
Modern compressors usually seal the rotating shaft seal as it exits the
compressor housing a spring-loaded seal made of
A) low-friction plastic.
B) rubber.
C) metal or carbon.
D) graphite-loaded fiber. - ANSWER-
A technician shows up to service the fire alarm panel in your building.
What COF qualifications must he/she have?
A) A Q-01/Q-99 Certificate of Qualification holder who is designated
by the building owner.
2026) UPDATE!! (Recent exam) Merged
With Correct Complete Solutions
Already Graded A+ || 2026-2027 Latest
Update!!!
In a steam turbine, what is the function of a Kingsbury thrust bearing?
A) Maintain first stage steam pressure.
B) Compensate for coupling misalignment.
C) Adjust shaft torque at start up.
D) Maintain axial positioning of the rotor shaft. - ANSWER-D) Maintain
axial positioning of the rotor shaft.
The ratio of actual pressure of water pressure in the atmosphere to
the saturated pressure of given temperature is
,A) partial pressure.
B) relative humidity.
C) humidity effect.
D) absolute humidity. - ANSWER-
The total amount of heat to be removed from the refrigerant in a
condenser equals the heat picked up in the
A) evaporator plus the heat of compression.
B) evaporator.
C) evaporator plus the heat of included non-condensable.
D) evaporator less the heat given up in the muffler. - ANSWER-
When must the Fire Department be notified that a fire protection
system is out of service?
A) The manual pull alarm station in the lobby will be out of service for
4 hours.
B) Four sprinkler heads on a same floor of your building will be out of
service for 2 hours.
C) The sprinkler system will be out of service on 1st and 2nd floors.
D) The fire alarm system is out of service in the refrigerating system
room for g hours. - ANSWER-C) The sprinkler system will be out of
service on 1st and 2nd floors.
,Hot work authorizations are issued by
A) a Responsible Person designated by the Building Owner.
B) a Building Department inspector.
C) a FDNY inspector.
D) the Building owner's insurance company. - ANSWER-A) a
Responsible Person designated by the building owner.
Insecticidal fogging operations are hazardous because chemicals
A) are corrosive.
B) are water-reactive.
C) may be toxic.
D) are highly unstable. - ANSWER-C) may be toxic.
What is a compressor safety head?
A) Rupture disc.
B) A pressure relief valve on the low side.
C) Cylinder head with a low pressure relief on the high side.
D) A spring on the valve plate. - ANSWER-
The oil collected in an oil separator is generally
, A) caused by an oil overcharge.
B) returned to the compressor.
C) filtered and returned to the compressor.
D) drained and replaced by fresh oil. - ANSWER-
Where is emergency power not required according to code?
A) Fire pumps.
B) High rise elevators.
C) Egress illumination.
D) Data centers. - ANSWER-D) Data centers.
Modern compressors usually seal the rotating shaft seal as it exits the
compressor housing a spring-loaded seal made of
A) low-friction plastic.
B) rubber.
C) metal or carbon.
D) graphite-loaded fiber. - ANSWER-
A technician shows up to service the fire alarm panel in your building.
What COF qualifications must he/she have?
A) A Q-01/Q-99 Certificate of Qualification holder who is designated
by the building owner.
