FDNY Z51 ACTUAL EXAM WITH 150

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FDNY Z51 ACTUAL EXAM WITH 150

QUESTIONS AND CORRECT ANSWERS (100%

CORRECT VERIFIED ANSWERS) ACTUAL FDNY

Z-51 WRITTEN EXAM (BRAND NEW!!)

A technician shows up to service the fire alarm panel in your building. What COF qualifications must he/she have?

• A Q-01/Q-99 Certificate of Qualification holder who is designated by the

building owner.

• A certified Fire Safety Director who is designated by the building owner.
• A S-95 Certificate of Fitness holder who is employed by a FDNY certified

company.

• A S-97/S-98 Certificate of Fitness holder who is employed by a FDNY certified

company. - ANSWER-D) A S-97/S-98 Certificate of Fitness holder who is employed by a FDNY certified company.

When must the Fire Department be notified that a fire protection system is out of service?

• The manual pull alarm station in the lobby will be out of service for 4 hours.
• Four sprinkler heads on a same floor of your building will be out of service for
• hours.
• The sprinkler system will be out of service on 1st and 2nd floors.
• 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.

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pg. 2 Hot work authorizations are issued by

• a Responsible Person designated by the Building Owner.
• a Building Department inspector.
• a FDNY inspector.
• the Building owner's insurance company. - ANSWER-A) a Responsible Person

designated by the building owner.

Insecticidal fogging operations are hazardous because chemicals

• are corrosive.
• are water-reactive.
• may be toxic.
• are highly unstable. - ANSWER-C) may be toxic.

In a steam turbine, what is the function of a Kingsbury thrust bearing?

• Maintain first stage steam pressure.
• Compensate for coupling misalignment.
• Adjust shaft torque at start up.
• Maintain axial positioning of the rotor shaft. - ANSWER-D) Maintain axial

positioning of the rotor shaft.

What is the lowest temperature the water in the cooling tower can be?

• Ambient. 2 / 4

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• Between wet and dry bulb.
• Dry bulb.
• Wet bulb. - ANSWER-B) Between wet and dry bulb.

The most important reason to subcool the refrigerant in the condenser is to ensure that

• liquid slugs will not enter the compressor.
• the cooling tower has sufficient water.
• the condenser is working efficiently.
• a pure liquid refrigerant will enter the metering device. - ANSWER-D) a pure

liquid refrigerant will enter the metering device.

A chilled water system that has an air cooled condensing unit on a roof during cold weather has what type of protection?

• Glycol running through it.
• Air-limiting device.
• Heater coil.
• Resistor. - ANSWER-B) Air-limiting device.

An engineer observes a gauge that reads saturation pressure of a refrigerant. If chilled water is circulated as the cooling medium, this reading can best be used to estimate the

• chilled water return from building spaces being pumped to the spaces being

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• cooling tower efficiency.
• pressure of chilled water being pumped to spaces being cooled.
• temperature of chilled water being pumped to the spaces being cooled. -

ANSWER-D) temperature of chilled water being pumped to the spaces being cooled.

The purpose of wear rings in a centrifugal pump is to

• act as a bearing to reduce axial motion after wear occurs.
• prevent wearing of the pump housing and impeller.
• center the impeller in the pump casing.
• minimize water leakage around the shaft. - ANSWER-B) prevent wearing of

the pump housing and impeller.

Of the follow, an example of an in-line refrigerant cleaning system that may be

used with a centrifugal compressor containing R123 refrigerant is:

• Refrigerant reclaiming.
• Refrigerant disposal.
• Refrigerant recycling.
• Refrigerant recovery. - ANSWER-C) Refrigerant recycling.

Refrigerating system refrigerant detection systems must be tested at least

• annually.
• monthly.
• daily.
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