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Practice the FDNY refrigeration practical in a 3D chiller plant
A free simulator for the Z-52 RSOE practical exam, the hands-on part of the NYC Q-01 Refrigerating System Operating Engineer license. Walk a full machine room, open and close every valve, run startup and shutdown step by step, chase down faults and sit a timed practice exam on both systems.
Works on computers, tablets and phones. Best on a computer or tablet.
Click to open the plant
Which exam is this for?
New York City requires a Certificate of Qualification (Q-01) for Refrigerating System Operating Engineer (RSOE) to operate and supervise refrigerating systems that need an FDNY permit. Getting it takes two FDNY exams:
- Z-51, the written computer exam (RSOE Exam Part I, fundamentals).
- Z-52, the practical exam (RSOE Exam Part II), taken on a 3D computer model of a centrifugal and a reciprocating refrigeration system. Passing it earns the Q-99 letter you use to get your Q-01 card.
You may hear it called the NYC refrigeration license, the refrigeration engineer license, the refrigeration machine operator license, the Q-01 or the RSOE. They all point to the same FDNY certificate, and this trainer is built for its practical exam. See the full step-by-step license guide.
What you can practice
The Z-52 practical tests operations, validation of repairs and maintenance, refrigerant handling, troubleshooting, multi-step tasks and scenarios on both machines. The trainer lets you rehearse all of it.
Startup and shutdown
Follow each procedure step by step, or press Watch and let it run and narrate itself while the camera flies to every valve and gauge.
Find every part
Hundreds of clickable valves, gauges, sight glasses, switches and transducers, each with its normal position, live reading and what it does.
Troubleshooting drills
Faults hidden in the plant: read the symptoms, find the cause, make the repair and put the machine back in service.
Timed practice exam
Like the real exam you finish one system, then the other, and cannot go back. Tasks in the plant, identification and multiple-choice questions, scored at the end.
Reference documents
Pressure-temperature (PT) chart, safety data sheets, chiller spec sheets and the RSR operating diagram, open beside the plant just like at the exam.
Voice narration
Turn on the voice and the trainer reads each step, lesson and part out loud, so you can listen while you look around.
Two machines, one plant
The practical covers a centrifugal and a reciprocating system. Both chillers here share the chilled-water loop, the condenser-water loop, the pumps and the cooling tower, so you learn how the whole plant works together.
Steam-turbine-driven centrifugal
- Steam turbine with governor, overspeed trip and gland seals
- Surface condenser, hotwell, condensate and vacuum pumps
- Compressor and turbine oil systems, purge unit
- Steam traps, drip leg and condensate tank
- Refrigerant recovery with the storage and recovery (RSR) unit
Water-cooled reciprocating
- Two refrigerant systems with semi-hermetic compressors
- Service valves, king valves, filter-driers and sight glasses
- Liquid-line solenoids and thermostatic expansion valves
- Cylinder unloaders, oil sight glasses and crankcase heaters
- High- and low-pressure cutouts and oil safety switches
Water side and safety
- Chilled-water and condenser-water pumps with hand-off-auto switches and lockout
- Cooling tower with fan, belt drive, fill and make-up water
- Air handler, expansion tank and make-up system
- Strainers, check valves, flow switches and water gauges
- Refrigerant detector, emergency stop and relief piping
Study guides
Plain-language guides that go with the trainer.
The Z-52 RSOE practical exam
How the simulator exam is laid out, the six question categories, the reference documents and how to prepare.
Read the guide →How to get the NYC Q-01 license
Eligibility, the Z-51 written and Z-52 practical exams, the Q-99 letter, the Q-01 card and renewal.
Read the guide →Chiller startup and shutdown procedures
Every step of the trainer's centrifugal and reciprocating startup, shutdown, pump-down and refrigerant recovery procedures.
See the procedures →Questions
Is the trainer free?
Yes. It runs in your web browser with no sign-up, no download and no payment.
Which exam is this for?
The FDNY Q-01 Certificate of Qualification for Refrigerating System Operating Engineer (RSOE) in New York City. The trainer is built for the practical part, the Z-52 RSOE Practical exam (now also called RSOE Exam Part II), which is taken on a 3D computer simulation of a centrifugal and a reciprocating refrigeration system.
Is this the same as the refrigeration machine operator license?
Many people still call the NYC refrigeration license the refrigeration machine operator license, the refrigeration engineer license or the Q-01 license. The current FDNY name is the Q-01 Certificate of Qualification for Refrigerating System Operating Engineer (RSOE).
Is this an official FDNY site?
No. Refrigeration Practical is an independent study aid. It is not affiliated with, endorsed by or connected to the FDNY or the City of New York. Always study the official FDNY notice of examination and study materials.
What does the trainer cover?
Two chiller plants: CH-1, a 500-ton steam-turbine-driven centrifugal on R-134a with its surface condenser, vacuum and condensate pumps, and CH-3, a 150-ton two-system reciprocating chiller on R-22. You can practice startup, shutdown and refrigerant recovery procedures, identify valves and gauges, troubleshoot faults and take a timed practice exam.
Does it work on a phone?
Yes. It works on phones, tablets and computers. A computer or tablet gives the best view of the 3D plant.