Two chillers in the same plant are both charged with R-123, one holding two hundred pounds and one holding two thousand pounds. How are the two machines classified?
Correct Answer
A) Both are low-pressure appliances because of the refrigerant they contain
Appliance class comes from the pressure behavior of the refrigerant in the machine, so two machines holding the same refrigerant land in the same class regardless of how much of it they hold. Both of these are low-pressure appliances requiring Type III certification. Charge size does matter elsewhere: it drives recordkeeping and leak repair obligations for the owner. But it never moves an appliance from one pressure category to another, and it never changes which certification the servicing technician must hold.
Why This Is the Correct Answer
R-123 sets the class for both machines. Because its boiling point at atmospheric pressure is above ordinary room temperature, any appliance charged with it operates partly in a vacuum and is a low-pressure appliance. Ten times the charge does not change the refrigerant's saturation pressure, so it cannot change the classification or the certification required.
Why the Other Options Are Wrong
Option B: The larger one is low-pressure and the smaller one is a high-pressure appliance
Nothing in the classification scheme splits machines by size. Two units with the same refrigerant sit in the same class whether one is a tenth the size of the other.
Option C: Both are high-pressure appliances because their charge exceeds fifty pounds
There is no fifty pound threshold that converts an appliance to high-pressure. Charge weight affects owner recordkeeping duties, not the pressure category.
Option D: The smaller one is treated as a small appliance and the larger one as low-pressure
Small appliance status requires a factory sealed system charged with five pounds or less. A two hundred pound field charged chiller is far outside that definition.
Memory Technique
Same juice, same class. Change the volume all you like, the refrigerant still decides.
Reference Hint
Pressure class depends on the refrigerant only; charge weight drives owner recordkeeping, not appliance classification.
More epa-608-type-3 Questions
Some jobs on a chiller count as a major repair under the refrigerant rules, which changes what a technician is allowed to do with a badly leaking machine. Which job falls into that category?
An owner asks how many pounds of refrigerant the rules allow to be left inside a chiller once the recovery has been signed off. What is the correct answer to give him?
The motor of a hermetic centrifugal chiller sits inside the pressure boundary rather than outside it on a shaft. What follows from that construction?
An oxygen monitor is used to decide whether a chiller machine room is safe to enter after a refrigerant release. Below what oxygen reading is the atmosphere treated as oxygen deficient?
A low-pressure chiller's rupture disc has a discharge line running from it. Where does that line have to terminate?
A refrigerant vapor detector in a chiller machine room reaches its alarm level. Besides sounding, what is that alarm expected to do?
Which piece of equipment requires a technician to hold Type III certification before it may be serviced?
What property of the refrigerant is what actually places an appliance into the low-pressure category?
During normal operation, what condition exists inside the evaporator of a running low-pressure centrifugal chiller?
In what unit is the required final recovery vacuum for a low-pressure appliance normally expressed?
People Also Study
Business & Financial Management
120 questions · 70% to pass
Contract Administration
60 questions · 70% to pass
Project Management
60 questions · 70% to pass
Related Study Resources
Previous Question
A laboratory has a small factory sealed packaged chiller holding four pounds of R-134a. Which certification covers service on that unit?
Next Question
During recovery from a centrifugal chiller the technician needs to know when the liquid phase has finished and the slow vapor phase is starting. What tells him that?