Type III — Low-PressureQuestion 164 of 240
What is the primary purpose of a purge unit on a low-pressure centrifugal chiller?
a.To add refrigerant to the system
b.To lubricate the compressor bearings
c.To circulate chilled water
d.To remove non-condensable gases such as air
Explanation
A purge unit removes non-condensable gases, mainly air and moisture, that leak into a chiller running under vacuum and collect at the top of the condenser. Removing them lowers head pressure and restores efficiency. A high-efficiency purge unit also recovers refrigerant vapor before venting the air.
Practice all 240 questions free — no signup required.
Related questions on this topic
- A technician is recovering R-11 from a low-pressure centrifugal chiller for a tear-down. To what evacuation level must the appliance be recovered?
- When pressurizing a low-pressure appliance to search for leaks, what is the maximum pressure a technician may apply?
- The rupture disk on a low-pressure chiller is a safety device that is typically designed to relieve at what pressure?
- Which of the following is a low-pressure refrigerant used in centrifugal chillers?
- Because a low-pressure chiller operates in a vacuum on the low side, what happens when it develops a leak?
- Water entering the refrigerant side of a low-pressure chiller through a leaking tube is dangerous mainly because it can:
Last reviewed: · editorial process
PrepPass Editorial Team · Verified against EPA Section 608 Technician Certification Exam · How we review