Which of the following is a low-pressure refrigerant used in centrifugal chillers?
a.HCFC-123
b.HCFC-22
c.HFC-404A
d.HFC-410A
Giải thích
HCFC-123 is a classic low-pressure chiller refrigerant, along with CFC-11 and the newer R-1233zd. 40 CFR §82.152 defines a low-pressure appliance as one whose refrigerant has a liquid-phase saturation pressure below 45 psia at 104°F, which is why these machines run in a vacuum on the low side. R-22, R-404A and R-410A are high-pressure refrigerants (170–355 psia at 104°F) and fall under Type II.
Trích dẫn luật: 40 CFR §82.152Luyện miễn phí toàn bộ 240 câu hỏi — không cần đăng ký.
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Câu hỏi liên quan cùng chủ đề
- 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?
- What is the primary purpose of a purge unit on a low-pressure centrifugal chiller?
- 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:
- To speed up refrigerant recovery from a low-pressure chiller, a technician should:
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