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
解析
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.
法律依据: 40 CFR §82.152免费刷完整 240 道题库 — 无需注册。
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同考点相关题目
- When pressurizing a low-pressure appliance to search for leaks, what is the maximum pressure a technician may apply?
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- Because a low-pressure chiller operates in a vacuum on the low side, what happens when it develops a leak?
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