Type III — Low-Pressure第 194 / 240 题
Which of the following is NOT a low-pressure appliance refrigerant?
a.CFC-11
b.HFC-404A
c.HCFC-123
d.R-1233zd
解析
HFC-404A is a high-pressure blend used in commercial refrigeration, not a low-pressure chiller refrigerant. CFC-11, HCFC-123, and R-1233zd are all low-pressure refrigerants that run in a vacuum. Sorting refrigerants by pressure class is a common exam task.
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同考点相关题目
- The main reason a torch must never be used to warm a low-pressure chiller during recovery is that:
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- Excessive water in a low-pressure chiller can freeze and rupture tubes because low-pressure refrigerants:
- When handling a large recovery cylinder of R-11 removed from a chiller, the technician must remember to:
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