Type III — Low-Pressure第 198 / 240 题
The deep 25 mm Hg absolute recovery requirement exists for low-pressure appliances because:
a.Their charge is very small
b.Their refrigerant boils near room temperature and must be pulled out thoroughly under deep vacuum
c.They contain no oil
d.They operate above atmospheric pressure
解析
Low-pressure refrigerant boils near room temperature, so recovering it fully requires pulling the appliance down to a deep vacuum of 25 mm Hg absolute to draw out the remaining vapor. Shallow vacuums would leave significant refrigerant behind. The deep level ensures thorough recovery from these vacuum-operating machines.
法律依据: 40 CFR §82.156免费刷完整 240 道题库 — 无需注册。
同考点相关题目
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