RefrigerationCâu 64 / 110
Evacuating a system with a vacuum pump primarily removes what?
a.Refrigerant oil
b.Copper scale
c.Moisture and non-condensable gases such as air
d.The compressor windings
Giải thích
A deep vacuum boils off moisture and pulls out air and other non-condensables that would otherwise raise head pressure, form acids, or cause icing at the metering device. A micron gauge verifies the target vacuum is reached and held. Proper evacuation is essential before charging.
Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- On a fixed-orifice (piston) system, which method is generally used to check the charge?
- Under EPA Section 608, what must a technician do with refrigerant before opening most systems for service?
- EPA Section 608 certification is required for technicians who do what?
- A micron gauge is used during evacuation to measure what?
- Which instrument or method is commonly used for pinpointing small refrigerant leaks?
- As a general principle, adding refrigerant charge to a properly running system tends to do what to the low-side pressure?
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