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單項(xiàng)選擇題

If you find an extremely large refrigerant leak while using a halide torch, your flame will（）

A.change from blue to orange
B.‘flare up’ and remain lighted
C.probably go out
D.stay blue

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單項(xiàng)選擇題

Before charging a refrigeration unit, the refrigerant charging lines should be（）

A.flushed with clean refrigerant oil
B.purged with the refrigerant
C.washed with an ammonia and alcohol solution
D.grounded to compressor

單項(xiàng)選擇題

In the presence of an open flame or hot surfaces, chlorinated fluorocarbon refrigerants decomposes and from （）.

A.petroleum crystals
B.phosgene gas
C.water vapor
D.carbon monoxide

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