对于KFR型空调器，若制冷正常，而不制热，其故障主要发生在四通电磁阀或其控制电路。

For KFR type air-conditioner, if refrigeration normal, not heating, its fault mainly in four electromagnetic valve or its control circuit.

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其中大四通和双管结构是组成采油树的主要部件，也是整个装置的主要承压部件。

And the big tubing cross and the double barrel structures are compose the production tree the major component, is also the entire installment main bearing pressure part.

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直通式旋塞阀主要做切断用，三通式和四通式用于分配用于分配介质流量。

Straight-through processing Xuan Sefa mainly used to do cut off, three-and four-way-to medium allocated for the distribution of traffic.

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