China factory price SMOOTH AND INNER GROOVED Copper tube and copper fitting

The function is to connect the internal and external machines, so that the inner and outer machines form a closed system. The refrigerant can circulate in the inner and outer machines. Under normal circumstances, the large pipe takes the gaseous refrigerant and the small pipe goes. The liquid is too cold. As for which one to enter and which one to go out, it depends on the cooling and heating modes of the air conditioner. In the heating mode, the refrigerant enters the internal machine through the large pipe from the external machine, and returns to the external machine through the small pipe. In the cooling mode, the refrigerant enters the internal machine through the small pipe from the external machine, and returns to the external machine through the large pipe.