Generally speaking, it is a drainage pipe. These two drainage pipes are used to switch directions. The small thin plastic pipe behind the automatic washing machine is used to transmit high and low water level signals. One end is connected to the air chamber interface of the washing machine barrel, and the other end is connected to the water level setting switch interface at the upper part of the washing machine.

When the automatic water injection of the washing machine reaches the set water level, the increase of air pressure in the air chamber is transmitted to the water level switch through this pipeline, and the water level switch sends a signal to cut off the power supply of the water intake solenoid valve to stop water injection, and at the same time, the motor is started to start the washing program. This pipe is generally a 6X4 plastic pipe, and both ends are bonded and fixed by clamps.