Drain pipe for building air conditioner

The utility model discloses a drainage pipe for a building air conditioner, which comprises a drainage pipe main body, fixed mounting rings, a first connecting port, a one-way valve and a second connecting port, and two groups of fixed mounting rings at equal intervals are fixedly mounted on the surface of the drainage pipe main body. The one-way valve is arranged and has an anti-backflow function, when a water source of the air conditioner flows out, the pressure of the side A is higher than that of the side B, the steel ball moves leftwards, the water source flows from the side A to the sideB, and the one-way valve is in an open state; when an external water source reversely flows in, water flows out; the B-side pressure is higher than the A-side pressure; right movement of steel ball,blocked refrigerant circulation line, according to the drainage pipe for the building air conditioner, the arc-shaped net plate is arranged, the arc-shaped net plate does not influence normal flowingof a water source, meanwhil