In a hydrant assembly, the combination comprising an outer tubular member having a first flow port.; an inner tubular member having a closure thereon to close the port in relatively axially advanced position of the closure, and to open the port in relatively axially retracted position of the closure that allows fluid flow through the port to an outlet, control means to control relative movement of the inner and outer members. A second port may be located sidewardly of the outer tubular member to pass fluid in relatively retracted position of the closure to relieve fluid pressure in space formed between the inner and outer members, the inner member being elongated and extending lengthwise in the outer tubular member. The outer tubular member may consist of plastic material. Travel of the closure acts to allow expansion of fluid as it freezes, to relieve pressure build-up within the assembly.