Abstract: A hydrant comprising a housing forming a reservoir; and a piston configured to force residual fluid out of the reservoir to an outlet and to allow supply fluid to flow from an inlet through the piston to the outlet when the piston is actuated in the housing to a first position, and when the piston is actuated in the housing to a second position, to restrict flow of the supply fluid to the outlet and to allow at least a portion of the supply fluid that has flowed from the inlet to flow into the reservoir thereby becoming new residual fluid.

Abstract: A hydrant comprising a chamber forming a reservoir, an inlet configured to supply fluid to the hydrant and a sleeve configured to force static fluid out of an outlet, wherein a first portion of the chamber containing the reservoir is configured to be located in the ground below a frost line and a second portion of the chamber is configured to be located above the frost line, wherein the static fluid is forced to exit the outlet above the ground and residual fluid is trapped in the reservoir inhibiting freezing when the sleeve moves to a first position, and when in a second position the sleeve is configured to allow supply fluid to exit the outlet through the reservoir, thereby purging the reservoir of residual fluid.