Patent ID: 9255644
Filing Date: 2016-02-09
CPC Classification: F16K,F24D

Claim Text:
1. A natural resource conserving prompt hot water system comprising: a hot water tank including a tank body a tank top end, and a tank bottom end; a water inlet opening in the hot water tank connected to a water system supply pipe; a hot water discharge opening in the tank top end; a drain opening in the tank body adjacent to the tank bottom end; a hot water supply pipe with an inlet end connected to the hot water discharge opening in the hot water tank and extending away from the hot water tank to a supply pipe remote end; a plurality of point of use pipes each of which connects a hot water discharge faucet to the hot water supply pipe; a return pipe including a return pipe inlet end connected to the hot water supply pipe adjacent to the supply pipe remote end and with at least one of the plurality of point of use pipes between the return pipe connection to the hot water supply pipe and the hot water discharge opening in the tank top end, and a return pipe discharge end connected to the drain opening in the tank body, an inside diameter of the return and an inside diameter of the hot water supply pipe are substantially the same and wherein the increase in water density between cooled water high density at the return pipe discharge end and low density hot water at the hot water discharge opening in the hot water tank results in flow of low density hot water from the hot water tank and into the hot water supply pipe and flow of high density cool water from the return pipe and into the drain opening in the tank body thereby forming a pumpless circulation system that maintains hot water in the hot water supply pipe; a directional flow control device controlling the direction of flow through the return pipe end including a body, a conical bore portion in the body, an inlet end with an inlet bore that joins a small diameter end of the conical bore portion, a cylindrical bore portion in the body that joins a large diameter end of the conical bore portion, a plug having a plug tubular portion and an outlet bore through the plug tubular portion, a cylindrical plug portion received in the cylindrical bore portion and fixed to the body to form a chamber, an axis of the directional flow control device that is coaxial with the inlet bore, the conical bore portion, the cylindrical bore portion and the outlet bore through the plug and wherein the conical bore portion includes a conical wall surface that extends from the small diameter end to the large diameter end of the conical bore portion at an angle relative to the axis of more than 20 degrees; a nylon sphere positioned in the chamber of said directional control device movable by water flow in a first direction toward at least one projection in the chamber that limits movement of the nylon sphere toward the outlet bore and permits uninhibited water flow through the chamber, and movable by water flow in a second direction generally parallel to the axis and into the conical bore portion, in response to opening one of the hot water discharge faucets, and limiting flow of water through the inlet bore and into the hot water supply pipe; a fluid bypass between the nylon sphere and the conical bore portion that equalizes pressure to release the sphere upon closing of the hot water discharge faucets; and wherein the directional flow control device is between the return pipe inlet end and the drain opening in the tank body.