Water heater with passive automatic hot water circulation through a home or building

Abstract

A water heater unit is described for providing convective water flow through a water circulatory system. In one embodiment, the water heater unit has an outer housing, a water tank disposed within the housing, and a first cold water inlet coupled to the tank and connectable to a cold water supply line. A hot water outlet is coupled to the tank and connectable to a hot water supply line. A connection chamber adjacent to the tank has a second cold water inlet connectable to the cold water line, and a chamber outlet connected to the first cold water inlet of the tank. The connection chamber has at least one return inlet connectable to the hot water return line at a position to allow a substantially continuous flow of return hot water driven by convection forces without the benefit of a recirculation pump.

1 - 23 . (canceled) 
     
     
         24 . A continuous hot water supply system connectable to a water supply line and to a flow circuit having a hot water supply line, and a hot water return line connected to the hot water supply line, comprising:
 a water heating assembly coupled to the water supply line, wherein at least a portion of the water supply line extends from the water heating assembly;   a reservoir remote from the water heating assembly and positioned to receive heated water from the water heating assembly, the reservoir having a first inlet and a first outlet, the first outlet being connectable to the hot water supply line; and   a circulation device in fluid communication with the reservoir, the circulation device having a second inlet connectable to the water supply line to receive water therefrom, the circulation device having a second outlet in fluid connection with at least one of the water heating assembly and the reservoir, the circulation device having at least one return inlet connectable to the hot water return line and configured to allow a substantially continuous flow of return hot water therethrough driven by convection forces without the benefit of a recirculation pump, and a valve connected to the return inlet and being moveable between open and closed positions, the valve in the open position allowing recirculated hot water to flow into the chamber from the return line, and the valve in the closed position blocking water from flowing from the chamber through the return line.   
     
     
         25 . The continuous hot water supply system of  claim 24  wherein the water heating assembly is a tankless water heater. 
     
     
         26 . The continuous hot water supply system of  claim 24  wherein the reservoir includes a heating element activatable to heat water contained in the reservoir. 
     
     
         27 . The continuous hot water supply system of  claim 24  wherein the circulation device is positioned immediately adjacent to the reservoir. 
     
     
         28 . The continuous hot water supply system of  claim 24  wherein the circulation device is positioned immediately adjacent to and upstream from the water heating assembly. 
     
     
         29 . The continuous hot water supply system of  claim 24  wherein the second inlet of the circulation device is connected to the portion of the water supply line, and the second outlet of the circulation device is connected to the first inlet of the reservoir.