Patent ID: 8887672

Claim:
An appliance comprising: a water heater storage tank; a heating assembly configured to heat water within the water heater storage tank; and a heat exchange device disposed within the water heater storage tank in a fixed relationship relative to a position of the heating assembly, the heat exchange device comprising: a plurality of individual containment devices disposed in an array; wherein each of the plurality of individual containment devices comprises: a hollow ring member; and a plurality of hollow cross-members disposed within a central opening of the hollow ring member, and wherein one hollow ring member is disposed adjacent another hollow ring member to form the array; a phase change material retained within each of the plurality of individual containment devices; and a fluid path over and around each of the plurality of individual containment devices, wherein the water in the water heater storage tank is configured to flow in the fluid path over and around each of the plurality of individual containment devices to exchange heat directly from each of the plurality of individual containment devices prior to being discharged from the water heater storage tank.