Multi-tank storage type gas water heater

A storage type gas water heater comprising:

• a housing defining a base and a top;
• a primary water storage area within the housing;
• a gas combustion chamber within the housing and situated vertically below the primary water storage area and above the base;
• a gas burner situated in the gas combustion chamber;
• a gas inlet in communication with the gas burner for providing gas to the gas burner;
• an energy recovery chamber within the housing and situated vertically above the primary water storage area, the energy recovery chamber defined by a lower partition and an upper partition;
• a supplementary water storage area within the housing and situated vertically above the upper partition of the energy recovery chamber, the supplementary water storage area having a supplementary water storage area water outlet;
• a cold water inlet extending into the housing and in communication with the supplementary water storage area for supplying external cold water to the supplementary water storage area;
• a water heat exchanger situated in the energy recovery chamber, the water heat exchanger having a water heat exchanger water outlet, and a water heat exchanger water inlet in communication with the supplementary water storage area water outlet for receiving cold water from the supplementary water storage area, wherein the water heat exchanger comprises a tubular water heat exchanger situated about an external wall of the energy recovery chamber;
• a first flue portion extending vertically from the gas combustion chamber, through the primary water storage area, the lower partition of the energy recovery chamber, and into the energy recovery chamber for directing combustion gas from the gas combustion chamber into the energy recovery chamber and allowing the combustion gas to impinge on the water heat exchanger to temperate the cold water in the water heat exchanger received from the supplementary water storage area;
• a primary water storage area inlet in communication with the water heat exchanger water outlet for receiving temperate water from the water heat exchanger into the primary water storage area;
• a primary water storage area outlet extending from the primary water storage area to outside the housing;
• and
• a second gas flue portion extending vertically from the upper partition of the energy recovery chamber vertically above the water heat exchanger, through the supplementary water storage area, and external of the housing;
• the gas burner configured to heat the received temperate water from the supplementary water storage area to a preset temperature via the gas burner situated in the gas combustion chamber for outputting heated water from the primary water area and external of the housing via the primary water storage area outlet;
• a second energy recovery chamber within the housing and situated vertically above the supplementary water storage area, the second energy recovery chamber defined by a second lower partition and a second upper partition;
• a second water heat exchanger situated in the second energy recovery chamber and vertically above the second flue portion and having a second water heat exchanger water inlet and a second water heat exchanger water outlet;
• a second supplementary water storage area situated in the housing vertically above the second energy recovery chamber and having a second supplementary water area inlet and a second supplementary water area outlet;
• the second flue portion situated entirely within the housing and extending through the supplementary water storage area and into the second energy recovery chamber for directing combustion gas from the energy recovery chamber into the second energy recovery chamber and allowing the combustion gas to impinge on the second water heat exchanger to heat the second water heat exchanger and temperate the water in the second water heat exchanger;
• a third flue portion extending vertically from the second energy recovery chamber vertically above the second water heat exchanger, through the second supplementary water storage area and out the housing;
• wherein the cold water inlet is coupled to the second supplementary water storage tank inlet for supplying cold water to the second supplementary water storage tank, the second supplementary water tank outlet is coupled to the second heat exchanger water tank inlet for supplying second temperate water from the second supplementary water storage area to the second water heat exchanger, and the second water heat exchanger water outlet is coupled to the supplementary water storage area water inlet for supplying temperate water from the second water heat exchanger to the supplementary water storage area.