Water heater or boiler with improved tank design

A water heater including a tank having external and internal sidewalls and an end opening, the internal sidewalls defining an open interior normally containing water under pressure, the improvement comprising:

• a submergible, pressurized combustion chamber having multiple external heating surfaces, said combustion chamber being insertible through the end opening into the open interior whereby all of the external heating surfaces are submerged in the water under pressure;
• combustion means for supplying the products of combustion to the submergible, pressurized combustion chamber;
• resilient sealing means carried by the submergible, pressurized combustion chamber for forming a sliding seal with the tank internal sidewalls as the combustion chamber is inserted within the tank interior, whereby the initially open interior of the tank is divided into a primary and secondary heat exchange compartments;
• a water inlet to the primary heat exchange compartment and a water outlet from the secondary heat exchange compartment;
• crossover means for allowing the controlled passage of water from the primary heat exchange compartment to the secondary heat exchange compartment.

A water heater of the type having a tank with a tank interior which defines a preheat or primary heat exchange compartment and a secondary heat exchange compartment, both compartments normally containing water under pressure, the water heater comprising:

• a submergible, pressurized combustion chamber with multiple external heating surfaces, said combustion chamber extending through an end opening of the water heater tank into an interior thereof so that all of the heating surfaces are submerged in the water under pressure;
• an air-fed, forced draft burner having a burner inlet and being mounted on the exterior of the water heater tank and communicating with the combustion chamber for causing combustion to take place within the submergible, pressurized combustion chamber so that substantially all combustion takes place in the tank interior to minimize heat loss;
• resilient sealing means carried by the submergible, pressurized combustion chamber for forming a sliding seal with the tank internal sidewalls as the combustion chamber is inserted within the tank interior, whereby the initially open interior of the tank is divided into the primary and secondary heat exchange compartments;
• a water inlet to the primary heat exchange compartment and a water outlet from the secondary heat exchange compartment;
• and
• crossover means for allowing the controlled passage of water from the preheat or primary heat exchange compartment to the secondary heat exchange compartment.

A combustion chamber assembly for use in a water heater of the type having a tank having external and internal sidewalls and an end opening, the internal sidewalls defining an open interior normally containing water under pressure, the combustion chamber assembly including:

• a combustion chamber body having multiple external heating surfaces, said combustion chamber body being insertible through the end opening into the open interior whereby all of the external heating surfaces are submerged in the water under pressure;
• resilient sealing means carried by the combustion chamber body for forming a sliding seal with the tank internal sidewalls when the combustion chamber is inserted within the tank interior, whereby the initially open interior of the tank is divided into a primary and secondary heat exchange compartments
• wherein the resilient sealing means includes a rigid divider plate carried by the combustion chamber body, the rigid divider plate having attached thereto a resilient wiper sealing surface for forming a sliding seal with the tank internal sidewalls as the combustion chamber body is inserted within the tank interior;
• and
• wherein a water inlet is connected to a selected one of the heat exchange compartments of the tank and a water outlet is connected to the other of the heat exchange compartments and wherein a crossover opening located in the rigid divider plate allows water to pass from one selected heat exchange compartment to the other within the tank interior.