Abstract: A storage-type water heater including a tank for supporting water to be heated, a first heating element, a first relay connected to the first heating element, a second heating element, a second relay connected to the second heating element, and a controller for selectively operating the first relay and the second relay. The controller includes instructions for selecting a mode from at least, a no-sequencing mode, wherein the first relay and the second relay are operated concurrently, and a sequencing mode, wherein the first relay and the second relay are operated sequentially. The controller also operates the first relay to supply power to the first heating element, and operates the second relay to supply power to the second heating element, based on the selected mode.

Abstract: A storage-type water heater includes a tank for supporting water to be heated, a first heating bank including a first heating surface disposed within the tank, a first contactor connected to the first heating bank, a second heating bank including a second heating surface disposed within the tank, a second contactor connected to the second heating bank, and a controller for selectively operating the first contactor and the second contactor.

Abstract: A secondary safety circuit for a gas-fired device and method of operating the circuit. The secondary safety circuit includes a low-voltage direct current power source, a valve, and at least one sensor. The valve can be positioned in a pilot burner gas line. The secondary safety circuit ensures the valve is closed upon detecting an unsafe condition with the sensor.

Abstract: A storage-type water heater. The storage-type water heater comprising a water storage tank configured to retain tank water, means for heating the tank water in the water storage tank, and an anti-stacking pump assembly. The anti-stacking pump assembly includes a water tube configured to be positioned in the water storage tank, an impeller positioned within the water tube, a motor drivingly connected to the impeller, a water inlet formed in the water tube upstream of the impeller and configured to deliver tank water into the water tube from the water storage tank, and a water outlet formed in the water tube downstream of the impeller.

Abstract: A burner tube and door assembly for a water heater includes a burner tube and a fuel supply line in telescoping relationship to define a tube junction. The tube junction extends through the door of a water heater. One of the tube and line includes an enlarged portion. A lock ring applies a radially-directed force around a portion of the tube junction. The enlarged portion and lock ring are on opposite sides of the door to secure the door to the burner tube and fuel supply line. The enlarged portion and lock ring apply a compressive load to the door to resist rotation of the door with respect to the tube junction.

Abstract: A gas water heater includes a power burner, a flue tube, an exhaust plenum, and a draft hood. The flue tube includes a portion that describes at least a 360° loop. Products of combustion are forced through the flue tube under the influence of the power burner, and enter the exhaust plenum. In the exhaust plenum, the pressure of the products of combustion drops such that the products of combustion flow into the draft hood substantially entirely under the influence of natural convection. In one embodiment, the power burner fires down into the flue tube through a side wall of the water heater, the loop of the flue tube is near the bottom of the water heater, and the plenum is in the top of the water heater.

Abstract: Water tanks, such as water heaters, are coated with an organic polymer coating, which coating contacts water during use of the water tank. The organic polymer coatings resist corrosion or blistering when used to store or contain water. The water tanks may be made by treating a metal surface prior to application of the organic polymer coating.

Abstract: A temperature adjustable water mixing valve having a cold water inlet, a cold water outlet, a hot water inlet, a mixing water outlet, and a valve core configured to open or close water channels. The temperature adjustable water mixing valve further includes a pressure relief channel between the cold water inlet and a port connected with a water storage device. The channel is equipped with a check valve allowing water to flow from the water storage device to the cold water inlet. The temperature adjustable water mixing valve opens the check valve to discharge toward the front-end water source when the inner pressure in the water storage device is high.

Abstract: A storage-type water heater includes a tank enclosing a volume of water, the tank having an upper portion and a lower portion, a chamber adjacent the lower portion of the tank and adapted to at least partially enclose a source of a heated fluid, and a helical tube heat exchanger at least partially enclosed within the tank and fluidly connected to the chamber. The helical tube directs the heated fluid from the lower portion to the upper portion of the tank and promotes heat exchange between the water in the tank and the heated fluid flowing therethrough.

Abstract: A dry-fire protection system and method. The dry-fire protection system includes a tank, a heating element, a powered electrode, a sensor, and a microcircuit. The heating element and the powered electrode are positioned in the tank, the powered electrode being positioned above the heating element. The powered electrode includes an electrode wire and a connector having an electrical connector coupled to the electrode wire, but electrically isolated from the tank, and a fastener for coupling the powered electrode to the tank. The sensor detects an electrical characteristic of a circuit formed by the tank, the powered electrode, and water in the tank. The microcircuit determines if a possible dry-fire condition exists based on a signal received from the sensor.

Abstract: A water heater. The water heater includes a water tank adapted to contain water to be heated, a combustion chamber positioned proximate the water tank, a combustor positioned in the combustion chamber and operable to create products of combustion, a passage extending upwardly from the combustion chamber and through the water tank, the passage having an upper portion comprising an inner tube and an outer tube and a lower portion comprising an inner tube and an outer tube, and a transition element positioned in the passage and configured to direct supply air from the outer tube of the upper portion to the inner tube of the lower portion and deliver hot products of combustion from the outer tube of the lower portion to the inner tube of the upper portion, the transition element maintaining separation of the supply air and the products of combustion.

Abstract: A water heater including a water inlet line having an inlet opening that introduces cold water to a tank, a water outlet line having an outlet opening that withdraws heated water from the tank, and a heating element. The water heater further includes a control circuit. The heating element can be an electrical resistance heating element, a gas heating element, or a combination thereof. In one construction, the gas heating element includes a first combustive section and a second combustive section separately controlled from the first combustive section.

Abstract: Methods and systems for evaluating the condition of a water tank having a powered anode protection system. The water heater includes a storage tank to hold water, a powered anode, and a control circuit. The control circuit includes a variable voltage supply, a voltage sensor, and a current sensor. The control circuit is configured to compare a measured parameter to a threshold. In some constructions, the threshold is indicative of a condition of the storage tank at which the powered anode is no longer able to protect the storage tank from corrosion. In other constructions, the threshold is predicative of a potential failure of the storage tank caused by corrosion. In some constructions, the control circuit is configured to estimate a time remaining until the predicted failure of the storage tank.

Abstract: A gas water heater with a warning function, the gas water heater being disposed in a facility and comprising: a gas water heater main body including a controller having a warning cell; and a gas detecting unit separate from the main body and disposed at an indoor monitoring point of the facility, the gas detecting unit having a gas sensor and being in communication with the controller.

Abstract: A water heater. The water heater includes a water tank having a tank wall defining an interior space and adapted to contain water to be heated, a tank extension having an extension wall detachably mounted to the tank wall, the extension wall defining extension space communicating with the interior space, and defining an extension axis, an air inlet at least partially in the extension space extending through the extension wall at a radial angle to extension axis of tank extension, a combustor at least partially in the extension space and in fluid communication with the air inlet, and a plurality of heat exchange tubes configured to receive products of combustion from combustor and extending into interior space of the water tank. The extension space is configured to be flooded with water from the water tank.

Abstract: A sacrificial anode assembly. The sacrificial anode assembly includes a sacrificial anode, an insulator positioned around an end of the anode, an electric coupler positioned around the insulator and extending beyond the end of the anode, the electric coupler electrically isolated from the anode, a resistor having a first lead and a second lead, the first lead electrically connected to the anode and the second lead electrically connected to the electric coupler, and a cap positioned around the electric coupler, the cap electrically connected to the electric coupler and electrically isolated from the anode. The cap complete encapsulates the resistor, the first lead, and the second lead.

Abstract: A method of manufacturing a water heater includes the steps of providing a water heater tank having an interior and an exterior, the tank also including a first aperture communicating between the interior and exterior, providing a spud having an internally threaded aperture and placing a membrane between the spud and the tank such that the membrane covers the first aperture. Thereafter, the method also includes the steps of welding the spud and the membrane to the tank, and thereafter forming a second aperture in the membrane so that the threaded aperture of the spud communicates with the interior of the tank via the first and second apertures.

Abstract: A fluid-heating apparatus for heating a fluid and method of operating the same. The fluid-heating apparatus includes a heating element for heating a fluid surrounding the heating element and a control circuit connected to the heating element and connectable to a power source. The control circuit is configured to determine whether a potential dry-fire condition exists for the heating element. In one implementation, the method includes applying a first electric signal to the heating element, detecting a first value of an electrical characteristic during the application of the first electric signal, applying a second electric signal to the heating element, applying a third electric signal to the heating element, detecting a second value of the electrical characteristic during the application of the third electric signal; and determining whether a potential dry-fire condition exists based on the first and second values.

Abstract: A method of storing water at two temperatures, the method comprising: providing a tank divided into first and second chambers; storing water in the first chamber at a first temperature; storing water in the second chamber at a second temperature; heating water in the second chamber when the second temperature is below a predetermined second value; pumping water from the second chamber to the first chamber when the first temperature is below a predetermined first value, the first values being less than the second value; and permitting water flow from the first chamber to the second chamber while pumping water from the second chamber to the first chamber.