Abstract: A water heating apparatus including a tank divided into first and second chambers, wherein water in the first and second chambers has first and second temperatures, respectively, a first outlet for supplying water from the first chamber, a first thermostat to measure the first temperature, a second thermostat to measure the second temperature, means for heating water in the second chamber, a pump having a pump inlet in fluid communication with the second chamber and a pump outlet in fluid communication with the first chamber, and a controller configured to initiate pumping of water from the second chamber to the first chamber when the first temperature is below a predetermined first value. The controller is also configured to initiate heating of water in the second chamber when the second temperature is below a predetermined second value, the second value being greater than the first value.

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: A water heater for exchanging heat between hot gasses and water within the water heater. The water heater includes a water tank, a conduit for allowing flow of the gasses therethrough, the conduit extending through the tank and promoting heat exchange between the gasses and water in the tank, and a baffle extending within the conduit for affecting the flow of the gasses. The baffle includes a sheet bent in a zig-zag manner and having a number of plate sections. Each plate section has a through-flow portion allowing the gasses to flow therethrough. The sheet also has a number of first bends and a number of second bends, the first bends alternating with the second bends such that each plate section is defined between one first bend and one second bend.

Abstract: The invention includes a controller for a boiler and a method of detecting a short-cycling condition of the boiler. The controller includes a user interface module, a short-cycling detection module, and an adjustment module. The method includes the acts of detecting when the boiler is in a short-cycling condition and introducing delays at various operational points throughout a heating process.

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 dam assembly to protect a component mounted on a water heater tank wall while insulating foam is injected between the tank and a jacket surrounding the tank, the dam assembly comprising an outer portion, an inner portion, and a frangible web connecting the inner and outer portions, the web having a strength sufficient to withstand force applied to the inner portion to press the dam assembly into an aperture in the jacket such that the outer portion surrounds the component between the tank and the jacket, and the web breaking under the application of a pre-determined force on the inner portion, allowing the inner portion to be at least partially pushed inside the outer portion to enclose the component within the dam assembly.

Abstract: A water heater includes a sealed combustion chamber and one or more fans for raising pressure in the combustion chamber to increase efficiency of the water heater. The pressure permits a more restrictive baffle to be used in the flue compared to baffles used in atmospheric water heaters. The water heater may include a water temperature sensor that activates the fan without activating the burner if water temperature raises above a desired temperature. The water heater may also include pressure and vapor sensors to ensure the combustion chamber is properly sealed and there are no flammable vapors present prior to igniting the burner. The fans are relatively small and run off the same DC power that runs an electric gas valve. The fans may be, for example, 12 or 24 Volt fans with power inputs of about 10 Watts or less.

Abstract: A thermal cut-off circuit for a gas-fired device and method of operating the circuit. The thermal cut-off circuit includes a thermal cut-off switch and an ambient thermal switch. The thermal cut-off switch is positioned in a combustion chamber and the ambient thermal switch is preferably positioned in a flow of air entering the combustion chamber. The thermal cut-off circuit ensures a gas valve is closed upon detecting a possible incomplete combustion in the combustion chamber.

Abstract: A pump control system for controlling a fluid pump powered by an AC signal. The pump control system includes a signal phase detector coupled to the fluid pump to detect the AC signal supplied to the fluid pump and to generate phase signals indicating a phase parameter of the AC signal. The pump control system also includes a micro-controller to receive the phase signals and to generate a rectified output signal based on the phase signals, and a relay to control the power supplied to the fluid pump based on the output signal of the micro-controller.

Abstract: An original equipment manufacturer water heater including a water tank including an inlet and an outlet, means for heating water in the water tank, a base pan at least partially supporting the water tank such that water leaked from the water tank collects in the base pan, a valve closable to prevent water from entering the water tank through the inlet, and a sensor positioned in the base pan, the sensor configured to close the valve upon detecting water.

Abstract: A water-resistant porcelain enamel coating and method of making the same is provided. The porcelain enamel coating is prepared using a borosilicate glass frit, and mill additions of silica and a zirconia compound. The mixture is applied to a metal substrate and fired, resulting in a water-resistant coating that resists cracking and crazing. The coating is particularly useful in water heaters. In one embodiment, the coating comprises a fine zirconia compound having a median particle size of less than 10 microns.

Abstract: The invention includes an apparatus and method of determining the type of igniter for a burner at each stage of a boiler. The apparatus includes a controller operable to detect whether a first type of igniter or a second type of igniter is installed in the burner based on whether the first type of igniter or the second type of igniter transmits a response to the controller after receiving an activation signal from the controller.

Abstract: A water heater having a powered electrode and a method of controlling the water heater. The water heater includes a tank to hold water, a heating element, an electrode, 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 controllably apply a voltage to the electrode, determine the potential of the electrode relative to the tank with the voltage sensor when the voltage does not power the electrode, determine a current applied to the tank after the voltage powers the electrode, determine a conductivity state of the water in the tank based on the electrode potential and the current, and define the voltage applied to the powered electrode based on the conductivity state. The control circuit of the water heater can also determine whether the water heater is in a dry-fire state.

Abstract: A blower for a water heater having a flue defining a flue axis. The blower includes a housing at least partially defining a first chamber and a second chamber and having an inlet opening into the first chamber and an outlet communicating between the second chamber and atmosphere, the inlet being alignable with the flue, a ramp extending through the second chamber and having a surface, the surface being oriented at an acute angle with respect to the flue axis, and an impeller positioned in the second chamber and being operable to draw exhaust from the flue into the first chamber through the inlet and being operable to direct the exhaust through the second chamber and across the surface of the ramp, the surface of the ramp directing the exhaust through the outlet in a direction substantially parallel to the flue axis.

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: A dam assembly to protect a component mounted on a water heater tank wall while insulating foam is injected between the tank and a jacket surrounding the tank, the dam assembly comprising an outer portion, an inner portion, and a frangible web connecting the inner and outer portions, the web having a strength sufficient to withstand force applied to the inner portion to press the dam assembly into an aperture in the jacket such that the outer portion surrounds the component between the tank and the jacket, and the web breaking under the application of a pre-determined force on the inner portion, allowing the inner portion to be at least partially pushed inside the outer portion to enclose the component within the dam assembly.

Abstract: The invention includes an apparatus and method of determining the type of igniter for a burner at each stage of a boiler. The apparatus includes a controller operable to detect whether a first type of igniter or a second type of igniter is installed in the burner based on whether the first type of igniter or the second type of igniter transmits a response to the controller after receiving an activation signal from the controller.

Abstract: A water heating apparatus including a tank divided into first and second chambers, wherein water in the first and second chambers has first and second temperatures, respectively, a first outlet for supplying water from the first chamber, a first thermostat to measure the first temperature, a second thermostat to measure the second temperature, means for heating water in the second chamber, a pump having a pump inlet in fluid communication with the second chamber and a pump outlet in fluid communication with the first chamber, and a controller configured to initiate pumping of water from the second chamber to the first chamber when the first temperature is below a predetermined first value. The controller is also configured to initiate heating of water in the second chamber when the second temperature is below a predetermined second value, the second value being greater than the first value.

Abstract: A water heater comprising a tank defining a water chamber, a water inlet and a water outlet communicating with the water chamber, and a combustion tube extending generally vertically through the water chamber and having an upper end. The water heater also comprises a coil surrounding the combustion tube and having inlet and outlet ends, a second tube communicating between the combustion tube and the inlet end of the coil, and an exhaust outlet communicating with the outlet end of the coil. The water heater further comprises a gas burner firing into the upper end of the combustion tube, and at least one expansion volume between the upper end of the combustion tube and the inlet end of the coil for attenuating noise.