Abstract: Mixing devices for mixing fuel and air for a premix burner or furnace and furnaces (e.g., premix) with mixing devices. Furnaces may be for heating an occupied space, and may produce lower NOx emissions. A mixing device may be located within an inlet tube, may have a surface that is perpendicular to the direction of fuel flow or that forms a circle, or may have two surfaces held at substantially opposite angles to induce swirl. A portion of the mixing device may extend over an orifice of the fuel injector. A mixing device may be attached to the fuel injector, may be made from a piece of sheet metal, and may have a hole for attachment to the fuel injector. Mixing devices may have a center, two arms, and two ends, which may be separated by bends. A burner plate may be sandwiched between surfaces to allow for expansion.

Abstract: Premix furnace for heating an occupied space while producing lower NOx emissions and methods of mixing air and fuel delivered to a premix burner and of improving combustion stability. A mixing device may be located within an inlet tube, may have a flat surface that is perpendicular to the direction of fuel flow, or may have two surfaces held at substantially opposite angles to induce swirl. A mixing device may be attached to the fuel injector, may be made from a piece of sheet metal, and may have bends and a hole for attachment to the fuel injector. A fluidic diode in the inlet tube may improve combustion stability and may include a hollow frustum or a frustoconical portion, a cylinder concentric with the inlet tube, or a combination thereof. Some embodiments include refractory insulation lining the combustion chamber or may adjust for elevation or fuel characteristics.

Abstract: Premix furnace for heating an occupied space while producing lower NOx emissions and methods of mixing air and fuel delivered to a premix burner and of improving combustion stability. A mixing device may be located within an inlet tube, may have a flat surface that is perpendicular to the direction of fuel flow, or may have two surfaces held at substantially opposite angles to induce swirl. A mixing device may be attached to the fuel injector, may be made from a piece of sheet metal, and may have bends and a hole for attachment to the fuel injector. A fluidic diode in the inlet tube may improve combustion stability and may include a hollow frustum or a frustoconical portion, a cylinder concentric with the inlet tube, or a combination thereof. Some embodiments include refractory insulation lining the combustion chamber or may adjust for elevation or fuel characteristics.

Abstract: An improved high-efficiency furnace for use with manufactured housing has a modular heat exchanger assembly having a drum and a plurality of serpentine shaped tubes. A burner extends at least partially into the drum portion of the heat exchanger which acts as a combustion chamber. Hot combustion gases flow upwardly within the drum and enter the tubes heating the drum and tubes. Room air is drawn into the furnace by a circulating blower and blown against the plurality of tubes. The room air is then directed to flow around the drum portion of the heat exchanger where it is further heated before being discharged into the space being heated. The burner includes an inwardly tilted target plate having a plurality of fingers for facilitating the formation of a stable ball of flame within the drum.

Abstract: Required blower power in an induced draft combustion system is reduced by recovering pressure from dynamic energy of flow of combustion products. To this end, the outlet duct is diverged gradually, such as an included angle of less than fifteen degrees, and preferably at an angle of substantially seven degrees. Divergence of the outlet duct may be expressed in polar coordinates having a polar axis, overlapping radius vectors and a variable polar angle of such overlapping radius vectors relative to the polar axis. A difference between such overlapping radius vectors is increased in a direction of flow of the combustion products and the outlet duct is structured with cross-sections increasing incrementally in terms of the increasing difference between the overlapping radius vectors. Condensate may be drained from a combustion product by providing the duct with a lateral offset having a bottom extending at an angle to the earth's field of gravity.

Abstract: Apparatus for providing an admixture of first and second fluids has a first body having opposite ends, a chamber between such opposite ends, an inlet for first fluid into that chamber, and an aperture for the admixture at an end of that chamber. That apparatus also includes a second body having an inlet aperture for second fluid spaced from the first body, an outlet aperture spaced inside the chamber from the aperture for the admixture, and a fluid flow channel decreasing in cross-sectional area from the inlet aperture spaced from the first body to the outlet aperture inside the chamber between opposite ends of the first body. Such first and second bodies jointly comprise a flange structure at the first body and between the inlet and outlet apertures of the second body. An admixture flow channel increases in cross-sectional area away from the aperture at the end of the chamber.

Abstract: Heat is transferred from a first fluid to a cooler second fluid with a heat exchanger having heat exchanger tubes in which the cooler second fluid flows, preferably in a counterflow to the first fluid. The heat exchanger tubes are arranged in more than three rows of heat exchanger tubes. The first fluid proceeds successively downstream through such rows in heat-transfer relationship with the heat exchanger tubes. Each downstream row of heat exchanger tubes has less throughput area for the first fluid than an adjacent upstream row of heat exchanger tubes as among at least the first three rows of heat exchanger tubes in the direction of flow of the first fluid. Each downstream row of heat exchanger tubes may have less heat exchanger tubes than an adjacent upstream row of heat exchanger tubes as among at least the first three of the rows of heat exchanger tubes in the direction of flow of the first fluid.

Abstract: The disclosed methods and apparatus for mixing a secondary fluid with a primary fluid have utility in venturi and other fluid mixing systems in agriculture, fluid, fuel combustion and other fields where liquid or gaseous chemicals, liquid or gaseous fuels or other fluids are entrained in a stream of water, air or other gaseous or liquid primary fluid. One of these methods provides for the primary fluid (21) a first flow channel (65) deceasing in a direction of flow of primary fluid, utilizes dynamic energy of that primary fluid to induce secondary fluid (35) into that primary fluid, and provides for the primary fluid with induced secondary fluid a second flow channel (66) increasing in a direction of flow of that primary fluid with induced secondary fluid, while arranging corresponding sides 67 and 68 of these first and second flow channels along a plane common to said first and second channels.

Abstract: A hinge for a cabinet having a box and a door in an opening of that box, includes a hinge rod having a first offset end portion and a corresponding second offset end portion opposite that first offset end portion and an intermediate rod portion between these first and second offset end portions. A first mounting clip for the first offset end portion is connected either to the box or to the door near the cabinet opening. A second mounting clip for the second offst end portion is connected either to the box or to the door near the cabinet opening. At least one hinge rod mounting bracket for the intermediate rod portion is connected either to the door or to the box. A first slot for either the first offset end portion or for the intermediate rod portion is either in the first mounting clip or in the hinge rod mounting bracket, and a corresponding second slot for either the second offset end portion or for the intermediate rod portion is either in the second mounting clip or in the hinge rod mounting bracket.

Abstract: Methods and apparatus for controlling equipment for operating a spa, provide electrical controls for controlling such equipment, a manual stationary control for manual user operation of these electrical controls, and a manual remote control including a hand-held wireless remote control unit for manual user operation, at least from inside the spa, of the electrical controls operable by the manual stationary control. The manual stationary control is maintained activated for continued manual user operation of the equipment through the electrical controls manually from a control location while the manual remote control remains activated for manual user operation of the equipment through the electrical controls interchangeably with the manual stationary control from the control location and with the hand-held wireless remote control unit at least from inside the spa.

Abstract: A baffle for a tubular structure of at least two pairs of spaced tubes comprises a first baffle sheet having two portions curved in accommodation of spaced tubes in one of the pairs, and a second baffle sheet having another two portions curved in accommodation of spaced tubes in the other of the pairs when said baffle is inserted in between these two pairs of spaced tubes. These first and second baffle sheets are structurally interconnected and biased away from each other for self-clamping retention between the two pairs of spaced tubes. The first and second baffle sheets preferably are spaced from each other for their clearing corresponding spaced tubes when they are moved toward each other against the above menbtioned bias for an insertion in between the pairs of spaced tubes.

Abstract: Water heating methods and apparatus feed a combustible mixture of gas and air to an axial inlet of a cylindrical radiant surface burner and conduct water to be heated through a heat exchanger encompassing that cylindrical radiant surface burner as a cylindrical structure having first passages for combustion gases therethrough substantially radially of the cylindrical radiant surface burner and the heat exchanger.

Abstract: A tub is supplied with hot water through a water circulation system including a pump, a water filter and an electric flow-through heater energized through an electric contactor upon closure thereof. A user of the tub is urged to service the water circulation system upon clogging thereof. For this purpose, water flow fluctuations occurring in the circulation system upon restriction of the water circulation system are sensed and closure of the contactor is precluded for a time interval of predetermined duration in response to a sensing of water flow fluctuations.

Abstract: A control system for a low mass hydronic boiler is disclosed which includes a sensor for measuring the temperature of the fluid exiting the boiler. The level of fuel flow provided to the boiler is reduced when the water temperature exceeds a predetermined high temperature limit. The level of fuel flow provided to the boiler is increased only after the water temperature has decreased below a predetermined reset temperature limit and a predetermined interval of time has elapsed.

Abstract: An electronic temperature control circuit is disclosed for use with swimming pool and spa heaters. The circuit employs a thermistor for sensing water temperature, and provides temperature control with a narrow differential. Safety circuits are also employed to prevent injury to the user or to the heater in the event of a component failure. The temperature control circuit is provided with means for presetting two desired temperature settings and for selecting one of the preset temperature settings for control. Remote control circuits are also disclosed for use with the temperature control circuit which permit temperature selection, temperature setting and a visual indication of heater status from a location remote from the heater.

Abstract: An electronic temperature control circuit is disclosed for use with swimming pool and spa heaters. The circuit employs a thermistor for sensing water temperature, and provides temperature control with a narrow differential. Safety circuits are also employed to prevent injury to the user or to the heater in the event of a component failure. The temperature control circuit is provided with means for presetting two desired temperature settings and for selecting one of the preset temperature settings for control. Remote control circuits are also disclosed for use with the temperature control circuit which permit temperature selection, temperature setting and a visual indication of heater status from a location remote from the heater.