Abstract: The disclosed technology includes a water heater system having a blower, an igniter, a burner, a heat exchanger, and a refractory configured to attach to the burner and the heat exchanger. The refractory can include a unitary ceramic housing having a top and a plurality of sidewalls and be configured to retain heat from combustion gases. The top can have a burner aperture configured to receive at least a portion of the burner and the plurality of sidewalls can form a cavity configured to receive at least a portion of the heat exchanger. One or more of the sidewalls can additionally have a protrusion extending laterally along an inside surface of the sidewall that is configured to contact the heat exchanger to form a seal between the heat exchanger and the refractory. A sealing material can substantially create a seal between the refractory and the heat exchanger.

Abstract: Disclosed herein are heat exchanger devices comprising an outer shell defining an interior chamber that is configured to pass a heat transfer fluid therethrough, a tube at least partially disposed within the interior chamber and in thermal communication with the heat transfer fluid, the tube being connected to a pool and configured to flow water from the pool therethrough such that the water flowing through the tube exchanges heat with the heat transfer fluid, and a coating disposed on an interior surface of the tube contacting the water from the pool, the coating comprising Nickel. The coating can comprise an additive, such as an electroless Nickel coating. The coating can also be selected from the group consisting of polytetrafluoroethylene (PTFE), Boron Nitride (BN), Silicon Carbide (SiC), aluminum oxide (Al2O3), carbon (C), and carbon allotropes.

Abstract: A combination domestic hot water and space heating system is disclosed. The system includes two refrigerant circuits, one dedicated to heating potable water in a water storage tank and one dedicated to heating a condenser used to heat a space within a building. A controller sends output signals to valves to vary refrigerant flow into the first refrigerant circuit and/or the second refrigerant circuit. The variation in refrigerant flow can be provided by a single multi-directional valve, one or more valves placed at a first end of each refrigerant circuit, and/or one or more electronic expansion valves placed at the end of each refrigerant circuit. Portions of the system can be placed into a single housing, thereby reducing installation costs and labor.

Abstract: The disclosed technology includes a water heater system having a blower, an igniter, a burner, a heat exchanger, and a refractory configured to attach to the burner and the heat exchanger. The refractory can include a unitary ceramic housing having a top and a plurality of sidewalls and be configured to retain heat from combustion gases. The top can have a burner aperture configured to receive at least a portion of the burner and the plurality of sidewalls can form a cavity configured to receive at least a portion of the heat exchanger. One or more of the sidewalls can additionally have a protrusion extending laterally along an inside surface of the sidewall that is configured to contact the heat exchanger to form a seal between the heat exchanger and the refractory. A sealing material can substantially create a seal between the refractory and the heat exchanger.

Abstract: A water heater including a water container; a combustion chamber adjacent the water container; a burner associated with the combustion chamber and arranged to combust fuel to heat water in the container, the burner having a combustion surface and adapted to receive fuel; and a pilot burner including an orifice tube, an outer elongated sheath substantially concentrically positioned around at least a portion of the orifice tube and creating a space between the orifice tube and the sheath, and at least one opening sized and shaped to admit combustion air through the sheath and into the space.

Abstract: A water heater including a water container, a combustion chamber adjacent the water heater, a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, a flue having an upper portion and a lower portion operatively connected to the combustion chamber and extending through at least a portion of the water container, and a catalytic converter located in the upper portion of the flue. The water heater may also reduce NOx and CO emissions generated by a water heater having a radiant burner including activating the burner in response to the temperature of water in the water heater as needed, and substantially removing accumulated foreign matter on the burner by periodically activating the burner irrespective of the water temperature for a selected amount of time.

Abstract: A water heater including a water reservoir container having a cold water inlet and a hot water outlet, a combustion chamber adjacent the water container, a burner associated with the container; a temperature probe associated with the container that detects a water temperature in an upper portion of the container, and a controller that activates the burner, the controller establishing an initial water temperature set point, comparing detected water temperature with the set point when the burner is activated, reducing the set point by a first selected amount when the water temperature decreases by less than a selected amount while the burner is activated or increasing the set point by a second selected amount when the water decreases by a selected amount of more while the burner is activated.

Abstract: A low NOx water heater including a water container, a combustion chamber adjacent the water container; and a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, the burner comprising a plenum chamber having a combustion surface and a device to detect the presence of the collection of lint, dirt and/or oil.

Abstract: A low NOx water heater including a water container; a combustion chamber adjacent the water container; and a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, the burner comprising a plenum chamber having a combustion surface and a device to detect the presence of the collection of lint, dirt and/or oil.

Abstract: An air intake filter for a water heater including a frame structure including a screen, a connector and a receiver positioned to removably engage the connector to position the frame structure at or around an exterior circumferential portion of a water heater.