Disclosed herein are connectors for a tankless water heater. The connectors can comprise a flange, an aperture extending through the flange having a first diameter, one or more slots extending through the flange, a connector portion substantially surrounding the aperture and extending outward from the flange away from the tankless water heater. The aperture can correspond to an air inlet extending into the tankless water heater, and the air inlet can have a second diameter that is larger than the aperture. To keep the flange in place, the one or more slots can correspond to one or more fastening holes in the tankless water heater. The one or more slots can be substantially parallel and on opposite sides of the aperture. The connector can be in a secured state when the one or more slots are fastened to the one or more fastening holes.

A vent apparatus is used to install a tankless water heater or similar equipment inside an attic without going onto the roof. The vent apparatus may include a main housing and an umbrella assembly movably disposed therein. The main housing (e.g., PVC pipe) is installed through the roof. The umbrella assembly may have a central rod with a flexible umbrella cover on top and an engagement member on bottom. The umbrella assembly is pushed up through the main housing until the engagement member hits the bottom of the main housing and the umbrella cover exits the top of the main housing to cover it and prevent rain from entering the main housing. The bottom of the main housing is then connected to the tankless water heater. Additional embodiments are disclosed for tankless water heaters with an air intake port and a gas exhaust port.

A water heater includes a first heater, a second heater, and a controller. The controller can enable different operational modes of the water heater, wherein only the first heater operates, only the second heater operates, or both the first and the second heaters operate. The controller can also be configured to enable a hybrid operational mode and a bypass operational mode. Further, in the different operational modes, the controller can direct water flow to at least one of a first conduit coupled to the first heater, a second conduit coupled to the second heater, and a bypass conduit. The controller can be configured to receive input signals relating to environmental conditions around the water heater and/or an aquatic system in which the water heater is installed.

Disclosed herein are connectors for a tankless water heater. The connectors can comprise a flange, an aperture extending through the flange having a first diameter, one or more slots extending through the flange, a connector portion substantially surrounding the aperture and extending outward from the flange away from the tankless water heater. The aperture can correspond to an air inlet extending into the tankless water heater, and the air inlet can have a second diameter that is larger than the aperture. To keep the flange in place, the one or more slots can correspond to one or more fastening holes in the tankless water heater. The one or more slots can be substantially parallel and on opposite sides of the aperture. The connector can be in a secured state when the one or more slots are fastened to the one or more fastening holes.

A fluid heating apparatus according to an embodiment disclosed herein may include a burner, a heat exchanger, a first flow rate sensor that detects a flow rate of a fluid supplied to the heat exchanger, a temperature sensor that detects a temperature of a fluid discharged from the heat exchanger, and a controller that controls a first pump provided in an internal circulation flow path on the basis of the flow rate detected by the first flow rate sensor to manage the flow rate of the fluid supplied to the heat exchanger and controls an operation of the burner on the basis of the temperature detected by the temperature sensor.

The present invention provides a large-scale water heater with a telescoping tower having a tower with a storage area proximal to the bottom of the tower; a portion of the tower that telescopes vertically that is pre-filled with a packing media; a nozzle designed to distribute a fluid that is located above the packing media; a firing chamber with a proximal end in fluid communication with the tower; and a burner in fluid communication with the distal end of the firing chamber for combusting fuels.

To facilitate a wall-mounted installation of multi-unit water heaters in a location with limited clear wall space, spacer brackets may be installed on the wall to extend a mounting surface away from a plane of the wall. A mounting bracket may be attached to the mounting surface of the spacer brackets. To reduce installation time and costs, a plurality of water heaters may be affixed to a frame prior to installation. A hot water, cold water, and fuel supply manifolds may be coupled to each hot water outlet, cold water inlet, and fuel supply inlet, respectively, of the plurality of water heaters. The mounting bracket comprises a mounting shelf configured to receive the frame, thereby securing the multi-unit water heater system to the wall. The multi-unit water heating system, the spacer brackets, and the mounting bracket may be provided as a kit.

A heat exchanger having a first heat exchanger tube and a second heat exchanger tube is disclosed. The first heat exchanger tube can have a first leg, a second leg, and a bend section, and the bend section of the first heat exchanger tube can include three or more bends, each of the three or more bends having a corresponding bend angle that is less than or equal to approximately 90 degrees. The second heat exchanger tube can have a first leg, a second leg, and a bend section, and the bend section of the second heat exchanger tube can include three or more bends, each of the three or more bends having a corresponding bend angle that is less than or equal to approximately 90 degrees.

A heat exchanger includes fins and a plurality of pairs of cut-and-raised parts. Each pair of the cut-and-raised parts are positioned on both left and right sides in a width direction on a downstream side in a heating gas flowing direction around an outer circumference surface of each of upstream pipe body parts and face a downstream part on the outer circumference surface with a first gap therebetween. A width between upstream end parts of each pair of the cut-and-raised parts is larger than an outer diameter of each of the upstream pipe body parts. In addition, each pair of the cut-and-raised parts are inclined such that a width between downstream end parts becomes smaller than the width between the upstream end parts. A heating gas passing part having a width narrower than a dimension therebetween is provided in a region between two adjacent upstream pipe body parts.

Embodiments of the invention provide a pool heater including a housing, a first tankless heater, a second tankless heater, and a controller. The controller is configured to activate only the first tankless heater when a first condition is met, activate only the second tankless heater when a second condition is met, and activate the first and the second tankless heaters simultaneously when a third condition is met.