Abstract: A heating system of a managed fluid system can include a heat exchanger and a first temperature sensor device that measures an inlet temperature of a fluid flowing into the heat exchanger. The heating system can also include a second temperature sensor device that measures an outlet temperature of the fluid flowing out of the heat exchanger. The heating system can further include a controller communicably coupled to the first temperature sensor device and the second temperature sensor device. The controller can receive inlet temperature measurements made by the first temperature sensor device and outlet temperature measurements made by the second temperature sensor device. The controller can also evaluate the inlet temperature measurements and the outlet temperature measurements using at least one lookup table and at least one algorithm. The controller can subsequently determine an input rate of fuel used to heat the fluid flowing through the heat exchanger.

Abstract: System and methods for controlling operating state of a heat transfer system are disclosed herein. The heat transfer system can include temperature sensor positioned at the fluid inlet line and the fluid outlet line and a heat exchanger between the fluid inlet line and the fluid outlet line. The heat transfer system can include a processor communicatively coupled to the first temperature sensor and the second temperature sensor. The processor can determine an inlet temperature of water flowing in the fluid inlet line and outlet temperature of water flowing in the fluid outlet line and can determine a delta temperature based on difference between the inlet temperature and the outlet temperature. Based on the inlet temperature and the delta temperature, the processor can determine an operating state of the heat transfer system.

Abstract: A water heater can include a heat source and a heat exchanger that transfers heat to the water. A header attached to the heat exchanger provides an inlet and an outlet for water to flow into and out of the heat exchanger. The header can also include an anode assembly that releasably attaches to the header. The anode assembly can be located at a bottom of the header so that an anode in the anode assembly remains in contact with the water when water is flowing through the heat exchanger.

Abstract: Embodiments include various water heaters. In one example, a water heater includes a burner, an exhaust vent, a corrugated baffle having a first slit having a first length and a second slit having a second length that is less than the first length, and a heat exchanger. The heat exchanger includes a first set of heat exchanger tubes arranged in a first row, and a second set of heat exchanger tubes arranged in a second row, the second set of heat exchanger tubes having a third tube having a first angled surface and a second angled surface, where the first angled surface and the second angled surface together form a fin. The third tube can be arranged such that the fin is disposed at least partially between the first curved outer surface and the second curved outer surface.

Abstract: The disclosed technology can include a bypass valve assembly having a partition that can fluidly separate an inlet and an outlet of a fluid heating system. A first bypass valve and a second bypass valve can be mounted to the partition and configured to permit a fluid to flow between the inlet and the outlet. The first bypass valve and the second bypass valve can be configured to transition between a closed state and an open state. The first bypass valve and the second bypass valves can each have a spring configured to transition the respective first and second bypass valve from the closed state in response to experiencing a pressure that is greater than or equal to a respective first or second predetermined pressure. The second predetermined pressure can be greater than the first predetermined pressure.

Abstract: A water heater can include a heat source and a heat exchanger that transfers heat to the water. A header attached to the heat exchanger provides an inlet and an outlet for water to flow into and out of the heat exchanger. The header can also include an anode assembly that releasably attaches to the header. The anode assembly can be located at a bottom of the header so that an anode in the anode assembly remains in contact with the water when water is flowing through the heat exchanger.

Abstract: A water heater can include a baffle and a slab heat exchanger with at least two rows of heat exchanger tubes, each row comprising a plurality of heat exchanger tubes. At least one of the heat exchanger tubes comprises a tube and a plurality of fins on the exterior of the tube circumscribing the tube, wherein the outer edge of each fin of the plurality of fins is bent at least at the same three areas of each fin such that the bends form at least three flat or concave areas running along the length of the heat exchanger tube.

Abstract: A managed water system can include a first body of water contained in a vessel. The managed water system can also include at least one sensor device that measures at least one parameter associated with the first body of water. The managed water system can further include a circulation system that circulates the body of water relative to the vessel. The managed water system can also include a controller communicably coupled to the at least one sensor device and the circulation system. The controller can control the circulation system, and receive measurements of the at least one parameter made by the at least one sensor device. The controller can also evaluate the measurements using multiple algorithms, and communicate a result of evaluating the measurements.

Abstract: System and methods for controlling operating state of a heat transfer system are disclosed herein. The heat transfer system can include temperature sensor positioned at the fluid inlet line and the fluid outlet line and a heat exchanger between the fluid inlet line and the fluid outlet line. The heat transfer system can include a processor communicatively coupled to the first temperature sensor and the second temperature sensor. The processor can determine an inlet temperature of water flowing in the fluid inlet line and outlet temperature of water flowing in the fluid outlet line and can determine a delta temperature based on difference between the inlet temperature and the outlet temperature. Based on the inlet temperature and the delta temperature, the processor can determine an operating state of the heat transfer system.

Abstract: A managed water system can include a first body of water contained in a vessel. The managed water system can also include at least one sensor device that measures at least one parameter associated with the first body of water. The managed water system can further include a circulation system that circulates the body of water relative to the vessel. The managed water system can also include a controller communicably coupled to the at least one sensor device and the circulation system. The controller can control the circulation system, and receive measurements of the at least one parameter made by the at least one sensor device. The controller can also evaluate the measurements using multiple algorithms, and communicate a result of evaluating the measurements.

Abstract: A heating system of a managed fluid system can include a heat exchanger and a first temperature sensor device that measures an inlet temperature of a fluid flowing into the heat exchanger. The heating system can also include a second temperature sensor device that measures an outlet temperature of the fluid flowing out of the heat exchanger. The heating system can further include a controller communicably coupled to the first temperature sensor device and the second temperature sensor device. The controller can receive inlet temperature measurements made by the first temperature sensor device and outlet temperature measurements made by the second temperature sensor device. The controller can also evaluate the inlet temperature measurements and the outlet temperature measurements using at least one lookup table and at least one algorithm. The controller can subsequently determine an input rate of fuel used to heat the fluid flowing through the heat exchanger.

Abstract: A water heater can include a heat source and a heat exchanger that transfers heat to the water. A header attached to the heat exchanger provides an inlet and an outlet for water to flow into and out of the heat exchanger. The header can also include an anode assembly that releasably attaches to the header. The anode assembly can be located at a bottom of the header so that an anode in the anode assembly remains in contact with the water when water is flowing through the heat exchanger.

Abstract: A water heater can include a baffle and a slab heat exchanger with at least two rows of heat exchanger tubes, each row comprising a plurality of heat exchanger tubes. At least one of the heat exchanger tubes comprises a tube and a plurality of fins on the exterior of the tube circumscribing the tube, wherein the outer edge of each fin of the plurality of fins is bent at least at the same three areas of each fin such that the bends form at least three flat or concave areas running along the length of the heat exchanger tube.

Abstract: A managed water system can include a first body of water contained in a vessel. The managed water system can also include at least one sensor device that measures at least one parameter associated with the first body of water. The managed water system can further include a circulation system that circulates the body of water relative to the vessel. The managed water system can also include a controller communicably coupled to the at least one sensor device and the circulation system. The controller can control the circulation system, and receive measurements of the at least one parameter made by the at least one sensor device. The controller can also evaluate the measurements using multiple algorithms, and communicate a result of evaluating the measurements.