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.

In an immediate hot water supply operation mode in which a circulation pump is activated while a hot water supply faucet is closed, a water heating apparatus forms an immediate hot water supply circulation path by an inner path including a water entry path, a heat exchanger, and a hot water output path and an outer path bypassing the hot water supply faucet, as being combined. A controller stores as an actual flow rate value for each immediate hot water supply operation mode, a flow rate detection value by a flow rate sensor at predetermined timing, and calculates a flow rate learning value based on a plurality of stored actual flow rate values. When the flow rate detection value becomes larger than a criterion value set in accordance with the flow rate learning value, use of the hot water supply faucet is detected and the circulation pump is deactivated.

A device that includes a pressure sensor that adds dynamic pressure sensing capability to a furnace. In some examples the device may include a relay and other circuitry to replace the single-setpoint pressure switch used to sense the operation of an inducer fan. The pressure sensor may measure the pressure from the inducer fan and send a signal to the other circuitry, such as a microcontroller. The other circuitry may determine when the pressure from the inducer fan reaches a predetermined threshold and allow the main gas valve of the furnace to open. The other circuitry may be configured to set the pressure sensor to a variety of predetermined pressure thresholds, and thereby replace multiple pressure switches. In some examples, the other circuitry may record pressure values received from the pressure sensor over time and provide performance data, as well as other signals or indicators.

A diagnostic method for verifying the proper functioning of flow devices of a fluid system including at least one of at least one fluid heater, a bypass conductor connected in parallel to the at least one fluid heater, a bypass valve configured to control flow through the bypass conductor, at least one flow valve for controlling a fluid flow through the fluid system, at least one pump, at least one pressure sensor for obtaining a pressure of the fluid flow and at least one flow sensor for obtaining a flowrate of the fluid flow. The method includes selectively turning on and off the bypass valve and the at least one pump and obtaining pressure measurements at various times during the execution of the diagnostic method to identify the health of the at least one pressure sensor and the at least one pump.

A diagnostic method for verifying the proper functioning of flow devices of a fluid system including at least one of at least one fluid heater, a bypass conductor connected in parallel to the at least one fluid heater, a bypass valve configured to control flow through the bypass conductor, at least one flow valve for controlling a fluid flow through the fluid system, at least one pump, at least one pressure sensor for obtaining a pressure of the fluid flow and at least one flow sensor for obtaining a flowrate of the fluid flow. The method includes selectively turning on and off the bypass valve and the at least one pump and obtaining pressure measurements at various times during the execution of the diagnostic method to identify the health of the at least one pressure sensor and the at least one pump.

A method of determining calcification of at least a portion of a water heating assembly in a home appliance having a treating chamber. The method includes supplying heated water to the treating chamber via the water heating assembly. The water heating assembly includes a heating element that is selectively energized. A number of thermostat trips are sensed during at least a portion of a cycle of operation. A water temperature value indicative of a water temperature can be sensed. A calcification level of the heating element or the at least a portion of the water heating assembly can be determined based on the number of thermostat trips and the water temperature value.

A method of determining calcification of at least a portion of a water heating assembly in a home appliance having a treating chamber. The method includes supplying heated water to the treating chamber via the water heating assembly. The water heating assembly includes a heating element that is selectively energized. A number of thermostat trips are sensed during at least a portion of a cycle of operation. A water temperature value indicative of a water temperature can be sensed. A calcification level of the heating element or the at least a portion of the water heating assembly can be determined based on the number of thermostat trips and the water temperature value.

The disclosed technology includes a tankless liquid heater system for detecting buildup on a heating element, including: a chamber; at least one heating element to heat liquid in the chamber; at least one sensor to detect data associated with identifying buildup on the at least one heating element; and at least one device to: receive the data detected by the at least one sensor; determine, based on the data, an amount of the buildup on the at least one heating element; and adjust an operation of the at least one heating element based on the amount of the buildup on the at least one heating element.

The disclosed technology includes a tankless liquid heater system for detecting buildup on a heating element, including: a chamber; at least one heating element to heat liquid in the chamber; at least one sensor to detect data associated with identifying buildup on the at least one heating element; and at least one device to: receive the data detected by the at least one sensor; determine, based on the data, an amount of the buildup on the at least one heating element; and adjust an operation of the at least one heating element based on the amount of the buildup on the at least one heating element.

Disclosed herein is a water heating system including a water heater having a tank, and a first temperature sensor disposed toward a top end of the tank to measure a first temperature and a second temperature sensor disposed toward a bottom end of the tank to measure a second temperature. The water heating system can further include a controller communicably coupled to the first temperature sensor and the second temperature sensor, where the controller determines an amount of heated water in the tank based on one or more algorithms and measurements made by the first and second temperature sensors.