A single capacitive sensor that may detect both water leaks and flammable vapors. The sensor may have two electrodes not touching each other but supported with an insulative material between the electrodes that allows fluids to enter between the electrodes. An electronic circuit connected to the capacitive sensor may determine the capacitance of the two electrodes. Fluids may enter between the electrodes and affect their capacitance. Permittivities of the fluids may be calculated from their effects on capacitance. Ranges of the permittivities may indicate the kind of substances and their intensity of presence. Water and flammable vapors are examples of such substances. The electronic circuit may be connected to a control module of a water heater, in that if the intensity or concentration of detected water or flammable vapors reaches a pre-set threshold, then the circuit may trigger an alarm and/or shut down the water heater.

Hot water heating system comprising one or more water heaters with at least one water heating mechanism, and a heating-control storage tank generally configured to store heated water in a temperature stratified manner where hotter water tends to be separated from cold water. The heating-control storage tank can receive thermal energy or hot water from the water heater, send thermal energy or water to the water heater as its makeup water, and provide hot water directly to end users. The water heater may or may not be used to provide hot water to end users. The system is electronically controlled using a processor, various sensors, a recirculation pump, and electronically actuated valves. Depending on hot water needs and energy costs, the system controls water heating schedule and amount of hot water stored in the heating-control storage tank by changing system operation modes to minimize energy costs while providing reliable service.

Techniques for use with vent covers of furnace ductworks are described herein. A vent cover may include a fan to actively pull air from the ductwork and into a room at least in part in response to a number of open or closed vents in ductwork to which the vent cover is connected. Active air movement through the vent cover may lower air pressure and/or temperature within the ductwork and increase airflow through heat exchangers of the furnace, thereby compensating for zones created by closed vent covers. A system may monitor factors consistent with a furnace over-temperature event, such as furnace operation, closed vent covers, high air pressure or temperature in ductwork, etc. A fan of a vent cover may be turned on to actively draw air through a vent covered by the vent cover. The fan may turn off after conclusion of at least one of the monitored factors.

The present disclosure relate to a controller system and method for use in storage-style water heating systems that offers significant opportunities for energy saving. The controller system can adjust the water heating system in response to energy demand patterns of user fixtures. The controller system can detect quantity of heated water usage and produce a heated water usage profile. The controller system can determine the quantity or volume of the used heated water without a mechanical flow meter. The controller system can include a cost-effective, accurate, and easy-to-install water temperature sensors that provide measurements of the differentials between water temperatures without direct contact with the water. The water temperature sensors can be cost-effective and easy-to-install sensors that are attached to the water pipes through a strap or other attachment methods.

A water heating system can include 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 a plurality of algorithms and measurements made by the first and second temperature sensors. The plurality of algorithms solves for at least one calculated temperature for at least one point between a first location of the first temperature sensor and a second location of the second temperature sensor, where the at least one calculated temperature is used to determine the amount of heated water in the tank.

A water heating system can include 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 a plurality of algorithms and measurements made by the first and second temperature sensors. The plurality of algorithms solves for at least one calculated temperature for at least one point between a first location of the first temperature sensor and a second location of the second temperature sensor, where the at least one calculated temperature is used to determine the amount of heated water in the tank.

A building management system (BMS) gateway comprises a BMS router and a water heater hub configured to be communicatively coupled to a plurality of water heaters. The BMS router facilitates communication of status and control data between a BMS and the water heaters connected to the water heater hub. Connecting multiple water heaters to a single BMS gateway provides simplified installation and networking requirements. For installations with more water heaters than are able to be coupled to the water heater hub, additional BMS gateways may be installed. Local controls for water heaters managed by the BMS are typically disabled or overwritten by the BMS to prevent changes to settings. A local BMS user interface (UI) is configured to connect with the BMS gateway(s) and facilitate secure access, display, and/or adjustment of water heater status and control data for the plurality of water heaters connected to the BMS gateway(s).

A building management system (BMS) gateway comprises a BMS router and a water heater hub configured to be communicatively coupled to a plurality of water heaters. The BMS router facilitates communication of status and control data between a BMS and the water heaters connected to the water heater hub. Connecting multiple water heaters to a single BMS gateway provides simplified installation and networking requirements. For installations with more water heaters than are able to be coupled to the water heater hub, additional BMS gateways may be installed. Local controls for water heaters managed by the BMS are typically disabled or overwritten by the BMS to prevent changes to settings. A local BMS user interface (UI) is configured to connect with the BMS gateway(s) and facilitate secure access, display, and/or adjustment of water heater status and control data for the plurality of water heaters connected to the BMS gateway(s).

An aspect of some embodiments of the current invention relates to an integrated system for heat distribution among a plurality of users. In some embodiments, the system includes a separate automatic control of heat distribution to each user and/or separate billing to each user. For example, a system may supply hot fluid to a plurality of apartments in a building and/or in multiple buildings. Optionally, each apartment has separate remote controlled valves controlling flow of heated fluid to the apartment and/or a sensor sensing how much heat enters and leaves the apartment in the hot fluid. In some embodiments, a processor controls the valve and/or receives data from sensors. The processor optionally controls devices that generate and/or store and/or dissipate heat. Optionally the processor predicts energy availability, costs and needs controls valves and/or devices to provide for predicted and/or unexpected needs while reduce cost of the energy.

A liquid heating system includes an instantaneous heater (18) having an inlet (20) connected to a reservoir (62). The outlet (22) of the heater is connected to fixtures (72) which use the heated liquid, and is also connected through a return connection (30) to the reservoir. In an idle mode, a pump 40 draws liquid from the reservoir (62), so that the liquid circulates through the heater and back to the reservoir. A controller (52) actuates the heater to heat the liquid to a first setpoint temperature, so that the liquid in the reservoir stabilizes at the first setpoint temperature. In a supply mode, some or all of the heated liquid flows from the outlet to the fixtures (72). Cold liquid is admitted from a supply (60) to the reservoir, and cold liquid desirably also is supplied to the heater inlet along with liquid from the reservoir, so that the heater inlet receives a combination of these. The controller controls the proportion of cold liquid to liquid from the reservoir in the combination, so as to maintain the heater at a setpoint heating rate while also maintaining the temperature of liquid discharged from the heater outlet at or near a setpoint temperature.