A method for determining whether hot water is used during heating of an air handler system which uses a water heater as a heat source and supplies hot air through a duct for heating is disclosed. The method includes: (a) detecting a flow rate change of tap water supplied to the water heater; (b) detecting a temperature change of the tap water supplied to the water heater; and (c) determining that hot water is used during heating when the flow rate change of the tap water in step (a) and the temperature change of the tap water in step (b) are detected at the same time.

A fluid-based system for use in heating and/or cooling. In particular, the system may have a fluid heating device, which may be a solar fluid heating device, configured to heat a fluid. Heat from the heated fluid may be transferred to one or more cooling subsystems or heating subsystems. A cooling subsystem may be an absorption cooling subsystem, for example, wherein heat may cause phase change of a refrigerant. A heating subsystem may include a storage tank through which heated fluid may be circulated to heat the storage tank. A system of the present disclosure may include multiple cooling and/or heating subsystems for cooling and or heating a variety of different environments, objects, or materials.

A system and method for providing domestic hot water and/or space heating within a building. The system comprises at least one storage vessel comprising a removable cover, wherein an internal volume of the storage vessel is fluidly connected to a source of sewage and/or wastewater from one or more buildings, a water-source heat pump, at least one solar thermal collector, at least one heat transfer circuit. The at least one heat transfer circuit includes at least one fluid line containing a heat transfer fluid, and a controller for controlling an operation of the system. The system has an operation mode in which the controller of the system is configured to connect the at least one solar thermal collector to the at least one storage vessel via the at least one fluid line. The system stores a heat output from the at least one solar thermal collector in sewage and/or wastewater.

A pump (2) system includes a pump, a sensor (22; 28) arranged in or at a flow path (14), and a concentration measurement device measuring a concentration in liquid inside the flow path (14). The concentration measurement device includes the sensor (22; 28), as a concentration sensor, connected to an evaluation device (26) for evaluating readings of the sensor (22; 28). The evaluation device (26) is connected to a further signal source (20; 24), providing at least one further parameter, and is configured to carry out an evaluation of the reading of the sensor (22; 28), taking into account the further parameter provided by the further signal source (20, 24) to output the concentration in the liquid. A solar heating system includes the pump system.

A fluid-based system for use in heating and/or cooling. In particular, the system may have a fluid heating device, which may be a solar fluid heating device, configured to heat a fluid. Heat from the heated fluid may be transferred to one or more cooling subsystems or heating subsystems. A cooling subsystem may be an absorption cooling subsystem, for example, wherein heat may cause phase change of a refrigerant. A heating subsystem may include a storage tank through which heated fluid may be circulated to heat the storage tank. A system of the present disclosure may include multiple cooling and/or heating subsystems for cooling and or heating a variety of different environments, objects, or materials.

A water heater is provided having an insulated tank having a water inlet and a water outlet, and further defining an interior volume to contain a quantity of water. A primary heating arrangement applies heat energy to the water so as to heat the water. In addition, the primary heating arrangement is configured to maintain the water during standby periods between upper and lower set point temperatures. A supplemental heating arrangement is operative to supply additional heat energy to the water in order to lessen energy usage by the primary heating arrangement during the standby periods. In accordance with a preferred embodiment, the supplemental heating arrangement includes at least one photovoltaic panel and a supplemental heating element. Control electronics are operatively interposed between the at least one photovoltaic panel and the supplemental heating element.

Disclosed herein is a solar thermal collector system that is particularly configured for dual use as a radiant cooling system. In accordance with aspects of a particular embodiment of the invention, the solar thermal collector system includes a solar thermal module having a glazing sheet at a top, exterior surface, and an absorber sheet within the module positioned below and spaced apart from the glazing sheet. The absorber sheet and the glazing sheet are fluidly connected to a fluid handling system, and are configured to carry a working fluid that may be heated in the absorber sheet by the sun to transfer such heat to equipment within the facility in which the system is installed, and to carry the working fluid through the glazing sheet to transfer heat collected from the facility to space. The solar thermal collector module is preferably provided a thermally actuated valve that allows the working fluid to also flow through the glazing sheet, which results in self-regulation of the temperature of the module below a critical design temperature.

A hydronic heating system that may depend on pressure in the system for smooth operation. The pressure may be monitored. Pressure in the system may indicate health of the heating system. Certain pressures or variations of pressures may indicate one or more conditions in the system which may be good or adverse. An example of an adverse condition may be leakage of fluid from the system. Analyses of pressures detected in the heating system may be performed by a computer programmed to indicate conditions of the system that are reflected by the detected pressures.

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.

The systems and methods described herein relate to heating ventilation and air conditioning (HVAC) systems and water heating systems in relation to a building and residential automation system. Some embodiments of the systems and methods described herein relate to HVAC systems and water systems in relation to an integration of building or residential automation systems. Specifically, the disclosure relates to maintaining a desirable water temperature for a desirable time period. By reducing unnecessary heating of water, the systems disclosed herein may result in fewer wasted resources and a lower utility bill. In one embodiment, a method for security and/or automation systems may be disclosed. The method may comprise monitoring a status of a water heater and monitoring an occupancy status of a residence. The status of the water heater may adjust, automatically, based at least in part on the monitoring.