The invention solves the problem of hot water flow in a domestic hot water installation. The subject of the installation according to the invention is that on a third cold water branch (13) that feeds the heating device (1) a control switch (4) is installed, said switch (4) is connected by control system (11) with hot water flow forcing device (3) set on a second hot water circulation branch (2).

A heat source system managing device includes: a predicted heat demand upper limit calculating unit configured to calculate a predicted heat demand upper limit by adding a prediction error to a predicted heat demand value for a heat source system; an operation plan preparing unit configured to prepare an operation plan of the heat source system to supply heat of the predicted heat demand upper limit to a consuming facility; a surplus stored heat quantity calculating unit configured to repeatedly perform a process of calculating a surplus stored heat quantity by subtracting a heat quantity consumed by the consuming facility from the predicted heat demand upper limit; and an operation plan changing unit configured to sequentially change the operation plan by decreasing a future operation rate of a refrigerator to cancel the surplus stored heat quantity.

An environmental control system is provided and includes equipment to generate an environmental control effect, a damper associated with a zone to control a portion of the environmental control effect permitted to affect the zone by assuming one of various damper positions and a capacity controller operably coupled to the equipment and the damper to control operation of the equipment and to adjust the damper to assume the one of the various damper positions based on a demand of the zone and a capacity of the equipment.

A hot water circulation system comprises a water heater having a cold-water inlet and a hot water outlet. A water pump circulates water through the water heater to produce hot water. The hot water is circulated to a thermal bypass valve, which is configured to close when hot water contacts a heat activated seal. A bypass circuit is coupled between the hot water outlet and the cold water inlet of the water heater. The bypass circuit prevents hot water from circulating from the hot water outlet to the cold-water inlet when the thermal bypass valve is open and promotes circulating hot water from the hot water outlet to the cold water inlet when the thermal bypass valve is closed. Upon a temperature sensor sensing hot water entering the cold-water inlet, the water heater turns of the water pump.

A modularized combined intelligent heat collector system, comprising a PTCR-xthm electric heating chip heat source main engine, a data control template, a constant-temperature and constant-pressure device and a variable-frequency pump; the variable-frequency pump and the PTCR-xthm electric heating chip heat source main engine are connected to the data control template; the outlet end of the PTCR-xthm electric heating chip heat source main engine is connected to the constant-temperature and constant-pressure device; the outlet end of the constant-temperature and constant-pressure device is connected to the PTCR-xthm electric heating chip heat source main engine through the variable-frequency pump; the PTCR-xthm electric heating chip heat source main engine directly leads out a user heating pipeline; and/or the PTCR-xthm electric heating chip heat source main engine leads out the user heating pipeline through the constant-temperature and constant-pressure device, and is connected to a heat exchanger of a user water heater.

Remote control of energy consumption is realized using a readily installable, flexible approach. According to an example embodiment of the present invention, a remote source communicates with a wireless controller for executing energy usage control. The remote source sends signals to the wireless controller via a gateway located near or, in one implementation, forming part of the wireless controller. In response to the signals, the wireless controller sets control settings for operating one or more of a variety of equipment types, such as a furnace, air conditioner, water heater or heat pump. With this approach, wired connections from the gateway to energy-consuming equipment do not necessarily need to be made in order to affect remote energy-consumption control. For instance, when used in connection with a controller wired to the energy-consuming equipment, the gateway need only communicate wirelessly with the controller and does not necessarily need to be coupled to the energy-consuming equipment. In addition, access to the energy-consuming equipment for establishing remote energy control is not necessary; rather, the remote energy control can be effected by accessing user-friendly locations, such as those where thermostats and other controllers are typically located.

An air conditioning system, a set temperature determining device determines a target temperature of water to be supplied to an indoor heat exchanger, based on [“target outflow temperature”=“current outflow temperature”+((“inlet and outlet temperature difference”/“indoor and outdoor temperature difference”)דset temperature difference”)]. The indoor and outdoor temperature difference is a difference between an indoor temperature and an outdoor temperature, the inlet and outlet temperature difference is a difference between temperatures of water at the inlet side and the outlet side of an intermediate heat exchanger, and the set temperature difference is a difference between an indoor temperature and a set temperature. A control device controls an outdoor unit in response to the target temperature determined by the set temperature determining device.

Systems and methods for preventing freeze damage to heating system pipes are provided. In some embodiments, systems for preventing freeze damage to heating system pipes that carry a liquid used to heat a heated space and that are exposed to freezing temperatures outside of the heated space are provided, the systems comprising: a hardware controller that causes the liquid to be circulated through the heating system pipes irrespective of the air temperature in the heated space.

A method of operating a water heater is disclosed. The method includes obtaining a first input corresponding to ambient temperature and a second input corresponding to evaporator temperature. The method includes determining the ambient temperature from the first input and the evaporator temperature from the second input, followed by determining whether the ambient temperature is less than a first threshold temperature. The method includes determining whether the evaporator temperature is less than a second threshold temperature when the ambient temperature is less than the first threshold temperature, where the second threshold temperature is less than the first threshold temperature. The method also includes actuating a heating element coupled to one or more tubes of the evaporator to heat refrigerant present in the one or more tubes, when the evaporator temperature is less than the second threshold temperature.

A heat pump system adjusts a degree of subcooling of an indoor-side heat exchanger in a heating priority mode, and adjusts any one of a degree of subcooling of a hot-water supply-side heat exchanger (water-side heat exchanger) and a discharge temperature of a compressor in a hot-water supply priority mode.