A heat pump apparatus includes a use-side heat exchanger that cause heat exchange to be performed between a heat medium flowing from a heat-storage heat exchanger and a heat usage medium, and a flow-passage switching device that switches a flow passage for the heat medium to a first flow passage that circulates through a heat-reception-side heat exchanger and the heat-storage heat exchanger without extends through the use-side heat exchanger or a second flow passage that circulates through the heat-reception-side heat exchanger and the heat-storage heat exchanger via the use-side heat exchanger. Even when the temperature of the heat storage medium rises, heat received from a heat source can be stored in the heat storage medium by a heat pump, while a decrease of the efficiency of the heat pump can be reduced.

A hot water supply system 400 comprises a cold water inlet 402 coupled to a valve 404 which determines the degree of flow in a first path 406 and a second path 408. The first path comprises an Energy Storage Arrangement including a heat exchanger 410 which can heat the water from the inlet. The second path includes an electrical heater 422 which can also heat water from the inlet. The two paths each include a respective flow sensor 416, 428 and the paths re-join before providing an outlet 420 from the supply system via a temperature sensor 418. A controller 430 controls the valve 404 and the electrical heater 422 in response to the sensor signals to provide hot water at a desired temperature using a suitable proportion of stored energy and electrical energy. By charging the Energy Storage Arrangement using a heat pump, an economical and responsive hot water supply system is provided.

A hot water supply system 400 comprises a cold water inlet 402 coupled to a valve 404 which determines the degree of flow in a first path 406 and a second path 408. The first path comprises an Energy Storage Arrangement including a heat exchanger 410 which can heat the water from the inlet. The second path includes an electrical heater 422 which can also heat water from the inlet. The two paths each include a respective flow sensor 416, 428 and the paths re-join before providing an outlet 420 from the supply system via a temperature sensor 418. A controller 430 controls the valve 404 and the electrical heater 422 in response to the sensor signals to provide hot water at a desired temperature using a suitable proportion of stored energy and electrical energy. By charging the Energy Storage Arrangement using a heat pump, an economical and responsive hot water supply system is provided.

Provided is an energy bank including a heat exchanger, the energy bank comprising an enclosure, and within the enclosure: an input-side circuit of the heat exchanger for connection to an energy source; an output-side circuit of the heat exchanger for connection to an energy sink; and a phase-change material for the storage of energy; the energy bank including one or more sensors to provide measurement data indicative of the amount of energy stored as latent heat in the phase change material, the energy bank comprising an optical source to launch light into the phase change material, and the one or more sensors includes an optical sensing arrangement to detect light launched from the optical source after the light has passed through the phase change material, wherein the optical source and the optical sensing arrangement is configured to give a graduated measure of a plurality of different energy storage states from empty to full.

Also provided are: an installation including such an energy bank coupled between a heat pump and the hot water system, a processor being configured to make a determination to trigger the starting of the heat pump based on measurement data from the sensors; and a method of controlling a heat pump in such an installation, the method comprising using measurement data from the one or more sensors to trigger the starting of the heat pump.

Provided is a method of signalling energy usage to a user of a hot water outlet of a hot water supply system, the hot water supply system including: a thermal energy store that is supplied with energy from a source of renewable energy; a renewable energy source; an auxiliary water heater coupled to a networked energy supply; a flow transducer operable, when a water flow passes through the hot water outlet, to provide flow rate data for the water flow; and a processor coupled to the flow transducer; the hot water supply system being operable, under the control of the processor, to heat water that is to be supplied to the hot water outlet to a target system supply temperature using a selection of one or more of the auxiliary water heater, the renewable energy source, and energy from the thermal energy store.

A hydraulic unit is for use in a multi zone heating system. The hydraulic unit comprises a variable output pump; a plurality of independently controllable valves, each valve being associated with one heating zone; and at least one temperature sensor. Each heating zone receives a heated water supply from a common heat source via the pump. The heating system includes a controller comprising a processor which receives signals from the at least one temperature sensor which processes the signals in accordance with control software. Command signals are sent to the pump and the plurality of independently controllable valves, to vary the flow rate of water from the common heat source to each of the heating zones independently one to another. Remote fault diagnosis and control is also provided.

A hydraulic unit is for use in a multi zone heating system. The hydraulic unit comprises a variable output pump; a plurality of independently controllable valves, each valve being associated with one heating zone; and at least one temperature sensor. Each heating zone receives a heated water supply from a common heat source via the pump. The heating system includes a controller comprising a processor which receives signals from the at least one temperature sensor which processes the signals in accordance with control software. Command signals are sent to the pump and the plurality of independently controllable valves, to vary the flow rate of water from the common heat source to each of the heating zones independently one to another. Remote fault diagnosis and control is also provided.

An installation includes an in-building hot water supply system, a hot water heat pump, an energy storage arrangement containing a mass of phase change material and a heat exchanger coupled between the hot water system and the heat pump, and a processor to provide a signal to the heat pump based on the opening of an outlet of the hot water supply system. The mass of phase change material has enough latent heat capacity to heat to a predetermined temperature a predetermined quantity of water in the interval from the opening of an outlet of the hot water supply system until at least the heat pump begins to heat water in the hot water supply system. Also provided is a method of controlling a heat pump in such an installation.

According to an aspect of the present disclosure, there is disclosed a method of determining the use of hot water performed in a system including a water heater and an air handler. The method includes: sensing a temperature of influent flowing into the water heater;

sensing a temperature of effluent flowing out of the air handler; calculating a temperature difference between the temperature of the influent and the temperature of the effluent; and determining whether hot water is used by calculating whether the temperature difference is greater than a predetermined value.

The purpose of the present invention is to provide a control device, a heat source system, a control method, and a control program with which a heat medium at a required temperature can be more effectively sent out. This control device, which is applied to a heat source system 1 comprising a plurality of heat source machines (2a), (2b) connected in series, comprises a setting unit which sets the outlet setting temperatures of cool water in the respective heat source machines (2a), (2b) on the basis of: a measured value of a cool water flow rate, measured values of inlet temperatures of the cool water in the respective heat source machines (2a), (2b); and the required outlet temperature of the cool water in the heat source system (1).