A system comprising a main circuit for routing a flow of heat transfer liquid out of a thermal storage to at least one outer heat exchanger and back to the thermal storage again, a main circulation pump configured to force the heat transfer liquid through the main circuit, a temperature sensor configured to measure the temperature of the heat transfer liquid, and a controller configured to control the main circulation pump based on temperature readings of the temperature sensor such that a calculated Reynolds number for the flow of heat transfer liquid is constant at a predetermined target Reynolds number over at least a primary temperature range.

The invention is an apparatus for heating or cooling a room of a building. The apparatus includes a radiant panel supported on a wall, which radiates energy to or from a room. The radiant panel has a conduit for passage of a fluid. The invention also includes a heat exchange device which heats or cools the fluid, which is installed inside the wall between two studs. A first line and second line connect the inlet and outlet to the heat exchange device. A pump that pumps the fluid that is heated or cooled by the heat exchange, whereby the room is heated or cooled depending on whether the fluid is heated or cooled by the heat exchange device.

A system for heating a first fluid flow from a first temperature to a second temperature, the system including a hot water supply line for receiving the first fluid flow at a first end and exhausting the first fluid flow at a second end; and a heating system including a heat engine, a thermal battery and a heat exchanger, wherein the thermal battery is configured to be replenished at a point of heat transfer by the heat engine and the hot water supply line is configured to receive heat from the thermal battery via the heat exchanger to elevate the temperature of the first fluid flow from the first temperature to the second temperature.

A district energy distributing system is disclosed. The system comprises a geothermal heat source system comprising a geothermal heat source and a feed conduit for a flow of geothermally heated water from the geothermal heat source. The system further comprises a district feed conduit, a district return conduit and a plurality of local heating systems, each having an inlet connected to the district feed conduit and an outlet connected to the district return conduit, wherein each local heating system is configured to provide hot water and/or comfort heating to a building, A central heat exchanger is connected to the feed conduit of the geothermal heat source system such that an incoming flow of geothermally heated water is provided to the central heat exchanger.

A system for producing a cooled liquid and a heated liquid. Such a system may be embodied in the form of a unitary apparatus configured to dispense chilled water and near boiling water for human consumption. In one form, there is provided a system for heating and cooling a liquid, the system including: a liquid cooling unit having a heat output component, and a first liquid heater configured to hold and heat a liquid. The first liquid heater is configured to retain a first body of the liquid about the heat output component such that the liquid is heated, and furthermore that a temperature gradient is formed and maintained within the first body of the liquid.

A method of protecting a single-stage furnace in a multi-zone system includes monitoring a temperature of each zone of a plurality of zones, determining if the temperature of at least one zone of the plurality of zones is less than a threshold temperature, powering on the HVAC system to satisfy a heating demand of the zone having a temperature less than the threshold temperature, monitoring an outlet temperature of the single-stage furnace, determining if the outlet temperature is greater than an outlet temperature threshold, and responsive to a determination that the outlet temperature is greater than the outlet temperature threshold, modulating a gas valve to reduce a flow of gas to the single-stage furnace.

The present invention provides a cold-storage instantaneous heat pump water heater (HPWH). The HPWH includes a cold-water tank, a main evaporator, a compressor, and a hot water heat exchanger. In the present invention, heat of a working medium in the cold-water tank is absorbed by the main evaporator, and bathing water is rapidly heated by the hot water heat exchanger (condenser of the heat pump), thereby realizing instant heating with small input electrical power. Cold-water tank replaces the hot water tank of conventional HPWH avoiding energy loss during hot water storage. The working medium in the cold-water tank absorbs heat from the environment, to further improve energy utilization. In addition, there are three energy recovery evaporators to recover the waste heat of bathing.

A heat pump water heater has a tank, a heat source, and a heat pump system. The heat pump system has a refrigerant path, at least a portion of which is in thermal communication with the water tank volume so that heat transfers from refrigerant to the water tank volume. A fan causes air to flow through a housing, and another portion of the refrigerant path includes an evaporator in the housing. The fan is within the housing and may further be within a second housing. The first housing may comprise a baffle to direct air flow. The fan may be a variable speed fan in communication with a controller, so that the controller controls the fan speed depending on a temperature of the refrigerant.

A settings data storage stores unique serial numbers and information regarding a plurality of patterns for alternately switching between normal operation for operating at high capacity and suppressed operation for operating at low capacity each unit time. A pattern specifier determines information for a pattern set in accordance with even and odd serial numbers. A water-heating heat amount determiner determines a heat amount necessary for water heating. A water heating scheduler establishes a water heating plan based on information regarding the pattern determined by the pattern determiner and the water-heating heat amount as determined by the water-heating heat amount determiner. A water heating controller alternately switches between normal operating and suppressed operation to heat water in accordance with the water heating plan established by the water heating scheduler.

A hot water supply apparatus includes a heat pump device in which a compressor and a heat exchanger are connected, a heat medium circuit connected to the heat pump device via the heat exchanger, a tank that stores water after the water exchanges heat with a heat medium of the heat medium circuit, two tank-temperature detection units attached at different heights to the tank and each detects a temperature of water in the tank, and a controller that controls, by using a value detected by each of the two tank-temperature detection units, a temperature of water in the tank. The controller sets a target hot water supply temperature based on a stored-hot-water temperature detected by one of the two tank temperature detection units and a within-tank temperature difference that is a difference between temperatures within the tank detected by the two tank-temperature detection units.