Various embodiments include a method of controlling heat exchange via a terminal unit of a terminal-side circuit of a system for HVAC with a source-side circuit coupled to the terminal-side circuit comprising: reading a terminal-side supply temperature signal; producing a supply temperature from the terminal-side supply temperature signal; estimating a percentage demand signal as a function of the supply temperature; estimating an actual demand for power by rescaling a value of maximum available power by the percentage demand signal; comparing the actual demand for power to the value of maximum available power; and if the actual demand for power exceeds the value of maximum available power: producing a first flow control signal based on the value of maximum available power; and controlling a flow of a fluid through the source-side circuit based on the first flow control signal.

A valve having a balancing function for a fluid distribution system. A valve closing member is movable between a closed position and a fully opened position. An actuation device is provided for changing the position of the valve closing member. A control unit is provided and includes an electronic memory adapted to receive and store an opening limitation value, the opening limitation value being representative of a selected intermediate position between the closed position and the fully opened position of the valve closing member, wherein the control unit controls the actuation device to limit the movement of the valve closing member to positions from the closed position to the selected intermediate position. Also, a valve system and to a method of operating a valve.

The present invention proposes a balancing valve, a fluid network with such a balancing valve, and a method of maintaining such a balancing valve. The balancing valve comprises a housing having a main fluid passage extending along a main flow axis, a valve body disposed within the housing in the fluid passage, wherein the valve body has a first through hole forming a first fluid passage with a variable first fluid passage cross section. The valve body has a second through hole distinct from the first through hole and forming a second fluid passage in the valve body. The first fluid passage is a main fluid passage and the second fluid passage is a by-pass passage.

For balancing a hydronic network that comprises a plurality of parallel zones with a regulating valve in each zone, individual flow characteristics are determined (S1) for each of the regulating valves, by recording the total flow of fluid measured at different valve positions of a respective regulating valve, while the remaining other regulating valves are set to a closed valve position. Dependent flow characteristics are determined (S2) by recording the total flow of fluid measured at different valve positions of the respective regulating valve, while the remaining other regulating valves are set to an open valve position. Correction factors are determined (S3) for each of the regulating valves, using the individual flow characteristics and the dependent flow characteristics. The hydronic network is balanced (S4) by setting the valve positions of the regulating valves using target flows and the correction factors.

The present invention is a fluid distribution system comprising connected conduits (e.g., lines) wherein fluid flows, such as pipes within a building. The lines may be configured to: (i) include multiple lines that connect at intersections (some of the intersections will be identified as nodes); and (ii) incorporate node units associated with line pressure loss simulation assemblies (“LLSAs”). Activities of a node unit incorporating a LLSA can result in alterations in fluid pressure, such as by a loop control process to reposition balancing valves or other valves of one or more LLSAs, and/or by alteration of the speed of the system pump. These activities adjust fluid pressure to cause the system to produce a balanced and high efficiency energy transfer (e.g., heating or cooling), and do not involve or require any identification or use of any specific, fixed or absolute pressure value. They function based on an operation locus (for a node unit) and/or an operation locus range (for node unit groupings) to adjust the fluid pressure.

The present invention proposes a balancing valve, a fluid network with such a balancing valve, and a method of maintaining such a balancing valve. The balancing valve comprises a housing having a main fluid passage extending along a main flow axis, a valve body disposed within the housing in the fluid passage, wherein the valve body has a first through hole forming a first fluid passage with a variable first fluid passage cross section. The valve body has a second through hole distinct from the first through hole and forming a second fluid passage in the valve body. The first fluid passage is a main fluid passage and the second fluid passage is a by-pass passage.

Various embodiments include a method of controlling heat exchange via a terminal unit of a terminal-side circuit of a system for HVAC with a source-side circuit coupled to the terminal-side circuit comprising: reading a terminal-side supply temperature signal; producing a supply temperature from the terminal-side supply temperature signal; estimating a percentage demand signal as a function of the supply temperature; estimating an actual demand for power by rescaling a value of maximum available power by the percentage demand signal; comparing the actual demand for power to the value of maximum available power; and if the actual demand for power exceeds the value of maximum available power: producing a first flow control signal based on the value of maximum available power; and controlling a flow of a fluid through the source-side circuit based on the first flow control signal.

A flow control valve comprises three orifices. Each of the three orifices is connectable to a fluid conduit, respectively. Each of two orifices of the three orifices is modulatable between a closed mode in which that orifice is substantially closed, and an open mode in which that orifice is open. Each of the two orifices is also modulatable between the closed mode and the open mode while the other one of the two orifices is in the closed mode. Depending on the application, the orifices may be used as inlets or outlets and in different combinations of inlets and outlets. A hydronic system that includes the flow control valve is also described.

A circulating hot water system has a hot water flow circuit defined by pipework leading out from and back to an in-line heater, and including a pump to drive circulation of the hot water. Each of multiple user points has an outflow branch conduit and a return flow branch conduit with a common wall for heat exchange, as does the main flow circuit: the outflow conduit surrounds the return conduit. Water is fed into the system from a pressurized cold water supply main through a check valve. Sensors are used to monitor water temperatures and flow conditions around the system. A programmed control processor can control heating and pumping rates in various regimes, e.g. to maintain system temperature above a predetermined threshold. An isolation valve adapted for concentric double pipes is also described.

A self-adjusting balance valve controller controls water flow through a hydronic emitter in a heating and/or cooling temperature control system. The valve controller obtains a measured temperature differential between an inlet and an outlet of the hydronic emitter and determines a displacement of a coupling pin from the measured temperature differential. The valve controller then instructs a driving mechanism to move, through a coupling mechanism, the coupling pin to adjust a valve that results in a desired water flow through the hydronic emitter. The valve controller may maintain a stable temperature differential at a desired differential value, which may be obtained through a user interface or from a memory device. Moreover, the desired differential value may vary with different times of operation or temperature control situations.