Method for operating and/or monitoring an HVAC system

A method for adaptively operating and/or monitoring a Heating Ventilation Air-conditioning (HVAC) system (10) under control of a controller (21, 22), the method comprising:

• circulating a medium in a primary circuit (26), such that the medium flows through at least one energy consumer (11, 12, 13), the medium entering at a volumetric rate of flow (φ) into an energy consumer (11, 12, 13) through a supply line (14) at a supply temperature (Tv) and leaving the energy consumer (11, 12, 13) at a return temperature (TR) by way of a return line (15) and, in so doing, releases heat energy or cold energy to the energy consumer (11, 12, 13) in a flow of energy (E),
• empirically determining a dependence of a temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) for the respective energy consumer (11, 12, 13),
• adaptively changing operation of the HVAC system (10) in accordance with the determined dependence and/or dependences,
• wherein the dependence of the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) is repeatedly determined empirically at varying time intervals by the controller,
• whereby the volumetric flow rate (φ) and the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) are measured simultaneously at different points in time and, if desired, the associated flow of energy (E) is determined for each of the points in time from associated measurement values and assigned to a respective volumetric rate of flow (φ) in order to determine empirically the dependence of the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ), while the system is running, over a sufficiently long period to time,
• wherein, on the basis of the determined dependence, a lower limit value (ΔTmin) of the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) is established,
• wherein said lower limit value is not undershot while the HVAC system (10) is running,
• wherein a control valve (19) with characteristic curves and being controlled by the controller (21) is used for open and/or closed loop control of the volumetric rate of flow (φ) in the primary circuit (26), and
• wherein a pressure differential (Δp) occurring at the control valve (19) is determined by the controller (21) from the measured volumetric flow rate (φ) in accordance with the characteristic curves of the control valve (19) and the valve position, and, if required, is used for controlling and/or monitoring purposes.

A method for adaptively operating and/or monitoring a Heating Ventilation Air-conditioning (HVAC) system (10) under control of a controller (21, 22), the method comprising:

• circulating a medium in a primary circuit (26), such that the medium flows through at least one energy consumer (11, 12, 13), the medium entering at a volumetric rate of flow (φ) into an energy consumer (11, 12, 13) through a supply line (14) at a supply temperature (Tv) and leaving the energy consumer (11, 12, 13) at a return temperature (TR) by way of a return line (15) and, in so doing, releases heat energy or cold energy to the energy consumer (11, 12, 13) in a flow of energy (E),
• empirically determining a dependence of the flow of energy (E) and/or a temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) for the respective energy consumer (11, 12, 13),
• adaptively changing operation of the HVAC system (10) in accordance with the determined dependence and/or dependences,
• wherein the dependence of the flow of energy (E) and/or the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) is repeatedly determined empirically at varying time intervals by the controller,
• whereby the volumetric flow rate (φ) and the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) are measured simultaneously at different points in time and, if desired, the associated flow of energy (E) is determined for each of these points in time from associated measurement values and assigned to a respective volumetric rate of flow (φ) in order to determine empirically the dependence of the flow of energy (E) and/or temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ), while the system is running, over a sufficiently long period to time,
• wherein results that are obtained in each case are compared with each other by the controller, in order to determine by the comparison a degradation of the system in function or effect,
• wherein the measurement values are scaled, in particular, by means of a mathematical model of the energy consumer (11, 12, 13) for purposes of comparison, or wherein other comparable measurements are used for comparison, when specified operating parameters have changed significantly in the meantime,
• wherein a control valve (19) with characteristic curves and being controlled by the controller (21) is used for open and/or closed loop control of the volumetric rate of flow (φ) in the primary circuit (26), and
• wherein a pressure differential (Δp) occurring at the control valve (19) is determined by the controller (21) from the measured volumetric flow rate (φ) in accordance with the characteristic curves of the control valve (19) and the valve position, and, if required, is used for controlling and/or monitoring purposes.

An adaptive variable flow Heating Ventilation Air-conditioning (HVAC) system (10), comprising:

• a primary circuit (26), which is traversed by the flow of an energy transporting medium,
• at least one energy consumer (11, 12, 13), which is connected to the primary circuit (26) by way of a supply line (14) and a return line (15),
• temperature sensors (16, 17) for determining the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) at the energy consumer (11, 12, 13) as well as at least one flow sensor (18) for determining the volumetric flow rate (φ) through the energy consumer (11, 12, 13), and
• a controller (21, 22) that is connected to the temperature and flow sensors (16, 17 and/or 18), wherein the controller (21, 22) receives and stores measurement values, which are outputted simultaneously by the temperature and flow sensors (16, 17 and/or 18), at different times,
• wherein a dependence of the flow of energy (E) on the volumetric flow rate (φ) is repeatedly determined empirically at varying time intervals by the controller,
• wherein, on the basis of the determined dependence, an upper limit value (Emax) of the flow of energy (E) is established, and said upper limit value is not exceeded while the HVAC system (10) is running,
• wherein a control valve (19) with characteristic curves and being controlled by the controller (21, 22) is used for open and/or closed loop control of the volumetric rate of flow (φ) in the primary circuit (26), and
• wherein a pressure differential (Δp) occurring at the control valve (19) is determined by the controller (21, 22) from the measured volumetric flow rate (φ) in accordance with the characteristic curves of the control valve (19) and the valve position, and, if required, is used for controlling and/or monitoring purposes.

An adaptive variable flow Heating Ventilation Air-conditioning (HVAC) system (10), comprising:

• a primary circuit (26), which is traversed by the flow of an energy transporting medium,
• at least one energy consumer (11, 12, 13), which is connected to the primary circuit (26) by way of a supply line (14) and a return line (15),
• temperature sensors (16, 17) for determining the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) at the energy consumer (11, 12, 13) as well as at least one flow sensor (18) for determining the volumetric flow rate (φ) through the energy consumer (11, 12, 13), and
• a controller (21, 22) that is connected to the temperature and flow sensors (16, 17 and/or 18), wherein the controller (21, 22) receives and stores measurement values, which are outputted simultaneously by the temperature and flow sensors (16, 17 and/or 18), at different times,
• wherein dependence of the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) is repeatedly determined empirically at varying time intervals by the controller, and
• wherein, on the basis of the determined dependence, a lower limit value (ΔTmin) of the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) is established,
• wherein said lower limit value is not undershot while the HVAC system (10) is running,
• wherein a control valve (19) with characteristic curves and being controlled by the controller (21, 22) is used for open and/or closed loop control of the volumetric rate of flow (φ) in the primary circuit (26), and
• wherein a pressure differential (Δp) occurring at the control valve (19) is determined by the controller (21, 22) from the measured volumetric flow rate (φ) in accordance with the characteristic curves of the control valve (19) and the valve position, and, if required, is used for controlling and/or monitoring purposes.

An adaptive variable flow Heating Ventilation Air-conditioning (HVAC) system (10), comprising:

• a primary circuit (26), which is traversed by the flow of an energy transporting medium,
• at least one energy consumer (11, 12, 13), which is connected to the primary circuit (26) by way of a supply line (14) and a return line (15),
• temperature sensors (16, 17) for determining the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) at the energy consumer (11, 12, 13) as well as at least one flow sensor (18) for determining the volumetric flow rate (φ) through the energy consumer (11, 12, 13), and
• a controller (21, 22) that is connected to the temperature and flow sensors (16, 17 and/or 18), wherein the controller (21, 22) receives and stores measurement values, which are outputted simultaneously by the temperature and flow sensors (16, 17 and/or 18), at different times,
• wherein dependence of the flow of energy (E) and/or the temperature differential ΔT between the supply temperature (Tv) and the return temperature (TR) on the volumetric flow rate (φ) is repeatedly determined empirically at varying time intervals by the controller,
• wherein results that are obtained in each case are compared with each other by the controller, in order to determine by means of the comparison a degradation of the system in function or effect,
• wherein a control valve (19) with characteristic curves and being controlled by the controller (21, 22) is used for open and/or closed loop control of the volumetric rate of flow (φ) in the primary circuit (26), and
• wherein a pressure differential (Δp) occurring at the control valve (19) is determined by the controller (21, 22) from the measured volumetric flow rate (φ) in accordance with the characteristic curves of the control valve (19) and the valve position, and, if required, is used for controlling and/or monitoring purposes.