Abstract: For monitoring and controlling an HVAC system which comprises one or more fluid transportation systems with a plurality of parallel zones, a plurality of operating variables of the fluid transportation systems are received (S1) from devices of the HVAC system. Temporal courses are determined (S3) for the operating variables. Interdependencies are determined (S4) between the temporal courses of the operating variables. Depending on the interdependencies, the operating variables and their associated devices are grouped (S5) into different sets which each relates to a different section of the HVAC system and includes the related operating variables and associated devices. The sets are used (S6) to control the devices of a particular section of the HVAC system and/or to generate a fault detection message regarding one or more of the devices of the particular section of the HVAC system.

Abstract: A method for determining antifreeze content in a fluid of a heating, ventilation, and air conditioning (HVAC) system includes receiving, in a processor, measurement data of the fluid, the measurement data comprising a measured temperature of the fluid and a measured speed of sound in the fluid, calculating, in the processor, for each of a plurality of antifreeze concentration values a fitting parameter, using the measurement data and one or more of previous measurement data or previous antifreeze concentration data, and determining, in the processor, an antifreeze concentration in the fluid by selecting the antifreeze concentration value with an optimal fitting parameter.

Abstract: For monitoring an HVAC system (1), HVAC data reporting messages are received and stored in a cloud-based computer system (4). Each HVAC data reporting message includes one or more operation data values included by an HVAC controller (22) of the HVAC system (1). The cloud-based computer system (4) generates (S73) remote diagnoses for a particular HVAC device, using a plurality of HVAC reporting messages received from a plurality of the HVAC controllers (22) from one or more HVAC systems (1). Each remote diagnosis is generated (S73) by using more than one operational data value, included in HVAC reporting messages received (S71) received from HVAC controllers (22) of more than one HVAC systems (1) and/or from at least two different types of operational data values. A diagnosis message which includes a remote diagnosis is transmitted to a diagnosis processing system for the particular HVAC device.

Abstract: 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.

Abstract: For monitoring and controlling an HVAC system which comprises one or more fluid transportation systems with a plurality of parallel zones, a plurality of operating variables of the fluid transportation systems are received (S1) from devices of the HVAC system. Temporal courses are determined (S3) for the operating variables. Interdependencies are determined (S4) between the temporal courses of the operating variables. Depending on the interdependencies, the operating variables and their associated devices are grouped (S5) into different sets which each relates to a different section of the HVAC system and includes the related operating variables and associated devices. The sets are used (S6) to control the devices of a particular section of the HVAC system and/or to generate a fault detection message regarding one or more of the devices of the particular section of the HVAC system.

Abstract: For controlling energy transfer (Q) of a thermal energy exchanger of an HVAC system, a control system determines flow-dependent model parameters (M) for modelling performance of the thermal energy exchanger, using a plurality of measurement data sets, each measurement data set including for a respective measurement time a value of a measured flow of fluid (?act), a value of a measured supply temperature (Tsup) of the fluid, and a value of the measured return temperature (Tret) of the fluid. The control system calculates an estimated energy transfer (Qest) of the thermal energy exchanger, using the flow-dependent model parameters (M), and controls (S4) the energy transfer (Q) of the thermal energy exchanger by regulating (S5) the flow of fluid (?) through the thermal energy exchanger, using the estimated energy transfer (Qest).

Abstract: A method, system (100), and a computer program product comprising a non-transient computer-readable medium (190) having stored thereon computer program code configured to control one or more processors (180) of a computer (170) for operating an HVAC installation (200, 300), wherein a set of enthalpies (H1,i, H2,i, H1,o, H2,o) and flow rates (?1, ?2) as variables of the HVAC installation (200, 300) is monitored and used for controlling the operation of said HVAC installation (200, 300), comprising the steps of: (a) dividing said set of enthalpies (H1,i, H2,i, H1,o, H2,o) and flow rates (?1, ?2) into a first and second subset; (b) measuring each variable of said first subset with a related sensor (110, 120) arranged in said HVAC installation (200, 300); and (c) determining the variables of said second subset from the measured variables of said first subset by using a mathematical and/or empirical relationship between the variables of said first and second subset.

Abstract: A fluid transportation network (1) comprises a plurality of parallel zones (Z1, Z2), fed by a common supply line (L), with a regulating zone valve (V1, V2) in each zone (Z1, Z2) for regulating a flow of fluid (?1, ?2) through the respective zone (Z1, Z2). A processing unit (RE) receives valve positions (pos1, pos2) of the regulating zone valves (V1, V2) and determines and sets an adjusted valve position for a line valve (VE) arranged in the supply line (L), depending on the valve positions (pos1, pos2) of the regulating zone valves (V1, V2). A processing unit (RE) further receives a measurement of a total flow of fluid (?tot) through the supply line (L) and determines and sets adjusted valve positions for the regulating zone valves (V1, V2), depending on the measurement of the total flow of fluid (?tot) through the supply line (L).

Abstract: For controlling opening (B2) of a valve in an HVAC system to regulate the fluid flow through a thermal energy exchanger and adjust power transfer of the thermal energy exchanger, a control system sets (S6) a control signal for the valve to different setpoints and records (S1) a plurality of data points. Each data point includes for a certain setpoint operating data values related to the power transfer effectuated by the thermal energy exchanger with the control signal set to the certain setpoint. The control system determines (S2) a fitting curve for the data points and determines (S3) a transformation which transforms the fitting curve into a transformed curve having a given target shape. The control system controls (B2) the opening of the valve by transforming (S5) the setpoint to a transformed setpoint, using the transformation, and setting (S6) the control signal for the valve to the transformed setpoint.

Abstract: A hydronic system (HS) that comprises at least one hydronic circuit (HC) and a control (CT) for controlling the operation of said at least one hydronic circuit (HC) via a control path (CP), whereby said control (CT) comprises a feed forward controller (FFC). Operation of the system is improved by the hydronic system (HS) further comprising a control improvement path (CIP) running from the at least one hydronic circuit (HC) to the control (CT). Due to the control improvement path (CIP), the control (CT) can be improved in the case of the hydronic system (HS) becoming instable and/or showing poor system control.

Abstract: A method, system (100), and a computer program product comprising a non-transient computer-readable medium (190) having stored thereon computer program code configured to control one or more processors (180) of a computer (170) for operating an HVAC installation (200, 300), wherein a set of enthalpies (H1,i, H2,i, H1,o, H2,o) and flow rates (?1, ?2) as variables of the HVAC installation (200, 300) is monitored and used for controlling the operation of said HVAC installation (200, 300), comprising the steps of: (a) dividing said set of enthalpies (H1,i, H2,i, H1,o, H2,o) and flow rates (?1, ?2) into a first and second subset; (b) measuring each variable of said first subset with a lo related sensor (110, 120) arranged in said HVAC installation (200, 300); and (c) determining the variables of said second subset from the measured variables of said first subset by using a mathematical and/or empirical relationship between the variables of said first and second subset.

Abstract: For operating a thermal energy exchanger (1) for exchanging thermal energy between a thermal transfer fluid and air, a plurality of measurement data sets are recorded in a control system (40). The measurement data sets include for a different point in time data values which define a normalized energy transfer that represents the thermal energy transferred in the thermal energy exchanger (1) normalized by one or more normalization variables. The control system (40) calculates for each of the measurement data sets a normalized data point defined by the normalized energy transfer. The control system (40) further determines for the thermal energy exchanger (1) a characteristic energy transfer curve which fits the normalized data points. Normalizing the energy transfer makes it possible to operate the thermal energy exchanger (1) more efficiently over a wider range of changing conditions, as saturation can be prevented using more appropriate fixed or variable thresholds.

Abstract: A hydronic system (HS) that comprises at least one hydronic circuit (HC) and a control (CT) for controlling the operation of said at least one hydronic circuit (HC) via a control path (CP), whereby said control (CT) comprises a feed forward controller (FFC). Operation of the system is improved by the hydronic system (HS) further comprising a control improvement path (CIP) running from the at least one hydronic circuit (HC) to the control (CT). Due to the control improvement path (CIP), the control (CT) can be improved in the case of the hydronic system (HS) becoming instable and/or showing poor system control.

Abstract: For monitoring an HVAC system (1), HVAC data reporting messages are received and stored in a cloud-based computer system (4). Each HVAC data reporting message includes one or more operation data values included by an HVAC controller (22) of the HVAC system (1). The cloud-based computer system (4) generates (S73) remote diagnoses for a particular HVAC device, using a plurality of HVAC reporting messages received from a plurality of the HVAC controllers (22) from one or more HVAC systems (1). Each remote diagnosis is generated (S73) by using more than one operational data value, included in HVAC reporting messages received (S71) received from HVAC controllers (22) of more than one HVAC systems (1) and/or from at least two different types of operational data values. A diagnosis message which includes a remote diagnosis is transmitted to a diagnosis processing system for the particular HVAC device.

Abstract: A fluid transportation network (1) comprises a plurality of parallel zones (Z1, Z2), fed by a common supply line (L), with a regulating zone valve (V1, V2) in each zone (Z1, Z2) for regulating a flow of fluid (?1, ?2) through the respective zone (Z1, Z2). A processing unit (RE) receives valve positions (pos1, pos2) of the regulating zone valves (V1, V2) and determines and sets an adjusted valve position for a line valve (VE) arranged in the supply line (L), depending on the valve positions (pos1, pos2) of the regulating zone valves (V1, V2). A processing unit (RE) further receives a measurement of a total flow of fluid (?tot) through the supply line (L) and determines and sets adjusted valve positions for the regulating zone valves (V1, V2), depending on the measurement of the total flow of fluid (?tot) through the supply line (L).

Abstract: For operating a thermal energy exchanger (1) for exchanging thermal energy between a thermal transfer fluid and air, a plurality of measurement data sets are recorded in a control system (40). The measurement data sets include for a different point in time data values which define a normalized energy transfer that represents the thermal energy transferred in the thermal energy exchanger (1) normalized by one or more normalization variables. The control system (40) calculates for each of the measurement data sets a normalized data point defined by the normalized energy transfer. The control system (40) further determines for the thermal energy exchanger (1) a characteristic energy transfer curve which fits the normalized data points. Normalizing the energy transfer makes it possible to operate the thermal energy exchanger (1) more efficiently over a wider range of changing conditions, as saturation can be prevented using more appropriate fixed or variable thresholds.

Abstract: For controlling the opening of a valve (10) in an HVAC system (100) to regulate the flow ? of a fluid through a thermal energy exchanger (2) of the HVAC system (100) and adjust the amount of energy E exchanged by the thermal energy exchanger (2), determined are the flow ? through a valve (10) and the temperature difference ?T=Tin?Tout between the supply temperature Tin of the fluid entering the thermal energy exchanger (2) and the return temperature Tout of the fluid exiting the thermal energy exchanger (2). The opening of the valve (10) is controlled depending on the flow ? and the temperature difference ?T. For example, the opening of the valve (10) is controlled depending on a control criterion c=ƒ(?,?T), calculated from the flow ? and the temperature difference ?T.

Abstract: A hydraulic network (1) having plural parallel zones (Z1, Z2) with a regulating valve (V1, V2) in each zone for regulating a flow of fluid (?1, ?2) through respective zones. Characteristic parameters of the hydraulic network (1) include static flow capacity values (Kex,a, Kex,b) of the zones. Measurement data sets are recorded which include a determined value of a hydraulic system variable of the hydraulic network (1), e.g. the total flow (?tot) or the system pressure (?P), and valve positions of the regulating valves (V1, V2) set for the determined value of the hydraulic system variable. The characteristic parameters are calculated from plural measurement data sets, by grouping related measurement data sets, which include the same value of the hydraulic system variable but different valve positions, and by using the flow capacity (Kvalve,a, Kvalve,b) of the regulating valves (V1, V2) at the valve positions included in the data sets.

Abstract: A hydraulic network (1) having plural parallel zones (Z1, Z2) with a regulating valve (V1, V2) in each zone for regulating a flow of fluid (?1, ?2) through respective zones. Characteristic parameters of the hydraulic network (1) include static flow capacity values (Kex,a, Kex,b) of the zones. Measurement data sets are recorded which include a determined value of a hydraulic system variable of the hydraulic network (1), e.g. the total flow (?tot) or the system pressure (?P), and valve positions of the regulating valves (V1, V2) set for the determined value of the hydraulic system variable. The characteristic parameters are calculated from plural measurement data sets, by grouping related measurement data sets, which include the same value of the hydraulic system variable but different valve positions, and by using the flow capacity (Kvalve,a, Kvalve,b) of the regulating valves (V1, V2) at the valve positions included in the data sets.

Abstract: For controlling the opening of a valve (10) in an HVAC system (100) to regulate the flow ? of a fluid through a thermal energy exchanger (2) of the HVAC system (100) and adjust the amount of energy E exchanged by the thermal energy exchanger (2), determined are the flow ? through a valve (10) and the temperature difference ?T=Tin?Tout between the supply temperature Tin of the fluid entering the thermal energy exchanger (2) and the return temperature Tout of the fluid exiting the thermal energy exchanger (2). The opening of the valve (10) is controlled depending on the flow ? and the temperature difference ?T. For example, the opening of the valve (10) is controlled depending on a control criterion c=f(?,?T), calculated from the flow ? and the temperature difference ?T.