Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: An HVACR system includes first and second compressors arranged in parallel, a condenser, an expansion device, an evaporator, and a lubricant separator fluidly connected. The first compressor includes a first lubricant sump and a first suction inlet. The second compressor includes a second lubricant sump and a second suction inlet. The lubricant separator is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to at least one of the first and second lubricant sumps. A second of the two fluid outlets is fluidly connected to the first and second suction inlets. The second fluid outlet includes a nozzle disposed within a flow passage of the lubricant separator such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: A system includes first and second compressors arranged in parallel, a condenser, expansion device, evaporator, and flow control device fluidly connected. The first compressor includes a first lubricant sump and the second compressor including a second lubricant sump. A lubricant transfer conduit fluidly connects the first lubricant sump and the second lubricant sump. The flow control device is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to the first compressor, a second of the two fluid outlets is fluidly connected to the second compressor. The second fluid outlet includes a nozzle disposed within a flow passage of the flow control device such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: This disclosure is directed to systems and methods for determining airflow in a heating, ventilation, air conditioning and refrigeration (HVACR) system to reduce overall power consumption. Methods include receiving efficiency data for one or more compressors of the HVACR system, receiving airflow power consumption data, determining, using a processor, a flow rate based on the efficiency data for the one or more compressors and the airflow power consumption data, and when the HVACR system is in a partial load condition and at least one of the one or more compressors are in operation, operating the HVACR system at the determined flow rate. Systems include one or more compressors, one or more blower fans, and a processor configured to determine an airflow rate for the one or more blower fans based on efficiency data for the one or more compressors and airflow power consumption data.

Abstract: An HVACR system includes first and second compressors arranged in parallel, a condenser, an expansion device, an evaporator, and a lubricant separator fluidly connected. The first compressor includes a first lubricant sump and a first suction inlet. The second compressor includes a second lubricant sump and a second suction inlet. The lubricant separator is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to at least one of the first and second lubricant sumps. A second of the two fluid outlets is fluidly connected to the first and second suction inlets. The second fluid outlet includes a nozzle disposed within a flow passage of the lubricant separator such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: This disclosure is directed to systems and methods for determining airflow in a heating, ventilation, air conditioning and refrigeration (HVACR) system to reduce overall power consumption. Methods include receiving efficiency data for one or more compressors of the HVACR system, receiving airflow power consumption data, determining, using a processor, a flow rate based on the efficiency data for the one or more compressors and the airflow power consumption data, and when the HVACR system is in a partial load condition and at least one of the one or more compressors are in operation, operating the HVACR system at the determined flow rate. Systems include one or more compressors, one or more blower fans, and a processor configured to determine an airflow rate for the one or more blower fans based on efficiency data for the one or more compressors and airflow power consumption data.

Abstract: A system includes first and second compressors arranged in parallel, a condenser, expansion device, evaporator, and flow control device fluidly connected. The first compressor includes a first lubricant sump and the second compressor including a second lubricant sump. A lubricant transfer conduit fluidly connects the first lubricant sump and the second lubricant sump. The flow control device is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to the first compressor, a second of the two fluid outlets is fluidly connected to the second compressor. The second fluid outlet includes a nozzle disposed within a flow passage of the flow control device such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: A system includes first and second compressors arranged in parallel, a condenser, expansion device, evaporator, and flow control device fluidly connected. The first compressor includes a first lubricant sump and the second compressor including a second lubricant sump. A lubricant transfer conduit fluidly connects the first lubricant sump and the second lubricant sump. The flow control device is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to the first compressor, a second of the two fluid outlets is fluidly connected to the second compressor. The second fluid outlet includes a nozzle disposed within a flow passage of the flow control device such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: A system includes first and second compressors arranged in parallel, a condenser, expansion device, evaporator, and flow control device fluidly connected. The first compressor includes a first lubricant sump and the second compressor including a second lubricant sump. A lubricant transfer conduit fluidly connects the first lubricant sump and the second lubricant sump. The flow control device is disposed between the evaporator and the first and second compressors, and includes a fluid inlet and two fluid outlets. A first of the two fluid outlets is fluidly connected to the first compressor, a second of the two fluid outlets is fluidly connected to the second compressor. The second fluid outlet includes a nozzle disposed within a flow passage of the flow control device such that a space is maintained between an outer surface of the nozzle and an inner surface of the flow passage.

Abstract: A refrigerant system for cooling a comfort zone is selectively operable in a cooling-only mode and a reheat mode. The system operates in the cooling mode to meet sensible and latent cooling demands of a room or area in a building when the room temperature is appreciably above a target temperature. The reheat mode is for addressing the latent cooling or dehumidifying demand when the room temperature is near or below the target temperature. In some embodiments, a generally inactive condenser stores excess refrigerant during the reheat mode, thereby avoiding the need for a separate liquid refrigerant receiver. To maintain a desired level of subcooling in the reheat coil, refrigerant can be transferred accordingly between the inactive condenser and the reheat coil. In some embodiments, the system's evaporator and reheat coil can be connected in a series or parallel flow relationship.

Abstract: A refrigerant system for cooling a comfort zone is selectively operable in a cooling-only mode and a reheat mode. The system operates in the cooling mode to meet sensible and latent cooling demands of a room or area in a building when the room temperature is appreciably above a target temperature. The reheat mode is for addressing the latent cooling or dehumidifying demand when the room temperature is near or below the target temperature. In some embodiments, a generally inactive condenser stores excess refrigerant during the reheat mode, thereby avoiding the need for a separate liquid refrigerant receiver. To maintain a desired level of subcooling in the reheat coil, refrigerant can be transferred accordingly between the inactive condenser and the reheat coil. In some embodiments, the system's evaporator and reheat coil can be connected in a series or parallel flow relationship.