Abstract: A heating, ventilation, and air conditioning (HVAC) system includes a primary heat transfer circuit having a first heat exchanger fluidly coupled to an ambient environment and a compressor fluidly coupled to the first heat exchanger and configured to circulate a refrigerant through the primary heat transfer circuit. The HVAC system also includes a secondary heat transfer circuit having a second heat exchanger fluidly coupled to a thermal load and a pump fluidly coupled to the second heat exchanger and configured to circulate a heat transfer fluid through the secondary heat transfer circuit, where the heat transfer fluid is a non-volatile or inert fluid.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) system that includes a refrigerant circuit and a sensor configured to measure a refrigerant concentration external to the refrigeration circuit. The HVAC system also includes a controller that is communicatively coupled to the sensor and to an economizer. The controller is configured to control a flow of environmental air into the HVAC system. The controller is further configured to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the sensor measures the refrigerant concentration above a predetermined threshold concentration.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) system that includes a refrigerant circuit and a sensor configured to measure a refrigerant concentration external to the refrigeration circuit. The HVAC system also includes a controller that is communicatively coupled to the sensor and to an economizer. The controller is configured to control a flow of environmental air into the HVAC system. The controller is further configured to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the sensor measures the refrigerant concentration above a predetermined threshold concentration.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) system that includes a refrigerant circuit and a sensor configured to measure a refrigerant concentration external to the refrigeration circuit. The HVAC system also includes a controller that is communicatively coupled to the sensor and to an economizer. The controller is configured to control a flow of environmental air into the HVAC system. The controller is further configured to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the sensor measures the refrigerant concentration above a predetermined threshold concentration.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) unit including a first refrigeration circuit having a first compressor and a first condenser, a second refrigeration circuit having a second compressor and a second condenser, a first fan configured to generate airflow over the first condenser, a second fan configured to generate airflow over the second condenser, an evaporator common to the first refrigeration circuit and the second refrigeration circuit, and a controller configured to control operation of the HVAC unit according to an active staging operation of a plurality of staging operations, wherein the plurality of staging operations comprises at least three stages of operation in which each of the first and second compressors individually operates in a selection of at least two compression settings and each of the first and second fans individually operates in a selection of at least two speed settings.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) system that includes a refrigerant circuit and a sensor configured to measure a refrigerant concentration external to the refrigeration circuit. The HVAC system also includes a controller that is communicatively coupled to the sensor and to an economizer. The controller is configured to control a flow of environmental air into the HVAC system. The controller is further configured to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the sensor measures the refrigerant concentration above a predetermined threshold concentration.

Abstract: The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) unit including a first refrigeration circuit having a first compressor and a first condenser, a second refrigeration circuit having a second compressor and a second condenser, a first fan configured to generate airflow over the first condenser, a second fan configured to generate airflow over the second condenser, an evaporator common to the first refrigeration circuit and the second refrigeration circuit, and a controller configured to control operation of the HVAC unit according to an active staging operation of a plurality of staging operations, wherein the plurality of staging operations comprises at least three stages of operation in which each of the first and second compressors individually operates in a selection of at least two compression settings and each of the first and second fans individually operates in a selection of at least two speed settings.