Abstract: A heating, ventilation, and air conditioning (HVAC) system includes an enclosure and an evaporator coil disposed within the enclosure. The HVAC system also includes a pivot member coupled between an edge portion of the evaporator coil and the enclosure. The pivot member is configured to enable the evaporator coil to pivot relative to the enclosure to adjust an operating angle of the evaporator coil during operation of the HVAC system. Additionally, the HVAC system includes an actuator configured to enable pivoting of the evaporator coil to a target operating angle based on an operating parameter input.

Abstract: A combined suction header and accumulator for a refrigeration system is described that may protect a compressor from refrigerant liquid entering the compressor while reducing superheat used to evaporate the refrigerant. The combined suction header and accumulator unit for a refrigeration system includes a suction header coupled to an exit side of an evaporator. The suction header includes a main body and receives a flow of refrigerant from the evaporator. The flow of refrigerant includes a liquid portion and a vapor portion. The combined suction header and accumulator unit includes a liquid accumulator disposed within the main body of the suction header. The liquid accumulator blocks the liquid portion of the flow of refrigerant from exiting the main body.

Abstract: A refrigerant leak management system includes a sleeve member having an inner surface, the sleeve member configured to be disposed over an outer surface of a length of a refrigerant conduit such that a gap is defined between the inner surface of the sleeve member and the outer surface of the refrigerant conduit. The refrigerant leak management system also includes a fluid moving device configured to fluidly couple to the gap and configured to maintain a sub-barometric pressure within the gap, and a sensor fluidly coupled to the gap and configured to detect a concentration of a leaked refrigerant in the gap.

Abstract: The present disclosure relates to a heating ventilation and air conditioning (HVAC) system. The system includes a primary heat transfer loop configured to be disposed at least partially outside of a building, and the primary heat transfer loop includes a heat exchanger, a compressor configured to compress a refrigerant, where the refrigerant is reactive, a condenser configured to receive and condense the refrigerant, and an expansion device configured to reduce a temperature of the refrigerant. The system further includes a secondary heat transfer loop configured to circulate a two-phase fluid at least partially inside the building, wherein the two-phase fluid is less reactive than the refrigerant.

Abstract: A refrigerant leak management system of a HVAC unit includes a sensor configured to detect a refrigerant in an interior of an air handling enclosure. The refrigerant leak management system includes a plurality of airflow management assemblies configured to fluidly isolate the interior of the air handling enclosure in a closed configuration. The plurality of airflow management assemblies includes a return inlet assembly, a supply outlet assembly, and a purge exhaust outlet assembly. The refrigerant leak management system includes a controller configured to actuate the purge exhaust outlet assembly based on detection of the refrigerant by the sensor such that the purge exhaust outlet assembly transitions from a closed position of the purge exhaust outlet assembly to an open position of the purge exhaust outlet assembly that opens the interior of the air handling enclosure to an external environment.

Abstract: A heat exchanger includes a frame and a plurality of coil passes disposed within the frame. The plurality of coil passes is configured to direct a flow of a refrigerant therethrough to transfer heat with an air flow passing over the heat exchanger. The plurality of coil passes include a U-bend disposed between first and second linear portions of the plurality of coil passes to redirect the refrigerant from a first longitudinal end of the heat exchanger to a second longitudinal end of the heat exchanger. Additionally, a first plurality of fins is disposed on an outer surface the U-bend.

Abstract: The present disclosure relates to a heat exchanger coil prototyping system. The heat exchanger coil prototyping system includes a heat exchanger coil with a first conduit and a second conduit that carry a refrigerant. The first conduit includes a first open end and a second open end. The second conduit includes a third open end and a fourth open end. A fin couples to the first conduit and the second conduit. A quick release connector system also couples to the first and second conduits. The quick release connector system includes a first quick release connector assembly that couples to the first open end of the first conduit and to the third open end of the second conduit to route the refrigerant between the first and second conduits. A second quick release connector assembly couples to the second conduit.

Abstract: A heating, ventilating, and air conditioning (HVAC) system includes a refrigerant loop having a compressor, where the compressor is configured to circulate a refrigerant through the refrigerant loop, a first heat exchanger disposed along the refrigerant loop, where the first heat exchanger is configured to place the refrigerant in a first heat exchange relationship with a working fluid, and an air handling unit having a second heat exchanger, where the second heat exchanger is configured to place the working fluid in a second heat exchange relationship with an airflow, and where the air handling unit is isolated from the first heat exchanger to reduce or eliminate mixing of refrigerant with the airflow.

Abstract: A heating, ventilation, and air conditioning (HVAC) system includes an enclosure and an evaporator coil disposed within the enclosure. The HVAC system also includes a pivot member coupled between an edge portion of the evaporator coil and the enclosure. The pivot member is configured to enable the evaporator coil to pivot relative to the enclosure to adjust an operating angle of the evaporator coil during operation of the HVAC system. Additionally, the HVAC system includes an actuator configured to enable pivoting of the evaporator coil to a target operating angle based on an operating parameter input.

Abstract: A combined suction header and accumulator for a refrigeration system is described that may protect a compressor from refrigerant liquid entering the compressor while reducing superheat used to evaporate the refrigerant. The combined suction header and accumulator unit for a refrigeration system includes a suction header coupled to an exit side of an evaporator. The suction header includes a main body and receives a flow of refrigerant from the evaporator. The flow of refrigerant includes a liquid portion and a vapor portion. The combined suction header and accumulator unit includes a liquid accumulator disposed within the main body of the suction header. The liquid accumulator blocks the liquid portion of the flow of refrigerant from exiting the main body.

Abstract: A cooling system includes an expansion valve configured to exert a first pressure drop on refrigerant circulated through the cooling system. The cooling system also includes a plurality of capillary expansion tubes fluidly coupled in parallel to an output of the expansion valve and configured to exert a second pressure drop on the refrigerant circulated through the cooling system. The cooling system also includes a controller communicatively coupled to the expansion valve, wherein the controller is configured to control magnitude of the first pressure drop by instructing the expansion valve to adjust the valve position based at least in part on refrigerant mass flow expected to be supplied to the expansion valve to facilitate substantially uniformly distributing the refrigerant mass flow between each of the plurality capillary expansion tubes.

Abstract: In one embodiment, a cooling system includes an evaporator, which further includes an evaporator tube, a first mechanical wave emitter, and a control system communicatively coupled to the first mechanical wave emitter. The cooling system is configured to circulate refrigerant through the evaporator tube to facilitate heat exchange between the refrigerant and fluid surrounding the evaporator tube. The first mechanical wave emitter is configured to output first mechanical waves to the evaporator tube, and the control system is configured to instruct the first mechanical wave emitter to output the first mechanical waves to enhance nucleation of the refrigerant in the evaporator tube.

Abstract: A heating, ventilation, and air conditioning (HVAC) unit is provided. The HVAC unit includes a cabinet that has a boundary that defines an interior volume, and HVAC components are situated within the interior volume. Additionally, the HVAC unit includes a panel that forms part of the boundary, and the panel includes an aerogel material.

Abstract: A cooling system includes a subcooling heat exchange assembly, which controls magnitude of subcooling of refrigerant circulated through the cooling system. The subcooling heat exchange assembly includes a first fluid line fluidly coupled to an output of a condenser to enable a first portion of the refrigerant output from the condenser to flow through the first fluid line; a second fluid line fluidly coupled to the output of the condenser to enable a second portion of the refrigerant output from the condenser to flow through the second fluid line; and an expansion valve disposed along the second fluid line, in which the expansion valve exerts a first pressure drop on the second portion of the refrigerant that facilitates extracting heat from the first portion of the refrigerant flowing through the first fluid line using the second portion of the refrigerant flowing through the second fluid line when valve position of the expansion valve is greater than a threshold position.

Abstract: A condenser arrangement for control of condenser temperature and condenser pressure. The condenser arrangement includes a condenser coil and a plurality of fans disposed adjacent to the condenser coil. The plurality of fans are arranged and disposed to circulate air through the condenser coil. At least one baffle is positioned between adjacent fans of the plurality of fans and forms a plurality of channels extending from a surface of the condenser coil. The channels include a variable flow channel having a plurality of adjacent fans of the plurality of fans. The condenser arrangement also includes a control system to control operation of the plurality of fans. The control system is configured to independently control each fan of the plurality of fans in response to a sensed condition.

Abstract: A fin for a heat exchanger coil assembly and a method of manufacturing the fin is provided. The fin includes a heat transfer enhancement pattern which appears sinusoidal in shape. The base wavy pattern of the enhancement pattern includes two wavelengths within each tube row and includes seven discrete segments. Six of the seven segments are circular arc segments. The seventh segment comprises two linear segments which form a condensate channel. The segments are arranged in a particular order at specific distances offset (above and below) from a leading edge nominal air streamline (LENAS) by a fraction of a nominal fin pitch Pf. The LENAS is related to the “normal” base wavy pattern used in other fins.

Abstract: A fin for a heat exchanger coil assembly and a method of manufacturing the fin is provided. The fin includes a heat transfer enhancement pattern which appears sinusoidal in shape. The base wavy pattern of the enhancement pattern includes two wavelengths within each tube row and includes seven discrete segments. Six of the seven segments are circular arc segments. The seventh segment comprises two linear segments which form a condensate channel. The segments are arranged in a particular order at specific distances offset (above and below) from a leading edge nominal air streamline (LENAS) by a fraction of a nominal fin pitch Pf. The LENAS is related to the “normal” base wavy pattern used in other fins.

Abstract: A chiller system includes a refrigerant loop, the refrigerant loop further including a compressor, an air-cooled condenser arrangement and an evaporator arrangement connected in a first closed refrigerant loop. A motor is connected to the compressor to drive the compressor, a drive is connected to the motor to power the motor and a power/control panel controls the refrigerant loop. The power/control panel and the condenser arrangement are connected in a second closed coolant loop. The second closed coolant loop provides cooling to the enclosure and/or components within the enclosure disposed on a chill plate. Condensation is substantially prevented from forming inside the enclosure, despite the enclosure lacking a humidity control device.

Abstract: A system and method are provided for variable speed operation of a screw compressor to obtain increased capacity and efficiency. The screw compressor is connected to an induction motor driven by a variable speed drive, wherein the screw compressor has a variable output capacity that is dependent on the output speed of the motor. To obtain increased capacity and efficiency, the screw compressor is operated at a speed greater than the screw compressor's rated speed and does not include a slide valve. The maximum operating speed of the screw compressor, which speed is greater than the rated speed, is related to the maximum operating speed of the motor when operated at a voltage and frequency provided by the variable speed drive that is greater than the motor's rated voltage and frequency in a constant flux or constant volts/Hz mode.

Abstract: A fin for a heat exchanger coil assembly and a method of manufacturing the fin is provided. The fin includes a heat transfer enhancement pattern which appears sinusoidal in shape. The base wavy pattern of the enhancement pattern includes two wavelengths within each tube row and includes seven discrete segments. Six of the seven segments are circular arc segments. The seventh segment comprises two linear segments which form a condensate channel. The segments are arranged in a particular order at specific distances offset (above and below) from a leading edge nominal air streamline (LENAS) by a fraction of a nominal fin pitch Pf. The LENAS is related to the “normal” base wavy pattern used in other fins.