Abstract: A heating, ventilation and air conditioning (HVAC) system includes a condenser (18) flowing a flow of refrigerant therethrough and to an output pipe (56) and a falling film evaporator (12) in flow communication with the condenser and having an evaporator input pipe (58) located vertically higher than the output pipe. A plurality of riser pipes (60) connect the output pipe to the evaporator input pipe. The flow of refrigerant flows through selected riser pipes of the plurality of riser pipes as required by a load on the HVAC system.

Abstract: A falling film evaporator includes an evaporator housing and a plurality of evaporator tubes disposed in the evaporator housing and arranged into one or more tube bundles, through which a volume of thermal energy transfer medium is flowed. A plurality of tube sheets support the plurality of evaporator tubes. A first wall member and a second wall member extend vertically at opposite lateral sides of the plurality of evaporator tubes. The first wall member and the second wall member define an inner vapor passage therebetween, define a first outer vapor passage between the first wall member and the evaporator housing, and define a second outer vapor passage between the second wall member and the evaporator housing. A first gap between a first wall member lower edge and the plurality of tube sheets is greater than second gap between a second wall member lower edge and the plurality of tube sheets.

Abstract: A method of lubricant management in a heating ventilation and air conditioning (HVAC) system includes flowing a volume of a compressor lubricant and refrigerant mixture from an evaporator into a lubricant still and stopping the flow of the compressor lubricant and refrigerant mixture into the lubricant still when the mixture fills the lubricant still to a selected level. Compressor lubricant is distilled from the mixture via a thermal energy exchange, and the distillation is stopped when a concentration of compressor lubricant in the lubricant still exceeds a predetermined concentration level. The distillate is urged from the lubricant still.

Abstract: A falling film evaporator (12) for a heating ventilation and cooling (HVAC) system includes a housing (52) and a plurality of evaporator tubes (26) positioned at least partially in the housing (52) through which a volume of thermal energy transfer medium is flowed. A distribution system (34) is located in the housing to distribute a flow of liquid refrigerant (20) over the plurality of evaporator tubes (26). The distribution system (34) includes a distribution vessel having a plurality of drip openings (38) to flow the liquid refrigerant onto the plurality of evaporator tubes (26), a feed pipe (42) to flow refrigerant into the distribution box (36), and one or more pressure regulators (58) in the distribution system, thereby regulating the flow of liquid refrigerant.

Abstract: A heating, ventilation and air-conditioning (HVAC) a falling film evaporator in flow communication with a condenser. The falling film evaporator includes a separator to separate vapor from liquid refrigerant and a plurality of evaporator tubes through which a volume of thermal energy transfer medium is flowed. A distribution system is operably connected to the separator to distribute a flow of liquid refrigerant over the plurality of evaporator tubes. A primary feed conduit delivers a flow of refrigerant to the separator, and at least one secondary feed conduit is in flow communication with the primary feed conduit. At least one auxiliary valve is located at the secondary feed conduit to regulate flow into the separator from the primary feed conduit. At least one sensor senses a level of a refrigerant pool in the evaporator. The sensor is operably connected to the at least one auxiliary valve to control operation thereof.

Abstract: A falling film evaporator for a heating ventilation and air conditioning (HVAC) system includes an evaporator housing and a plurality of evaporator tubes located in the evaporator housing and arranged into one or more tube bundles. A volume of thermal energy transfer medium is flowed through the plurality of evaporator tubes. One or more support sheets located along a length of the plurality of evaporator tubes to position and support the plurality of evaporator tubes in the housing, the one or more support sheets including one or more vapor flow passages to allow flow of vapor refrigerant along a length of the evaporator.

Abstract: A heating, ventilation and air conditioning (HVAC) system includes a condenser to condense a flow of refrigerant into a liquid state. The system further includes an economizer assembly having at least one separator chamber to separate liquid refrigerant from vapor refrigerant. The economizer assembly shares an upper common wall with at least a portion of the condenser and the flow of refrigerant from the condenser into the economizer assembly proceeds through a flow opening in the upper common wall. A falling film evaporator exchanges thermal energy between the liquid refrigerant and a medium flowed through a plurality of evaporator tubes in the evaporator.

Abstract: A heat exchanger adapted to transmit a first fluid through an interior, having a tubular body receptive of a second fluid, whereby heat transfer occurs between the fluids is provided, the tubular body extending longitudinally through the interior, having a non-circular cross-section, and being formed to define microchannels extending longitudinally along the tubular body through which the second fluid is transmitted.

Abstract: A shell and tube heat exchanger having a shell having an inner surface that defines a heat exchange zone, a refrigerant pool zone is arranged in the heat exchange zone, and a plurality of tube bundles are arranged in the heat exchange zone above the refrigerant pool zone. The tube bundles have first and second wall members that define a tube channel, and a plurality of tubes arranged in the tube channel. Each of the first and second wall members have a first end that extends to a second end that is spaced from the refrigerant pool zone. The plurality of tube bundles is spaced one from another so as to define one or more vapor passages. A refrigerant distributor is positioned above the tube channel. The refrigerant distributor delivers a refrigerant onto the plurality or tubes toward the refrigerant pool zone.

Abstract: A liquid distributor delivers a falling flow of the liquid to be distributed substantially uniformly along a longitudinal extent of the liquid distributor. The liquid distributor has a bottom wall including a longitudinally extending distribution plate having a plurality of laterally spaced and longitudinally extending channels. A shell and tube evaporator for chilling a working fluid incorporates the liquid distributor as a distributor of liquid onto the heat exchange tubes of a tube bundle disposed within an interior volume of the shell. Each channel is aligned with a respective column of the plurality of vertical columns of heat exchange tubes and is configured to deliver a falling flow of liquid refrigerant onto the respective tube column substantially uniformly along the longitudinal extent of the respective tube column.

Abstract: A heating, ventilation and air conditioning (HVAC) system includes a condenser (18) flowing a flow of refrigerant therethrough and to an output pipe (56) and a falling film evaporator (12) in flow communication with the condenser and having an evaporator input pipe (58) located vertically higher than the output pipe. A plurality of riser pipes (60) connect the output pipe to the evaporator input pipe. The flow of refrigerant flows through selected riser pipes of the plurality of riser pipes as required by a load on the HVAC system.

Abstract: A falling film evaporator includes an evaporator housing and a plurality of evaporator tubes disposed in the evaporator housing and arranged into one or more tube bundles, through which a volume of thermal energy transfer medium is flowed. A plurality of tube sheets support the plurality of evaporator tubes. A first wall member and a second wall member extend vertically at opposite lateral sides of the plurality of evaporator tubes. The first wall member and the second wall member defme an inner vapor passage therebetween, define a first outer vapor passage between the first wall member and the evaporator housing, and defme a second outer vapor passage between the second wall member and the evaporator housing. A first gap between a first wall member lower edge and the plurality of tube sheets is greater than second gap between a second wall member lower edge and the plurality of tube sheets.

Abstract: A method of lubricant management in a heating ventilation and air conditioning (HVAC) system includes flowing a volume of a compressor lubricant and refrigerant mixture from an evaporator into a lubricant still and stopping the flow of the compressor lubricant and refrigerant mixture into the lubricant still when the mixture fills the lubricant still to a selected level. Compressor lubricant is distilled from the mixture via a thermal energy exchange, and the distillation is stopped when a concentration of compressor lubricant in the lubricant still exceeds a predetermined concentration level. The distillate is urged from the lubricant still.

Abstract: A falling film evaporator (12) for a heating ventilation and cooling (HVAC) system includes a housing (52) and a plurality of evaporator tubes (26) positioned at least partially in the housing (52) through which a volume of thermal energy transfer medium is flowed. A distribution system (34) is located in the housing to distribute a flow of liquid refrigerant (20) over the plurality of evaporator tubes (26). The distribution system (34) includes a distribution vessel having a plurality of drip openings (38) to flow the liquid refrigerant onto the plurality of evaporator tubes (26), a feed pipe (42) to flow refrigerant into the distribution box (36), and one or more pressure regulators (58) in the distribution system, thereby regulating the flow of liquid refrigerant.

Abstract: A heating, ventilation and air-conditioning (HVAC) a falling film evaporator in flow communication with a condenser. The falling film evaporator includes a separator to separate vapor from liquid refrigerant and a plurality of evaporator tubes through which a volume of thermal energy transfer medium is flowed. A distribution system is operably connected to the separator to distribute a flow of liquid refrigerant over the plurality of evaporator tubes. A primary feed conduit delivers a flow of refrigerant to the separator, and at least one secondary feed conduit is in flow communication with the primary feed conduit. At least one auxiliary valve is located at the secondary feed conduit to regulate flow into the separator from the primary feed conduit. At least one sensor senses a level of a refrigerant pool in the evaporator. The sensor is operably connected to the at least one auxiliary valve to control operation thereof.

Abstract: A heating, ventilation and air conditioning (HVAC) system includes a condenser to condense a flow of refrigerant into a liquid state. The system further includes an economizer assembly having at least one separator chamber to separate liquid refrigerant from vapor refrigerant. The economizer assembly shares an upper common wall with at least a portion of the condenser and the flow of refrigerant from the condenser into the economizer assembly proceeds through a flow opening in the upper common wall. A falling film evaporator exchanges thermal energy between the liquid refrigerant and a medium flowed through a plurality of evaporator tubes in the evaporator.

Abstract: A heat exchange tube for a refrigerant-flooded evaporator includes a tube body and a plurality of channels for conveying a cooling medium therethrough located in the tube body. One or more outer wall textural elements are included at the outer wall of the tube body to improve thermal energy transfer between the cooling medium and a volume of boiling refrigerant. A method of forming a heat exchange tube for a refrigerant-flooded evaporator includes urging a billet into an extrusion section and forming the billet into two tube halves including an outer wall and an inner wall having a plurality of channel halves. A textural element is formed at one or more of the outer wall and the inner wall via one or more rotating dies, and the two tube halves are joined to form the heat exchange tube.

Abstract: A liquid distributor delivers a falling flow of the liquid to be distributed substantially uniformly along a longitudinal extent of the liquid distributor. The liquid distributor has a bottom wall including a longitudinally extending distribution plate having a plurality of laterally spaced and longitudinally extending channels. A shell and tube evaporator for chilling a working fluid incorporates the liquid distributor as a distributor of liquid onto the heat exchange tubes of a tube bundle disposed within an interior volume of the shell. Each channel is aligned with a respective column of the plurality of vertical columns of heat exchange tubes and is configured to deliver a falling flow of liquid refrigerant onto the respective tube column substantially uniformly along the longitudinal extent of the respective tube column.

Abstract: A shell and tube heat exchanger includes a shell having an inner surface that defines a heat exchange zone, a refrigerant pool zone is arranged in the heat exchange zone, and a plurality of tube bundles are arranged in the heat exchange zone above the refrigerant pool zone. The tube bundles include first and second wall members that define a tube channel, and a plurality of tubes arranged in the tube channel. Each of the first and second wall members have a first end that extends to a second end that is spaced from the refrigerant pool zone. The plurality of tube bundles is spaced one from another so as to define one or more vapor passages. A refrigerant distributor is positioned above the tube channel. The refrigerant distributor is configured and disposed to deliver a refrigerant onto the plurality or tubes toward the refrigerant pool zone.

Abstract: A falling film evaporator for a heating ventilation and air conditioning (HVAC) system includes an evaporator housing and a plurality of evaporator tubes located in the evaporator housing and arranged into one or more tube bundles. A volume of thermal energy transfer medium is flowed through the plurality of evaporator tubes. One or more support sheets located along a length of the plurality of evaporator tubes to position and support the plurality of evaporator tubes in the housing, the one or more support sheets including one or more vapor flow passages to allow flow of vapor refrigerant along a length of the evaporator.