Patent Publication Number: US-11656003-B2

Title: Climate-control system having valve assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/816,626, filed on Mar. 11, 2019. The entire disclosure of the above application is incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to a climate-control system having a valve assembly. 
     BACKGROUND 
     This section provides background information related to the present disclosure and is not necessarily prior art. 
     A climate-control system such as, for example, a heat-pump system, a refrigeration system, or an air conditioning system, may include a fluid circuit having an outdoor heat exchanger, one or more indoor heat exchangers, one or more expansion devices, and one or more compressors circulating a working fluid (e.g., refrigerant or carbon dioxide) through the fluid circuit. Efficient and reliable operation of the climate-control system is desirable to ensure that the climate-control system is capable of effectively and efficiently providing a cooling and/or heating effect on demand. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     In one form, the present disclosure discloses a compressor includes a shell, first and second scroll members, a fluid-injection fitting assembly and a valve assembly. The shell defines a suction chamber. The first scroll member is disposed within the shell and includes a first end plate having a first spiral wrap extending therefrom. The second scroll member is disposed within the shell and includes a second end plate having a second spiral wrap extending therefrom and an injection passage formed in the second end plate. The second spiral wrap is meshingly engaged with the first spiral wrap to form compression pockets. The injection passage being in fluid communication with a radially intermediate one of the compression pockets. The fluid-injection fitting assembly is at least partially disposed within the shell and in fluid communication with the injection passage. The fluid-injection fitting assembly is configured to provide working fluid to the radially intermediate one of the compression pockets. The valve assembly is coupled to one of the second scroll member and the fluid-injection fitting assembly and movable between a closed position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is prevented and an open position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is allowed. The valve assembly is movable from the closed position to the open position when a fluid pressure in the radially intermediate one of the compression pockets exceeds a predetermined threshold value. 
     In some configurations of the compressor of the above paragraph, the fluid-injection fitting assembly includes a scroll fitting and a transfer conduit attached to the scroll fitting. The valve assembly is coupled to the scroll fitting. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly includes a valve housing, a valve body, and a spring that biases the valve body toward the closed position. The valve body is movable relative to the valve housing from the closed position to the open position when fluid pressure in the radially intermediate one of the compression pockets exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows to a passage formed in the scroll fitting and out an aperture formed in the valve housing into the suction chamber when the valve body is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the predetermined threshold value is greater than or equal to 500 psi. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly is coupled to the second end plate of the second scroll member. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly includes a valve housing, a valve body, and a spring that biases the valve body toward the closed position. The valve body is movable relative to the valve housing from the closed position to the open position when a fluid pressure in the radially intermediate one of the compression pockets exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows to the injection passage and out an aperture formed in an end cap of the valve assembly into the suction chamber when the valve body is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the predetermined threshold value is greater than or equal to 500 psi. 
     In some configurations of the compressor of any one or more of the above paragraphs, a passage is formed in the second end plate of the second scroll member and is in fluid communication with the radially intermediate one of the compression pockets. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly includes a valve housing, a valve body, and a spring that biases the valve body toward the closed position. The valve body is movable relative to the valve housing from the closed position to the open position when a fluid pressure in the radially intermediate one of the compression pockets exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows to the passage and out an aperture formed in an end cap of the valve assembly into the suction chamber when the valve body is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the injection passage and the fluid-injection fitting assembly cooperate to define a fluid circuit. Fluid communication between the radially intermediate one of the compression pockets and the suction chamber via the fluid circuit is allowed when the valve assembly is in the open position. 
     In another form, the present disclosure discloses a compressor including a shell, first and second scroll members, a fluid-injection fitting assembly and a valve assembly. The shell defines a suction chamber. The first scroll member is disposed within the shell and includes a first end plate having a first spiral wrap extending therefrom. The second scroll member is disposed within the shell and includes a second end plate having a second spiral wrap extending therefrom and an injection passage formed in the second end plate. The second spiral wrap is meshingly engaged with the first spiral wrap to form compression pockets. The injection passage is in fluid communication with a radially intermediate one of the compression pockets. The fluid-injection fitting assembly is at least partially disposed within the shell and in fluid communication with the injection passage. The fluid-injection fitting assembly is configured to provide working fluid to the radially intermediate one of the compression pockets. The valve assembly is coupled to the fluid-injection fitting assembly and movable between a closed position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is prevented and an open position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is allowed. The valve assembly is movable from the closed position to the open position when a pressure difference of working fluid in the radially intermediate one of the compression pockets and working fluid in the suction chamber exceeds a predetermined threshold value. 
     In some configurations of the compressor of the above paragraph, the fluid-injection fitting assembly includes a scroll fitting and a transfer conduit attached to the scroll fitting. The valve assembly is coupled to the scroll fitting. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly includes a valve flap that is movable relative to the scroll fitting from the closed position to the open position when the pressure difference of working fluid in the radially intermediate one of the compression pockets and working fluid in the suction chamber exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows to a first passage formed in the scroll fitting and out a second passage formed in the scroll fitting into the suction chamber when the valve flap is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the second passage extends perpendicular to the first passage. 
     In some configurations of the compressor of any one or more of the above paragraphs, the fluid-injection fitting assembly includes a scroll fitting and a transfer conduit attached to the scroll fitting. The valve assembly is coupled to the transfer conduit. 
     In some configurations of the compressor of any one or more of the above paragraphs, the valve assembly includes a valve flap that is movable relative to the transfer conduit from the closed position to the open position when the pressure difference of working fluid in the radially intermediate one of the compression pockets and working fluid in the suction chamber exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows through a first passage formed in the scroll fitting and out an aperture formed in the transfer conduit into the suction chamber when the valve flap is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the injection passage and the fluid-injection fitting assembly cooperate to define a fluid circuit. Fluid communication between the radially intermediate one of the compression pockets and the suction chamber via the fluid circuit is allowed when the valve assembly is in the open position. 
     In yet another form, the present disclosure discloses a compressor including a shell, first and second scroll members, a fluid-injection fitting assembly and a valve assembly. The shell defines a suction chamber. The first scroll member is disposed within the shell and includes a first end plate having a first spiral wrap extending therefrom and a venting passage formed in the first end plate. The second scroll member is disposed within the shell and includes a second end plate having a second spiral wrap extending therefrom and an injection passage formed in the second end plate. The second spiral wrap is meshingly engaged with the first spiral wrap to form compression pockets. The injection passage and the venting passage is in fluid communication with a radially intermediate one of the compression pockets. The fluid-injection fitting assembly is at least partially disposed within the shell and in fluid communication with the injection passage. The fluid-injection fitting assembly is configured to provide working fluid to the radially intermediate one of the compression pockets. The valve assembly is coupled to the first end plate and movable between a closed position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is prevented and an open position in which fluid communication between the radially intermediate one of the compression pockets and the suction chamber is allowed. The valve assembly is movable from the closed position to the open position when a fluid pressure within the radially intermediate one of the compression pockets exceeds a predetermined threshold value. 
     In some configurations of the compressor of the above paragraph, the valve assembly includes a valve housing, a valve body, and a spring that biases the valve body toward the closed position. The valve body is movable relative to the valve housing from the closed position to the open position when the fluid pressure in the radially intermediate one of the compression pockets exceeds the predetermined threshold value. 
     In some configurations of the compressor of any one or more of the above paragraphs, working fluid in the radially intermediate one of the compression pockets flows to the venting passage and out an aperture formed in an end cap of the valve assembly into the suction chamber when the valve body is movable from the closed position to the open position. 
     In some configurations of the compressor of any one or more of the above paragraphs, the predetermined threshold value is greater than or equal to 500 psi. 
     In yet another form, the present disclosure discloses a climate-control system including a compressor, a first fluid passageway, a second fluid passageway, a conduit and a valve. The compressor defines a suction chamber and includes a first inlet, a second inlet and a compression mechanism forming a compression pocket. The first inlet is in fluid communication with the suction chamber. The second inlet is in fluid communication with the compression pocket. The first fluid passageway includes a first heat exchanger. The first fluid passageway provides working fluid from the first heat exchanger to the first inlet. The second fluid passageway extends between a second heat exchanger and the second inlet. The second fluid passageway provides working fluid from the second heat exchanger to the second inlet. The conduit extends from the first fluid passageway to the second fluid passageway. The valve is disposed along the conduit and movable between a closed position in which fluid communication between the compression pocket and the suction chamber via the conduit is prevented and an open position in which fluid communication between the compression pocket and the suction chamber via the conduit is allowed. The valve is movable from the closed position to the open position when a fluid pressure in the compression pocket exceeds a predetermined threshold value. 
     In some configurations of the climate-control system of the above paragraph, the predetermined threshold value is greater than or equal to 500 psi. 
     In some configurations of the climate-control system of any one or more of the above paragraphs, the conduit extends from the first fluid passageway at a location between the first inlet and the first heat exchanger to the second fluid passageway at a location between the second heat exchanger and the second inlet. 
     In some configurations of the climate-control system of any one or more of the above paragraphs, the first heat exchanger is an evaporator and the second heat exchanger is a condenser. 
     In some configurations of the climate-control system of any one or more of the above paragraphs, working fluid in the compression pocket flows through the conduit, the first inlet and into the suction chamber when the valve is moved from the closed position to the open position. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG.  1    is a schematic representation of a climate-control system according to the principles of the present disclosure; 
         FIG.  2    is a cross-sectional view of a compressor of the climate-control system of  FIG.  1   ; 
         FIG.  3    is a perspective view of a non-orbiting scroll of the compression mechanism and a fluid-injection fitting assembly; 
         FIG.  4    is a partial cross-sectional view of the fluid-injection fitting assembly of  FIG.  3    having a valve assembly in an open position; 
         FIG.  5    is a cross-sectional view of the valve assembly in the closed position; 
         FIG.  6    is a cross-sectional view of the valve assembly in the open position; 
         FIG.  7    is a partial cross-sectional view of an alternate fluid-injection fitting assembly having a valve assembly in a closed position; 
         FIG.  8    is a partial cross-sectional view of the fluid-injection fitting assembly of  FIG.  7    with the valve assembly in an open position; 
         FIG.  9    is a partial cross-sectional view of yet another alternate fluid-injection fitting assembly; 
         FIG.  10    is a perspective view of a transfer conduit of the fluid-injection fitting assembly of  FIG.  9    having a valve assembly in a closed position; 
         FIG.  11    is a perspective view of the transfer conduit of the fluid-injection fitting assembly of  FIG.  9    having the valve assembly in an open position; 
         FIG.  12    is a partial perspective view of an alternate non-orbiting scroll and an alternate fluid-injection fitting assembly; 
         FIG.  13    is a partial cross-sectional view of the non-orbiting scroll and fluid-injection fitting assembly of  FIG.  12   ; 
         FIG.  14    is a schematic representation of an alternate climate-control system according to the principles of the present disclosure; 
         FIG.  15    is a perspective view of another alternate non-orbiting scroll and an alternate fluid-injection fitting assembly; 
         FIG.  16    is a cross-sectional view of the non-orbiting scroll and fluid-injection fitting assembly of  FIG.  15   ; and 
         FIG.  17    is a cross-sectional view of an alternate orbiting scroll according to the principles of the present disclosure. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
     The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
     When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
     Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     With reference to  FIG.  1   , a climate-control system  10  is provided that may include a fluid-circuit having a compressor  12 , a first heat exchanger  14  (an outdoor heat exchanger such as a condenser or gas cooler, for example), first and second expansion devices  16 ,  18 , a second heat exchanger  20  and a third heat exchanger  22  (an indoor heat exchanger such as an evaporator). The compressor  12  may pump working fluid (e.g., refrigerant, carbon dioxide, etc.) through the circuit. 
     As shown in  FIG.  2   , the compressor  12  may be a low-side compressor (i.e., a compressor in which the motor assembly is disposed within a suction chamber or suction-pressure region of the compressor), for example. The compressor  12  may include a hermetic shell assembly  24 , a motor assembly  26 , a main bearing housing  28 , a compression mechanism  30 , a seal assembly  32 , a suction gas inlet fitting  34  (e.g., a first inlet of the compressor  12 ) and a fluid-injection fitting assembly  36  (e.g., a second inlet of the compressor  12 ). 
     The shell assembly  24  may generally form a compressor housing and may include a cylindrical shell  38 , an end cap  40  at an upper end thereof, a transversely extending muffler plate  42  and a base  44  at a lower end thereof. The end cap  40  and the muffler plate  42  may generally define a discharge chamber  46 , while the cylindrical shell  38 , the muffler plate  42  and the base  44  may generally define a suction chamber  48 . A discharge fitting (not shown) may be attached to the shell assembly  24  at an opening (not shown) in the end cap  40  and may be in fluid communication with the first heat exchanger  14 . The suction gas inlet fitting  34  may be attached to the shell assembly  24  at an opening  50  such that the suction gas inlet fitting  34  is in fluid communication with the third heat exchanger  22 . The muffler plate  42  may include a discharge passage  52  extending therethrough that provides communication between the compression mechanism  30  and the discharge chamber  46 . 
     The motor assembly  26  may generally include a motor stator  54 , a rotor  56  and a driveshaft  58 . The motor stator  54  may be fixedly coupled with shell  38  (e.g., press-fit into the shell  38 ). The driveshaft  58  may be rotatably driven by the rotor  56 . The rotor  56  may be press-fit onto the driveshaft  58 . 
     The main bearing housing  28  may be affixed to the shell  38  at a plurality of points in any desirable manner, such as staking, for example, and may axially support the compression mechanism  30 . The main bearing housing  28  may include a bearing that rotatably supports one end of the driveshaft  58 . The other end of the driveshaft  58  may be supported by a lower bearing housing  60 . 
     As shown in  FIG.  2   , the compression mechanism  30  may generally include an orbiting scroll or first scroll member  62  and a non-orbiting scroll or second scroll member  64 . The orbiting scroll  62  may include an endplate  66  having a spiral vane or wrap  68  on the upper surface thereof and an annular flat thrust surface  70  on the lower surface. The thrust surface  70  may interface with the annular flat thrust bearing surface  72  on the main bearing housing  28 . A cylindrical hub  74  may project downwardly from the thrust surface  70  and may have a drive bushing  76  rotatably disposed therein. The drive bushing  76  may include an inner bore in which the driveshaft  58  is drivingly disposed. An Oldham coupling may be engaged with the orbiting and non-orbiting scrolls  62 ,  64  to prevent relative rotation therebetween. 
     The non-orbiting scroll  64  may include an endplate  84  having a spiral wrap  86  on a lower surface thereof. The spiral wrap  86  may form a meshing engagement with the wrap  68  of the orbiting scroll  62 , thereby creating compression pockets, including an inlet pocket  90  (i.e., a radially outer pocket), intermediate pockets  92 ,  94 ,  96  (i.e., radially intermediate pockets), and an outlet pocket  98  (i.e., a radially inner pocket). The non-orbiting scroll  64  may include a discharge passage  100  in communication with the outlet pocket  98  and an upwardly open recess  102 . The upwardly open recess  102  may be in fluid communication with the discharge chamber  46  via the discharge passage  52  in the muffler plate  42 . 
     The endplate  84  may include a fluid-injection passage  104  formed therein. The fluid-injection passage  104  may be in fluid communication with the fluid-injection fitting assembly  36  and with one or more of the intermediate pockets  92 ,  94 ,  96 , and may include a radially extending portion  106  and an axially extending portion  108 . The fluid-injection passage  104  may allow working fluid from the fluid-injection fitting assembly  36  to flow into the one or more of the intermediate pockets  92 ,  94 ,  96 . The non-orbiting scroll  64  may include an annular recess  110  in the upper surface thereof. 
     As shown in  FIG.  2   , the seal assembly  32  may be located within the annular recess  110 . In this way, the seal assembly  32  may be axially displaceable within the annular recess  110  relative to the shell assembly  24  and/or the non-orbiting scroll  64  to provide for axial displacement of the non-orbiting scroll  64  while maintaining a sealed engagement with the muffler plate  42  to isolate the discharge chamber  46  from the suction chamber  48 . More specifically, in some configurations, pressure within the annular recess  110  may urge the seal assembly  32  into engagement with the muffler plate  42 , and the spiral wrap  86  of the non-orbiting scroll  64  into engagement with the endplate  66  of the orbiting scroll  62 , during normal compressor operation. 
     With reference to  FIGS.  2 - 6   , the fluid-injection fitting assembly  36  may include a scroll fitting  114 , a transfer conduit  116 , a valve assembly  118  ( FIGS.  2  and  4 - 6   ), and a shell fitting  126 . The scroll fitting  114  may be at least partially disposed in the shell  38  and may be attached to the non-orbiting scroll  64  via bolts  120 . The scroll fitting  114  may include a passage  122  that is in fluid communication with the injection passage  104  at a first end and in fluid communication with the transfer conduit  116  and the valve assembly  118  at a second end. A sealing member  124  (e.g., a gasket) is disposed between the non-orbiting scroll  64  and the scroll fitting  114  to prevent leakage from or into the injection passage  104  and/or the scroll fitting  114 . 
     As shown in  FIG.  2   , the shell fitting  126  (i.e., a second inlet) is attached to the shell  38  at an opening thereof. The transfer conduit  116  may be at least partially disposed in the shell  38  and may be attached to the scroll fitting  114  at a first end and to the shell fitting  126  at a second end. The transfer conduit  116  may be in fluid communication with the passage  122  of the scroll fitting  114  at the first end and may be in fluid communication with a passage  128  of the shell fitting  126  at the second end. With reference to  FIGS.  4 - 6   , a first sealing member  130  (e.g., an O-ring) may be disposed in a groove  132  formed in the transfer conduit  116  at or near the first end and a second sealing member  134  (e.g., an O-ring) may be disposed in a groove  136  formed in the transfer conduit  116  at or near the second end. In this way, the first and second sealing members  130 ,  134  prevent leakage from or into the transfer conduit  116 , the scroll fitting  114  and/or the shell fitting  126 . In some configurations, the transfer conduit  116  could be integrally formed with or a part of the scroll fitting  114  or the shell fitting  126 . 
     As shown in  FIGS.  2  and  4 - 6   , the valve assembly  118  may include a valve housing  138 , an end cap  140  a valve body  142  and a coiled spring  144 . The valve housing  138  may be fixedly coupled to the scroll fitting  114  and may include an end wall  145  and a sidewall  146  that cooperate to define a valve-housing passage  147 . The end wall  145  may define a first opening  148  and the sidewall  146  may define second openings  149 . The first opening  148  is in fluid communication with the passage  122  of the scroll fitting  114  and also selectively in fluid communication with the second openings  149  via the valve-housing passage  147 . The second openings  149  may be in fluid communication with the suction chamber  48  and selectively in fluid communication with the valve-housing passage  147 . The end cap  140  is attached to the valve housing  138  at an end opposite the end wall  145 . 
     The valve body  142  and the coiled spring  144  are disposed in the valve-housing passage  147  of the valve housing  138 . The valve body  142  may be disposed within the valve-housing passage  147  and movable relative to the valve housing  138  between a closed position and an open position. In the closed position ( FIG.  5   ), the valve body  142  may sealingly engage the end wall  145  to prevent fluid communication between the first opening  148  and the valve-housing passage  147 . In the open position ( FIG.  6   ), the valve body  142  may be spaced apart from the end wall  145 , thereby allowing fluid communication between the first opening  148  and the valve-housing passage  147 . The coiled spring  144  is connected to the end cap  140  and the valve body  142 , and biases the valve body  142  into the closed position. 
     While the compressor  12  is described above as a low-side scroll compressor (i.e., a compressor in which the motor assembly is disposed within a suction-pressure chamber within the shell), in some configurations, the compressor  12  could be a high-side compressor (i.e., a compressor in which the motor assembly is disposed within a discharge-pressure chamber within the shell). For example, the compressor  12  could be a high-side or low-side compressor and could be a rotary, reciprocating, or screw compressor, or any other suitable type of compressor. 
     With reference back to  FIG.  1   , the first heat exchanger  14  may be in fluid communication with the compressor  12  and may receive compressed working fluid from the compressor  12  via a discharge line  150  that is connected to the discharge fitting (not shown) of the compressor  12 . The first heat exchanger  14  may transfer heat from the compressed working fluid to ambient air that may be forced over the first heat exchanger  14 . In some configurations, the first heat exchanger  14  may transfer heat from the compressed working fluid to a stream of liquid such as water, for example. 
     From the first heat exchanger  14 , a first portion of the working fluid may flow to a first fluid passageway  152 . The first fluid passageway  152  may include the first expansion device  16  (e.g., an expansion valve or capillary tube), a first conduit  154  of the second heat exchanger  20 , and the third heat exchanger  22 . The working fluid in the first fluid passageway  152  flows through the conduit  154  of the second heat exchanger  20  and the first expansion device  16  where its temperature and pressure are lowered. The working fluid then flows to the third heat exchanger  22  where the working fluid may absorb heat from a space to be cooled. From the third heat exchanger  22 , the working fluid flows to the suction gas inlet fitting  34  (via a suction line  156 ) to be compressed by the compression mechanism  30 . 
     A second portion of the working fluid from the first heat exchanger  14  may flow to a second fluid passageway  158  (e.g., a fluid-injection passageway). The second fluid passageway  158  may include the second expansion device  18  (e.g., an expansion valve or capillary tube) and a conduit  160  of the second heat exchanger  20 . The working fluid in the second fluid passageway  158  may flow through the second expansion device  18  where its pressure is lowered. The working fluid then flows through the conduit  160  of the second heat exchanger  20  where it absorbs heat from the working fluid flowing through the conduit  154 . The working fluid then flows to the fluid-injection fitting assembly  36  and into the intermediate pocket  92  of the compression mechanism  30  (via the injection passage  104 ). In this manner, the second fluid passageway  158 , the fluid-injection fitting assembly  36 , and the injection passage  104  may define a fluid-injection circuit. In some configurations, the second heat exchanger  20  may be a counter-flow heat exchanger as oppose to a parallel-flow heat exchanger. In some configurations, the system  10  may not include the second heat exchanger  20 , e.g., if liquid injection (as opposed to vapor injection) is desired. 
     When the compressor  12  is in an OFF-mode, the compressor  12  may experience a flooded start condition. A flooded start condition is a condition where working fluid in a liquid phase (i.e., a mixture of gaseous and liquid working fluid or entirely liquid working fluid) may migrate into or otherwise be present in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  of the compression mechanism  30  when the compressor  12  is switched from the OFF-mode to an ON-mode. During a flooded start condition, high fluid pressure (e.g., fluid pressures greater than or equal to 500 pounds per square inch (psi)) may be generated in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  when the compression mechanism  30  compresses working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  that is at least partially in liquid phase. 
     During normal operation of the system  10 , intermediate-pressure working fluid may flow through the fluid-injection circuit from the second fluid passageway  158 , through the fluid-injection fitting assembly  36 , through the injection passage  104  and into the intermediate compression pocket  92 ). If the high pressure working fluid in the compression pocket  92  and/or the fluid-injection circuit exceeds a predetermined threshold value (e.g., during a flooded start condition), the coiled spring  144  of the valve assembly  118  will compress, thereby moving the valve body  142  from the closed position ( FIG.  5   ) to the open position ( FIG.  6   ). Once the valve body  142  is moved from the closed position to the open position, high pressure working fluid in the compression pocket  92  and/or the fluid-injection circuit (e.g., the passage  122 ) flows through the first opening  148 , the valve-housing passage  147 , and out the second openings  149  into the suction chamber  48 . 
     It should be understood that the coiled spring  144  may compress in response to high pressure working fluid in the compression pocket  92  being above a predetermined threshold value due to the compressor  12  experiencing a flooded start condition and not during normal operation of the system  10 . Stated another way, fluid pressures in the compression pocket  92  and in the fluid-injection circuit during normal operation of the system  10  are below the predetermined threshold value that causes the spring  144  to compress and the valve body  142  to move from the closed position to the open position. 
     One of the benefits of the climate-control system  10  of the present disclosure is the reduction of pressure of the high pressure working fluid generated during a flooded start condition, which increases the reliability of the compressor  12 . That is, a flooded start condition may be detrimental to the reliability of the compressor  12  and, in turn, the efficient operation of the climate-control system  10 . By reducing the pressure of the high pressure working fluid generated during a flooded start condition, the compressor  12  is more reliable, which allows for efficient operation of the climate-control system  10 . 
     Another benefit of the climate-control system  10  of the present disclosure is the prevention of damage to the gasket  124  and the reduction of moment on the fitting  114  due to venting excessively high pressure working fluid to the suction chamber  48 . This allows the gasket  124  to maintain a proper seal between the scroll  64  and the fitting  114 . 
     With reference to  FIGS.  7 - 8   , another fluid-injection fitting assembly  236  is provided. The fluid-injection fitting assembly  236  may be incorporated into the compressor  12  instead of the fluid-injection fitting assembly  36 . The structure and function of the fluid-injection fitting assembly  236  may be similar or identical to that of the fluid-injection fitting assembly  36  described above, apart from any exception noted below. 
     The fluid-injection fitting assembly  236  may include a scroll fitting  238 , a valve flap  240  and a transfer conduit (not shown). The scroll fitting  238  may be at least partially disposed in the shell  38  and may be attached to the non-orbiting scroll  64  via bolts (not shown). The scroll fitting  238  may include a first passage  242  and a second passage  243 . The first passage  242  may be in fluid communication with the injection passage  104  at a first end and in fluid communication the transfer conduit at a second end. The second passage  243  may be in fluid communication with the first passage  242  and in selective fluid communication with the suction chamber  48 . 
     The valve flap  240  may be movably mounted to the scroll fitting  238  (via fasteners  246 ; only one shown in  FIGS.  7  and  8   ) between a closed position ( FIG.  7   ) and an open position ( FIG.  8   ). In the closed position, the valve flap  240  may be sealingly engaged with the scroll fitting  238  to prevent fluid communication between the first passage  242  and the suction chamber  48 . In the open position, the valve flap  240  may be spaced apart from the scroll fitting  238 , thereby allowing fluid communication between the first passage  242  and the suction chamber  48  (via the second passage  243 ). 
     High pressure working fluid in the compression pocket  92  may flow at least partially through a fluid-injection circuit (the fluid-injection circuit may be defined by the injection passage  104 , the passages  242 ,  243  of the scroll fitting  238 , the transfer conduit (not shown), the shell fitting  126  and the second fluid passageway  158 ). If a pressure difference between high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and working fluid in the suction chamber  48  exceeds a predetermined threshold, the valve flap  240  moves from the closed position to the open position. Once the valve flap  240  is moved from the closed position to the open position, high pressure working fluid in the compression pocket  92  and/or the fluid-injection circuit (e.g., the passages  242 ,  243 ) is vented out into the suction chamber  48 . The valve flap  240  moves from the open position back to the closed position once the pressure difference between the high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and the working fluid in the suction chamber  48  is below the predetermined threshold. 
     The structure and function of the transfer conduit (not shown) may be similar or identical to that of the transfer conduit  116  described above, and therefore, will not be described again in detail. 
     It should be understood that the valve flap  240  may move from the closed position to the open position in response to a pressure difference between high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and working fluid in the suction chamber  48  exceeding a predetermined threshold value due to the compressor  12  experiencing a flooded start condition and not during normal operation of the system  10 . Stated another way, the pressure difference between high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and working fluid in the suction chamber  48  during normal operation of the compressor  12  is below the predetermined threshold value and would not cause the valve flap  240  to move from the closed position to the open position. 
     With reference to  FIGS.  9 - 11   , another fluid-injection fitting assembly  336  is provided. The fluid-injection fitting assembly  336  may be incorporated into the compressor  12  instead of the fluid-injection fitting assemblies  36 ,  236 . The structure and function of the fluid-injection fitting assembly  336  may be similar or identical to that of the fluid-injection fitting assemblies  36 ,  236  described above, apart from any exception noted below. 
     The fluid-injection fitting assembly  336  may include a scroll fitting  338  and a transfer conduit  340 . The scroll fitting  338  may be at least partially disposed in the shell  38  and may be attached to the non-orbiting scroll  64  via bolts  339 . The scroll fitting  338  may include a fluid passage  342  that may be in fluid communication with the injection passage  104  at a first end and in fluid communication with the transfer conduit  340  at a second end. 
     The transfer conduit  340  may be at least partially disposed in the shell  38  and may be attached to the scroll fitting  338  at a first end and to the shell fitting  126  at a second end. A passage  345  of the transfer conduit  340  may be in fluid communication with the fluid passage  342  of the scroll fitting  338  at the first end and may be in fluid communication with the passage  128  of the shell fitting  126  at the second end. A first sealing member  346  (e.g., an O-ring) may be disposed in a groove  348  formed in the transfer conduit  340  at or near the first end and a second sealing member  350  (e.g., an O-ring) may be disposed in a groove  352  formed in the transfer conduit  340  at or near the second end. In this way, the first and second sealing members  346 ,  350  prevent leakage from or into the transfer conduit  340 , the scroll fitting  338  and/or the shell fitting  126 . 
     The fluid-injection fitting assembly  336  also includes a valve flap  354  that may be movably mounted to the transfer conduit  340  (via a fastener  355 ) between a closed position ( FIG.  10   ) and an open position ( FIG.  11   ). In the closed position, the valve flap  354  may be sealingly engaged with the transfer conduit  340  to prevent fluid communication between the passage  345  and the suction chamber  48 . In the open position, the valve flap  354  may be spaced apart from the transfer conduit  340 , thereby allowing fluid communication between the passage  345  and the suction chamber  48  via an aperture  347  in the transfer conduit  340 . 
     As shown in  FIG.  9   , high pressure working fluid in the compression pocket  92  may flow at least partially through a fluid-injection circuit (the fluid-injection circuit may be defined by the injection passage  104 , the passage  342  of the scroll fitting  338 , the passage  345  of the transfer conduit  340 , the passage  128  of the shell fitting  126  and the second fluid passageway  158 ). If a pressure difference between high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and working fluid in the suction chamber  48  exceeds a predetermined threshold, the valve flap  354  moves from the closed position to the open position. Once the valve flap  354  is moved from the closed position to the open position, high pressure working fluid in the compression pocket  92  and/or the fluid-injection circuit (e.g., the passage  345 ) is vented out into the suction chamber  48 . The valve flap  354  moves from the open position back to the closed position once the pressure difference between high pressure working fluid in the compression pockets  90 ,  92 ,  94 ,  96 ,  98  (and/or the fluid-injection circuit) and working fluid in the suction chamber  48  is below the predetermined threshold. 
     With reference to  FIGS.  12 - 13   , another compression mechanism  430  and fluid-injection fitting assembly  436  are provided. The compression mechanism  430  may be incorporated into the compressor  12  instead of the compression mechanism  30  described above. The structure and function of the compression mechanism  430  may be similar or identical to that of the compression mechanism  30  described above, apart from any exception noted below. 
     The compression mechanism  430  may generally include an orbiting scroll or first scroll member (not shown), a non-orbiting scroll or second scroll member  440  and a valve assembly  442 . The structure and function of the orbiting scroll may be similar or identical to that of the orbiting scroll  62  described above, and therefore, will not be described again in detail. 
     The non-orbiting scroll  440  may include an endplate  444  having a spiral wrap (not shown) projecting downwardly from the endplate  444 . The spiral wrap may form a meshing engagement with the wrap (not shown) of the orbiting scroll, thereby creating compression pockets (not shown). The endplate  444  may include an injection passage  446  formed therein. The injection passage  446  may be in fluid communication with the fluid-injection fitting assembly  436  and one or more of the intermediate pockets of the compression pockets. The injection passage  446  may also be in selective fluid communication with the suction chamber  48  via the valve assembly  442 . The injection passage  446  may allow working fluid from fluid-injection fitting assembly  436  to flow into the one or more of the intermediate pockets. 
     The valve assembly  442  may include a valve housing  448 , a valve body  450 , a coiled spring  452  and an end cap  454 . The valve housing  448  may be coupled to the end plate  444  of the non-orbiting scroll  440 . The valve body  450  may be disposed within the valve housing  448  and may be translatable between a closed position and an open position. In the closed position, the valve body  450  may prevent fluid communication between the injection passage  446  and the suction chamber  48 . In the open position, the valve body  450  may allow fluid communication between the injection passage  446  and the suction chamber  48  (via openings  455 ,  456  in the valve housing  448  and the end cap  454 , respectively). The coiled spring  452  is connected to the end cap  454  and the valve body  450 , and biases the valve body  450  into the closed position. The end cap  454  is coupled to an end of the valve housing  448 . 
     The fluid-injection fitting assembly  436  may be incorporated into the compressor  12  instead of the fluid-injection fitting assemblies  36 ,  236 ,  336  described above. The structure and function of the fluid-injection fitting assembly  436  may be similar or identical to that of the fluid-injection fitting assemblies  36 ,  236 ,  336  described above, apart from any exception noted below. 
     The fluid-injection fitting assembly  436  may include a scroll fitting  460  and a transfer conduit  462 . The scroll fitting  460  may be at least partially disposed in the shell  38  and may be attached to the non-orbiting scroll  440  via bolts  463 . The scroll fitting  460  may include a passage  464  that is in fluid communication with the injection passage  446  at a first end and in fluid communication with the transfer conduit  462  at a second end. A sealing member  466  (e.g., a gasket) is disposed between the non-orbiting scroll  440  and the scroll fitting  460  to prevent leakage from or into the injection passage  446  and/or the scroll fitting  460 . 
     The structure and function of the transfer conduit  462  may be similar or identical to the transfer conduit  116  described above, and therefore, will not be described again in detail. 
     High pressure working fluid in an intermediate compression pocket may flow at least partially through a fluid-injection circuit (the fluid-injection circuit may be defined by the injection passage  446 , the passage  464  of the scroll fitting  460 , the transfer conduit  462 , the shell fitting  126  and the second fluid passageway  158 ). If fluid pressures in the compression pockets and the fluid-injection circuit exceeds a predetermined threshold value, the coiled spring  452  of the valve assembly  442  will compress, thereby moving the valve body  450  from the closed position to the open position. Once the valve body  450  is moved from the closed position to the open position, high pressure working fluid in the intermediate compression pocket and/or the fluid-injection circuit (e.g., the passage  446 ) flows through the valve housing  448  and into the suction chamber  48 . 
     With reference to  FIG.  14   , another climate-control system  510  is provided. The structure and function of the climate control system  510  may be similar or identical to that of climate-control system  10  described above, apart from any exception noted below. 
     The climate-control system  510  may include a fluid-circuit having a compressor  512 , a first heat exchanger  514  (an outdoor heat exchanger such as a condenser or gas cooler, for example), first and second expansion devices  516 ,  518 , a second heat exchanger  520  and a third heat exchanger  522  (an indoor heat exchanger such as an evaporator). The structure and the function of the compressor  512 , the first heat exchanger  514 , the first and second expansion devices  516 ,  518 , the second heat exchanger  520  and the third heat exchanger  522  may be similar or identical to that of the compressor  12 , the first heat exchanger  14 , the first and second expansion devices  16 ,  18 , the second heat exchanger  20  and the third heat exchanger  22 , respectively, described above, and therefore, will not be described again in detail. 
     The climate-control system  510  may also include a conduit  554  extending between a first fluid passageway  556  and a second fluid passageway  558 . The first fluid passageway  556  may include the first expansion device  516  and the third heat exchanger  522 , and the second fluid passageway  558  may include the second expansion device  518 . 
     A valve  562  (e.g., a pressure-relief valve) may be disposed along the conduit  554  and may vent high pressure working fluid generated in an intermediate compression pocket (not shown) of the compression mechanism (not shown) of the compressor  512  to a suction chamber (not shown) of the compressor  512 . That is, if fluid pressures in the compression pockets due to the compressor  512  experiencing a flooded start condition exceeds a predetermined threshold value, the valve  562  will open and the high pressure working fluid may flow through a second inlet  564  (i.e., a fluid-injection fitting assembly), through the conduit  554  and into the suction chamber (via a suction line  566  and first inlet  568  (i.e., suction inlet gas fitting)). It should be understood that during normal operation of the system  510 , fluid pressures are below the predetermined threshold value, and thus, the valve  562  is in the closed position. 
     With reference to  FIGS.  15 - 16   , another compression mechanism  630  and fluid-injection fitting assembly  636  is provided. The compression mechanism  630  may be incorporated into the compressor  12  instead of the compression mechanisms  30 ,  430  described above. The structure and function of the compression mechanism  630  may be similar or identical to that of the compression mechanisms  30 ,  430  described above, apart from any exception noted below. 
     The compression mechanism  630  may generally include an orbiting scroll or first scroll member (not shown), a non-orbiting scroll or second scroll member  640  and a valve assembly  642 . The structure and function of the orbiting scroll may be similar or identical to that of the orbiting scroll  62  described above, and therefore, will not be described again in detail. 
     The non-orbiting scroll  640  may include an endplate  644  having a spiral wrap  645  projecting downwardly from the endplate  644 . The spiral wrap  645  may form a meshing engagement with the wrap (not shown) of the orbiting scroll, thereby creating compression pockets (not shown). The endplate  644  may include an injection passage  646  and a venting passage  647  formed therein. The injection passage  646  may be in fluid communication with the fluid-injection fitting assembly  636  and one or more of the compression pockets. The injection passage  646  may allow working fluid from the fluid-injection fitting assembly  636  to flow into the one or more of the compression pockets. The venting passage  647  may be in fluid communication with the compression pockets and with the suction chamber  48  (via the valve assembly  642 ). 
     The function and structure of the valve assembly  642  may be similar or identical to that of the valve assembly  442 , described above, and therefore, will not be described again in detail. The valve assembly  642  may be coupled to the endplate  644  and may allow fluid communication between the compression pockets and the suction chamber  48 . 
     The fluid-injection fitting assembly  636  may include a scroll fitting  660  and a transfer conduit  662 . The scroll fitting  660  may be at least partially disposed in the shell  38  and may be attached to the non-orbiting scroll  640  via bolts  663 . The scroll fitting  660  may include a passage  664  that is in fluid communication with the injection passage  646  at a first end and in fluid communication with the transfer conduit  662  at a second end. A sealing member  666  (e.g., a gasket) is disposed between the non-orbiting scroll  640  and the scroll fitting  660  to prevent leakage from or into the injection passage  646  and/or the scroll fitting  660 . 
     The structure and function of the transfer conduit  662  may be similar or identical to the transfer conduit  116 ,  462  described above, and therefore, will not be described again in detail. 
     If fluid pressures in the compression pockets due to the compressor  12  experiencing a flooded start condition exceeds a predetermined threshold value, the high pressure working fluid may flow through the venting passage  647  and into the suction chamber  48  (via the valve assembly  642 ). It should be understood that during normal operation of the system, fluid pressures are below the predetermined threshold value, and thus, the valve assembly  642  is in the closed position. 
     With reference to  FIG.  17   , another compression mechanism  730  is provided. The compression mechanism  730  may be incorporated into the compressor  12  instead of the compression mechanism  30 ,  430 ,  630  described above. The structure and function of the compression mechanism  730  may be similar or identical to that of the compression mechanism  30 ,  430 ,  630  described above, apart from any exception noted below. 
     The compression mechanism  730  may generally include a non-orbiting scroll (not shown), an orbiting scroll  762  and a valve assembly  742 . The structure and function of the non-orbiting scroll may be similar or identical to that of the non-orbiting scroll  64  described above, and therefore, will not be described again in detail. 
     The orbiting scroll  762  may include an endplate  766  having a spiral vane or wrap  768  on the upper surface thereof and an annular flat thrust surface  770  on the lower surface. The wrap  768  may form a meshing engagement with the wrap (not shown) of the non-orbiting scroll, thereby creating compression pockets. The endplate  766  may include a venting passage  779  that may be in fluid communication with the compression pockets and with the suction chamber  48  (via the valve assembly  742 ). The venting passage  779  may have an axial extending portion  780  and a radial extending portion  782 . The thrust surface  770  may interface with the annular flat thrust bearing surface  72  on the main bearing housing  28 . A cylindrical hub  774  may project downwardly from the thrust surface  770  and may have a drive bushing (not shown) rotatably disposed therein. 
     The function and structure of the valve assembly  742  may be similar or identical to that of the valve assembly  442 ,  642  described above, and therefore, will not be described again in detail. The valve assembly  742  may be coupled to the endplate  766  and may allow fluid communication between the compression pockets and the suction chamber  48 . 
     If fluid pressures in the compression pockets due to the compressor  12  experiencing a flooded start condition exceed a predetermined threshold value, the high pressure working fluid may flow through the venting passage  779  and into the suction chamber  48  (via the valve assembly  742 ). It should be understood that during normal operation of the system, fluid pressures are below the predetermined threshold value, and thus, the valve assembly  742  is in the closed position. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.