Patent Publication Number: US-2023149838-A1

Title: Filter cartridge, and method of retrofitting filter housing

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 USC 119 of U.S. Provisional Patent Application No. 63/279,298, filed Nov. 15, 2021, the disclosure of which is hereby incorporated herein by reference in its entirety. 
    
    
     FIELD 
     This disclosure generally relates to a filter assembly. More particularly, this disclosure relates to a removable filter cartridge in a filter assembly. 
     BACKGROUND 
     Filters can be employed in semiconductor manufacturing to remove contaminants from a fluid. A filter head can direct a fluid (e.g., liquid, water, or the like) through a removable filter. The filter can be configured to remove containment such as, for example, solids as the liquid passes through the filter. In particular, a filter can be used to remove solid containments from a liquid as the liquid passes through the filter. A filter becomes saturated with trapped containments (e.g., solids) over time and is then replaced. Conventionally, the housing of the filter is drained and then removed and replaced with a new filter. 
     SUMMARY 
     In an embodiment, a removable filter cartridge includes a filter housing and a sealing valve assembly. The filter housing has an internal volume containing a filter configured to filter liquid passing through the internal volume, the filter housing including an open end with an inlet and an outlet. The sealing valve assembly including a first end configured to be removably coupled to a filter head, a second end coupled to the open end of the filter housing, an inlet passageway configured to direct liquid into the inlet of the filter housing, and an outlet passageway configured to direct the liquid discharged from the outlet of the filter housing after being filtered by the filter. The sealing valve assembly also includes an inlet sealing valve configured to block the inlet passageway and an outlet sealing valve configured to block the outlet passageway when the sealing valve assembly is uncoupled from the filter head such that the internal volume is sealed while the removable filter cartridge is uncoupled from the filter head. 
     In an embodiment, a sealing valve assembly for a removable filter cartridge includes a first end, a second end, and an inlet passageway and an outlet passageway that each extend through the sealing valve assembly. The first end is configured to removably couple to a filter head. The second end is configured to couple the sealing valve assembly to a filter housing to form the removable filter cartridge such that the inlet passageway directs liquid into an inlet of the filter housing and the outlet passageway directs the liquid discharged from an outlet of the filter housing after passing through the filter housing. The sealing valve assembly also including an inlet sealing valve configured to block the inlet passageway and an outlet sealing valve configured to block the outlet passageway when the sealing valve assembly is uncoupled from the filter head such that the internal volume is sealed while the removable filter cartridge is uncoupled from the filter head. 
     In an embodiment, a method of retrofitting a filter housing includes removing the filter housing from a filter head, coupling a sealing valve assembly to the filer housing to form a removable filter cartridge, and coupling the filter cartridge to the filter head. Removing the filter housing from the filter head includes uncoupling the filter housing from the filter head. Coupling the sealing valve assembly to the filter housing includes coupling a first end of the sealing valve assembly to an open end of the filter housing. Coupling the removable filter cartridge to the filter head includes coupling a second end of the sealing valve assembly to the filter head. 
    
    
     
       DRAWINGS 
         FIG.  1    is front perspective view of an embodiment of a filter assembly. 
         FIG.  2    is an exploded view of the removable filter cartridge in  FIG.  1   , according to an embodiment. 
         FIG.  3    is a top view of the filter assembly in  FIG.  1   , according to an embodiment. 
         FIG.  4    is a vertical cross-sectional view of filter assembly along the line IV-IV in  FIG.  3    with a valve sealing assembly of the filter assembly in the open position, according to an embodiment. 
         FIG.  5    is a vertical cross-sectional view of the filter assembly along the line IV-IV in  FIG.  3    with the valve sealing assembly in the closed position, according to an embodiment. 
         FIG.  6    is front perspective view of another embodiment of a filter assembly. 
         FIG.  7    is an exploded view of the removable filter cartridge in  FIG.  6   , according to an embodiment. 
         FIG.  8    is a vertical cross-sectional view of the filter assembly in  FIG.  6    with a valve sealing assembly of the filter assembly in the open position, according to an embodiment. 
         FIG.  9    is a vertical cross-sectional view of a removable filter cartridge of the filter assembly in  FIG.  7    when uncoupled from a filter head, according to an embodiment. 
         FIG.  10    is a block flow diagram of an embodiment of a method of retrofitting a filter housing. 
     
    
    
     Like numbers represent like features. 
     DETAILED DESCRIPTION 
       FIGS.  1  and  2    show an embodiment of a filter assembly  1 .  FIG.  1    is a front perspective view of the filter assembly  1 . The filter assembly  1  includes a fluid inlet  2  and a fluid outlet  4 . A fluid to be filtered is supplied to the fluid inlet  2 , is filtered by the filter assembly  1 , and then the filtered fluid is directed out from the fluid outlet  4  of the filter assembly  1 . The filter assembly  1  removes solids from the fluid as the fluid passes through. In an embodiment, the fluid is liquid or mostly liquid. For example, the liquid may be water (e.g., deionized water), HCl, HNO 3 , isopropyl alcohol, or the like. In an embodiment, the fluid is water. The filter assembly  1  includes a removable filter cartridge  10  that is coupled to a filter head  90 . The removed solids remain within the filter cartridge  10 . The filter head  90  includes the fluid inlet  2  and the fluid outlet  4  of the filter assembly  1 . 
     The removable filter cartridge  10  is configured to be removed from the filter head  90 . For example, the removable filter cartridge  10  is removed when due for replacement. The removable filter cartridge  10  may be due for replacement after performing a predetermined amount of filtering. For example, after the removable filter cartridge  10  has filtered predetermined amount of fluid, has filtered a predetermined amount of material from the fluid, has been in use for a predetermined amount of time, has reached a particular saturation of filtered material, etc. 
     The removable filter cartridge  10  includes a filter housing  20  and a sealing valve assembly  40 . The sealing valve assembly  40  is coupled to the filter housing  20  to form the removable filter cartridge  10 . The sealing valve assembly  40  removably couples the removable filter cartridge  10  to the filter head  90 . As shown in  FIG.  1   , the filter housing  20  is removably coupled to the filter head  90  by the sealing valve assembly  40 . 
       FIG.  2    is an exploded view of the removable filter cartridge  10 .  FIG.  2    shows the filter housing  20 , sealing valve assembly  40 , and filter head  90  when uncoupled from each other. In the illustrated embodiment, the sealing valve assembly  40  is uncoupled from the filter head  90  by being unscrewed from the filter head  90 , and the filter housing  20  is uncoupled from the sealing valve assembly  40  by being unscrewed from the filter head  90 . The sealing valve assembly  40  includes sealing valves for sealing the filter housing  20 . The sealing valves include an inlet sealing valve  70 A configured to block flow of liquid into the filter housing  20  (e.g., from the filter head  90 ) and an outlet sealing valve  70 B configured to block flow of liquid out of the filter housing  20  (e.g., to the filter head  90 ). The inlet sealing valve  70 A and the outlet sealing valve  70 B when closed are configured to seal the filter housing  20 . 
       FIG.  3    is a top view of the filter assembly  1 . The sealing valve assembly  40  has an open position and a closed positon. For example, the sealing valve assembly  40  is configured to be moved between its open positon and closed person.  FIG.  4    is a vertical cross-sectional view of the filter assembly  1  with the sealing valve assembly  40  in the open position. For example, the vertical cross-sectional view in  FIG.  4    is indicated by line IV-IV in  FIG.  3   . In the open position, the sealing valve assembly  40  is configured to allow fluid f to flow through the sealing valve assembly  40 . In the closed positon (e.g., shown in  FIG.  5   ), the sealing valve assembly  40  is configured to block flow through the sealing valve assembly  40 . 
     As shown in  FIG.  4   , the filter housing  20  includes an internal volume  22  that contains a filter  24 . Dashed lines are provided in  FIG.  4    to illustrate the flow of the fluid f through the filter assembly  1 . In the open position, fluid f from the filter head  90  is allowed to pass through the sealing valve  40  to the filter housing  20 , pass through the filter housing  20 , and then pass from the filter housing  40  through the sealing valve  40  back to the filter head  90 . The open position of the sealing valve  40  is configured to allow the fluid to flow into and out of the internal volume  22  of the filter housing  20 . The filter  24  filters fluid f as it passes through the removable filter cartridge  10 . The fluid f is filtered as it passes through the filter housing  40 , such that the fluid f flowing back to the filter head  20  (and then out through the fluid outlet  4 ) is filtered fluid. 
     The sealing valve assembly  40  has a first end  46  and a second end  48  opposite to the first end  46 . The first end  46  of the sealing valve assembly  40  is coupled to the filter housing  20 . The second end  48  of the sealing valve assembly  40  is configured to removably coupled to the filter head  90 . 
     As shown in the illustrated embodiment, the filter housing  20  may have a bowl shape. The filter housing  20  has an open end  26  and a closed end  28 . The open end  26  and the closed end  28  of the filter housing  20  are opposite ends of the length L of the filter housing  20 . The open end  26  may also be referred to as a fluid inlet-outlet as the fluid f enters and exits the filter housing  20  through its open end  26 . As shown in  FIG.  4   , a first end  46  of the sealing valve  40  is configured to be coupled to the filter housing  20 . The first end  46  of the sealing valve  46  is coupled to the open end  26  of the filter housing  20 . 
     In the illustrated embodiment, the first end  46  of the sealing valve  40  is coupled to the filter housing  20  by threads on the sealing valve  40  and the filter housing  20 . For example, the filter housing  20  is configured to be screwed onto the sealing valve  40  by screwing a coupling nut  30  of the filter housing  20  onto the sealing valve  40 . In an embodiment, the threads of the sealing valve  40  (e.g., threads of the coupling nut  56  of the sealing valve  40 ) and the threads of the filter housing  20  (e.g., threads of the coupling nut  30 ) have the same structure (e.g., thread size, thread spacing, etc.). It should be appreciated that sealing valve  40  in other embodiments may be coupled to the filter housing  20  in a different manner than being screwed together via threads. In another embodiment, the sealing valve  40  and the filter housing  20  may be coupled by, for example but not limited to, clamping (e.g., with a tri-coupler, etc.) or bonding (e.g., thermal bonding of the sealing valve  40  to the filter housing  20 , etc.). 
     The sealing valve  40  is configured to be removably coupled to the filter head  90 . The second end  48  of the sealing valve  40  is removably coupled to the filter head  90 . In the illustrated embodiment, the sealing valve  40  includes threads that screw into threads on the filter head  90  to removably couple the removable filter cartridge  10  to the filter head  90 . As shown in  FIG.  4   , the sealing valve  40  can include a coupling nut  56  with threads that screw onto to the threads of the filter head  90 . It should be appreciated that the sealing valve  40  in other embodiments may be configured to removably couple to the filter head  90  in a different manner than via threads. In an embodiment, the sealing valve  40  may be configured to removably couple to the filter head  90  by, for example but not limited to, via clamping (e.g., with a tri-coupler, or the like). 
     As shown in  FIG.  4   , the sealing valve  40  can include a circumferential groove  58  and a snap ring  60  disposed in the circumferential groove  58  of the valve body  42 . The circumferential groove  58  extends around a circumference of the sealing valve  40 . The snap ring  60  is configured to be compressed between the sealing valve  40  and the filter head  90  when the sealing valve  40  is removably coupled to the filter head  90 . In the illustrated embodiment, the snap ring  60  is compressed between the coupling nut  56  of the sealing valve  40  and the filter head  90  when the coupling nut  56  is screwed onto the filter head  90 . 
     The filter housing  20  includes a first inlet  34 A, a second inlet  34 B, and an outlet  36  provided at the open end  26  of the filter housing  20 . For example, the first inlet  34 A, the second inlet  34 B, and the outlet  36  are different passages extending into the filter housing  20  from the open end  26  (e.g., the open end  26  of the filter housing  20  including the inlets  34 A and outlet  36 ). In the illustrated embodiment, the outlet  36  is disposed radially between the first inlet  34 A and the second inlet  34 B. The filter housing  20  is configured such that the fluid f enters the filter housing  20  through the inlets  34 A,  34 B and exits the filter housing  20  (e.g., after passing through and being filtered by the filter  24 ) through the outlet  36 . It should be appreciated that the filter housing  20  in an embodiment may have a different number of inlets and/or outlets than three. In some embodiments, the filter housing  20  may include one or more inlets  34 A,  34 B and one or more outlets  36 . In an embodiment, the filter housing  20  may include one inlet  34 A and one outlet  34 A. In another embodiment, the filter housing  20  may include two or more inlets  34 A,  34 B and/or two or more outlets  36 . 
     The sealing valve assembly  40  includes passageways  62 A,  62 B that fluidly connect the filter housing  20  and the filter head  90  when the sealing valve assembly  40  is open. As shown in  FIG.  4   , the sealing valve assembly  40  has a valve body  42  that includes the passageways  62 A,  62 B. For example, the valve body  42  includes the first end  46  and the second end  48  of the sealing valve assembly  40 . The passageways  62 A,  62 B extending through the valve body  42 . The fluid f flows through the sealing valve assembly  40  by flowing through the passageways  62 A,  62 B. The sealing valve assembly  40  includes an inlet passageway  62 A that directs fluid f from the filter head  90  into the filter housing  40  and an outlet passageway  62 B that directs the fluid f (after being filtered in the filter housing  20 ) from the filter housing  20  back to the filter head  90 . 
     The valve body  42  includes the passageways  62  for the inlets and outlet(s)  34 A,  34 B,  36  in the open end  26  of the filter housing  20 . Each of the passageways  62  extends through the valve body  42 . Each of the passages  62  extends through the valve body  42  from the first end  46  to the second end  48 . As shown in  FIG.  4   , the passages  62  in the valve body  42  include the inlet passage  62 A and the outlet passageway  62 B that each separately extend through the valve body  42 . In the open position, the inlet passageway  62 A directs the fluid f from the filter head  90  (e.g., fluid to be filtered) to the inlets  34 A,  36 B of the filter housing  20  and the outlet passageway  62 B directs the fluid f (e.g., the filtered fluid) from the outlet  36  of the filter housing  20  to the filter head  90 . The inlet passage  62 A connects the fluid inlet  2  of the filter head  90  (e.g., the passage in the filter head  90  extending from the fluid inlet  2 ) to the inlet(s)  34 A,  34 B of the filter housing  20 . The outlet passage  62 B connects the outlet  36  of the filter housing  20  (e.g., the passage in the filter head  90  extending from the fluid outlet  4 ) to the fluid outlet  4  of the filter head  90 . 
     As shown by the dashed lines in  FIG.  4   , the inlet passageway  62 A fluidly connects the fluid inlet  2  of the filter head  90  to the first and second inlets  34 A,  34 B of the filter housing  20 , and the outlet passageway  62 B fluidly connects the outlet  36  of the filter housing  20  to the fluid outlet  4  of the filter head  90 . For example, the inlet passageway  62 A directs the fluid f supplied from the passage of the fluid inlet  2  of the filter head  90  to the inlets  34 A,  34 B of the filter housing  20 . For example, the outlet passageway  62 B directs the filtered fluid f from the outlet  36  to the passage in the filter head  90  for the fluid outlet  4 . 
     The sealing valve assembly  40  is configured to be actuated between the open position and the closed position by actuating the sealing valves  70 A,  70 B. The sealing valves  70 A,  70 B are gas actuated valves configured to be actuated between their open and closed positions using compressed gas f CP . For example, the compressed gas f CP  is a generally inert gas (e.g., nitrogen, air, filtered air, etc.) that has a pressure greater then ambient pressure. In an embodiment, the pressure of the compressed gas f CP  may be greater than 20 psig. In an embodiment, the pressure of the compressed gas f CP  may be greater than 40 psig. In an embodiment, the pressure of the compressed gas may be from 20 psig-90 psig. 
     In the illustrated embodiment, each of the sealing valves  70 A,  70 B is a gas open valve configured to be closed when not supplied with compressed gas f CP . For example, connecting the removable filter cartridge  10  to the filter head  90  includes removably coupling the removable filter cartridge  10  to the filter head  90  and connecting compressed gas lines  92 A,  92 B to the sealing valves  70 A,  70 B. A first compressed gas line  92 A is connected to an external gas inlet  72 A of the inlet sealing valve  70 A, and a second compressed gas line is connected to an external gas inlet  72 B of the outlet sealing valve  70 B. The first compressed gas line  92 A supplies compressed gas f CP  to the inlet sealing valve  70 A and the second compressed line  92 B supplies compressed gas f CP  to the outlet sealing valve  70 B. 
     The inlet sealing valve  70 A includes the external gas inlet  72 A, a valve housing  74 A, a valve stem  76 A, a valve head  78 A, a spring  80 A, and an internal space  82 A. The external gas inlet  72 A is disposed in the valve housing  74 A and fluidly connects to the internal space  82 A of the inlet sealing valve  70 A. Compressed gas f CP  is supplied to the external gas inlet  72 A to actuate the inlet sealing valve  70  from its closed position (e.g., as shown in  FIG.  5   ) to its open position (e.g., as shown in  FIG.  4   ). The compressed gas f CP  compresses the spring  80 A causing the valve head  78 A to move into its open position. In the open position, the valve head  78 A allows for the fluid f to pass through the inlet passageway  62 A (e.g., does not block the inlet passageway  62 A). 
     For example, the valve head  78 A is disposed on the valve stem  76 A and outside of the valve housing  74 A. The valve stem  76 A extends through a sidewall  84 A of the valve housing  74 A into the inlet passageway  62 A. The spring  80 A is configured to bias the valve head  78 A into a closed position (e.g., shown in  FIG.  5   ) that blocks the inlet passageway  62 A. For example, the valve head  78 A is on the end of the valve stem  76 A, and the spring  80 A biases the valve stem  76 A (e.g., in a first direction D 1 ) into the inlet passageway  62 A which positions the valve head  78 A into its closed position that blocks an opening  63 A (e.g., a valve seat) in the inlet passageway  62 A (e.g., as show in  FIG.  5   ). 
     In the illustrated embodiment, the compressed gas f CP  is supplied to the internal space  82 A through the external gas inlet  72 A. The internal space  82 A is filled with the compressed gas f CP  (e.g., internal space  82 A is pressurized from a first pressure P 1  to a second pressure P 2 ) The compressed gas in the internal space  82 A compresses the spring  80 A which retracts the valve head  78 A from the inlet passageway  62 A actuating the inlet sealing valve  70 A from its closed position to its open position (shown in  FIG.  4   ). For example, as shown in  FIG.  4   , the spring  80 A is affixed to the valve plate  86 A and is configured to bias the valve head  78 A in a first direction D 1 . The compressed gas in the internal space  82 A pushes the valve plate  86 A in the opposite direction (e.g., second direction D 2 ) which compresses the spring  80 A and overcomes the biasing force of the spring  80 A on the valve head  78 A. This moves the valve head  78 A away from the opening  63 A in the inlet passageway  62 A (e.g., moves the valve head  78 A in direction D 2  towards the sidewall  84 A of the inlet sealing valve  70 A) such that the valve head  78 A no longer blocks the opening  63 A/inlet passageway  62 A. 
     For simplicity, the configuration of the inlet sealing valve  70 A is discussed above. It should be appreciated that the outlet sealing valve  70 B can have a similar configuration as described for the inlet sealing valve  70 A except with respect to blocking the outlet passageway  62 B. 
     It should be appreciated that the filter housing  20  in other embodiments may have a different number of inlets and outlets  34 A,  34 B,  36  at its open end  26  than three (e.g., one inlet, more than two inlets, multiple outlets etc.). In an embodiment, the sealing valve assembly  40  (e.g., the valve body  42 ) may have a different number of inlet and outlet passageways  62 A,  62 B than two (e.g., same number of corresponding passages as inlets and outlets in the filter housing  20 , etc.). For example, the valve body  42  in an embodiment may include a second inlet passageway  62 A for separately directing a portion of the fluid f to be filtered to the second inlet  34 B of the filter housing  20 , and the sealing valve assembly  40  including a second inlet sealing valve  70 A for the second inlet passageway  62 A. 
       FIG.  5    is a vertical cross-sectional view of the filter assembly  1  with the sealing valve assembly  40  in the closed position. For example, the vertical cross-section of  FIG.  5    is along the line VI-VI in  FIG.  3   .  FIG.  5    is similar view to  FIG.  4    except that the sealing valve assembly  40  is moved to its closed position. The sealing valve assembly  40  in the closed position is configured to block fluid f from flowing through the filter assembly  1 . 
     As shown in  FIG.  5   , the sealing valve assembly  40  in its closed positon blocks the fluid from passing through the seal valve assembly  40  between filter housing  20  and the filter heat  90  (e.g., blocks fluid flow from the filter head  90  to the filter housing  20  and blocks fluid flow from the filter housing  20  to the filter head  90 ). The removable filter cartridge  10  is configured to have the seal valve assembly  40  actuated to the closed position while still removably coupled to the filter head  90 . The sealing valve assembly  40  is closed by no longer supplying compressed gas to the sealing valves  70 A,  70 B (e.g., no longer applying compressed gas to the sealing valve  70 A,  70 B). The sealing valves  70 A,  70 B are moved to their closed position by decompressing the internal spaces  82 A,  82 B of the sealing valves  70 A,  70 B. For example, the internal space  82 A of the inlet sealing valve  70 A may be decompressed into the ambient environment by disconnecting the compressed gas line  92 A from its external gas inlet  72 A. 
     When the removable filter cartridge  10  is uncoupled from the filter head  90  (e.g., the coupled filter housing  20  and sealing valve assembly  40  are uncoupled/unscrewed from the filter head  90 ), the sealing valve assembly  40  is configured to maintain the sealing of the internal volume  22 . For example, without the supply of compressed gas, the sealing valves  70 A,  70 B remain closed and seal the filter housing  20 . The sealing valve assembly  40  is configured to maintain the sealing of the filter housing  20  while the filter cartridge  10  remains uncoupled from a filter head  90 . In particular, the closing of the sealing valve assembly  40  seals the filter housing  20  such that any of the liquid in the internal volume  22  is trapped within the removable filter cartridge  10 . This is advantageous over previous configuration in that the removable filter cartridge  10  can be removed more quickly without having to be drained of liquid. 
       FIGS.  6  and  7    show another embodiment of a filter assembly  101 .  FIG.  6    is a side perspective view of the filter assembly  101 .  FIG.  7    is an exploded view of the filter assembly  101 . The filter assembly  101  includes a removable filter cartridge  110  that is coupled to a filter head  190  and includes a filter housing  120  and a sealing valve assembly  140 . The filter assembly  101  generally has a similar configuration to the filter assembly  1  in  FIGS.  1 - 5    except for the sealing valve assembly  140 . For example, the filter head  90  includes a fluid inlet  102  and a fluid outlet of the filter assembly  101  and is configured to supply the fluid through the removable filter cartridge  110 ; and the removable filter cartridge  110  filters the fluid passing that passes through similar to the removable filter cartridge  1  in  FIG.  1   . For example, the sealing valve assembly  140  has a first end  146  coupled to the filter housing  120  and a second end  148  removably coupled to the filter head  90 . The filter assembly  101  can have features similar to the filter assembly  1  in  FIGS.  1 - 5    unless described otherwise. 
     The filter housing  120  and the filter head  190  have a similar configuration to the filter head  90  and filter housing  20  of the filter assembly  1  in  FIGS.  1 - 5   . It should be appreciated that the filter housing  120  and/or the filter head  190  may be different in other embodiments as similarly described for the filter housing  20  and the filter head  90  in  FIGS.  1 - 5   . As shown in  FIG.  7   , the filter assembly  101  includes a push rod  192  for actuating the sealing valve assembly  140 . The push rod  192  will be discusses in more detail below. 
     The sealing valve assembly  140  has an open position and a closed position. In the open position, the sealing valve assembly  140  is configured to allow fluid to flow through the sealing valve assembly  140 . In the closed positon, the sealing valve assembly  140  is configured to block flow through the sealing valve assembly  140 . The sealing valve assembly  140  has a first end  146  and a second end  148  opposite to the first end  146 . For example, a valve body  142  of the sealing valve assembly  140  includes the first end  146  and the second end  148  of the sealing valve assembly  140 . 
     The sealing valve assembly  140  is configured to be removably coupled to the filter head  190  as similarly discussed for the sealing valve  40  and filter head  90  in  FIGS.  1 - 8   . In the illustrated embodiment, the second end  148  of the sealing valve assembly  140  is removably coupled to the filter head  190  via a coupling nut  156  of the sealing valve assembly  140 . The sealing valve assembly  140  can include the coupling nut  156  and a snap ring  160  (shown in  FIG.  8   ) for coupling the sealing valve assembly  140  to the filter head  190 . For example, the threads of the coupling nut  156  are screwed into threads on the filter head  190 . In an embodiment, the sealing valve assembly  140  may be configured to removably couple to the filter head  190  by, for example but not limited to, a coupler (e.g., a tri-coupler, or the like). 
     As shown in  FIG.  8   , the filter housing  120  includes a first inlet  134 A, a second inlet  134 B, and an outlet  136  provided at the open end  126  of the filter housing  120  similar to the filter housing  120  in  FIGS.  1 - 5   . The filter housing  120  is configured such that the fluid f enters the filter housing  120  through the inlets  134 A,  134 B and exits the filter housing  120  (e.g., after passing through and being filtered by the filter  124 ) through the outlet  136 . It should be appreciated that the filter housing  120  in an embodiment may have a different number of inlets and/or outlets than three as similarly discussed for the filter housing  20  in  FIGS.  1 - 5   . 
     The sealing valve assembly  140  includes passageways  162 A,  162 B,  162 C that fluidly connect the filter housing  120  and the filter head  190  when open. As shown in  FIG.  8   , the sealing valve assembly  140  has the valve body  142  that includes the passageways  162 A,  162 B,  162 C. The passageways  162 A,  162 B,  162 C extend through the valve body  42 . The fluid f flows through the sealing valve assembly  140  by flowing through the passageways  162 A,  162 B,  162 C. The sealing valve assembly  140  includes a first inlet passageway  162 A and a second inlet passageway  162 B that directs fluid f from the filter head  190  into the filter housing  140  and an outlet passageway  162 C that directs the fluid f (after being filtered in the filter housing  120 ) from the filter housing  120  back to the filer head  190 . In an embodiment, the sealing valve assembly  140  may include a different number of inlet passageways  162 A,  162 B (e.g., one inlet passageway, etc.) and/or outlet passageways  162 C (e.g., multiple outlet passageways, two outlet passageways, etc.) 
     The valve body  142  includes the passageways  162  for the inlets and outlet(s)  134 A,  134 B,  136  in the open end  126  of the filter housing  120 . Each of the passageways  162  extends through the valve body  142 . As shown in  FIG.  8   , the passageways  162  in the valve body  142  include the inlet passageways  162 A,  162 B and the outlet passageway  162 C that separately extend through the valve body  142 . In the illustrated embodiment, the inlet passageways  162  merge within the valve body  142  at the first end  146  such that the fluid f flowing through the inlet passageways  162 A,  162 B mixes and is supplied to both inlets  134 A,  134 B of the filter housing  120 . In the open position, the inlet passageways  162 A,  162 B direct the fluid f from the filter head  190  (e.g., fluid to be filtered) to the inlets  134 A,  136 B of the filter housing  120  and the outlet passageway  162 C directs the fluid f (e.g., the filtered fluid) from the outlet  136  of the filter housing  120  to the filter head  190 . The inlet passageways  162 A,  162 B each connect the fluid inlet  102  of the filter head  190  (e.g., the passage in the filter head  90  extending from the fluid inlet  102 ) to the inlet(s)  134 A,  134 B of the filter housing  120 . The outlet passage  162 B connects the outlet  136  of the filter housing  120  (e.g., the passageway in the filter head  190  extending to the fluid outlet  104 ) to the fluid outlet  104  of the filter head  190 . 
     As shown by the dashed lines in  FIG.  8   , the inlet passageways  162 A,  162 B fluidly connect the fluid inlet  102  of the filter head  190  to the first and second inlets  134 A,  134 B of the filter housing  120 , and the outlet passageway  162 B fluidly connects the outlet  136  of the filter housing  120  to the fluid outlet  104  of the filter head  190 . For example, the inlet passageways  162 A direct the fluid f supplied from the passage of the fluid inlet  102  of the filter head  190  to the inlets  134 A,  134 B of the filter housing  120 . For example, the outlet passageway  162 B directs the filtered fluid f from the outlet  136  to the passage in the filter head  190  for the fluid outlet  104 . 
     The sealing valves include an inlet sealing valve  170 A configured to block flow of liquid into the filter housing  120  (e.g., from the filter head  190 ) and an outlet sealing valve  170 B configured to block flow of liquid out of the filter housing  120  (e.g., to the filter head  190 ). The sealing valve assembly  140  is configured to be actuated between the open position and the closed position by actuation of the sealing valves  170 A,  170 B from their open position to their closed position. In the illustrated embodiment, the inlet sealing valve  170 A is a fluid check valve configured to be actuated between its open and closed positions by the pressure of the fluid f supplied from the filter head  190 , and the outlet sealing valve  170 B is a push valve configured to be actuated between its open and closed positions by the push rod  192  when the removable filter cartridge  120  (e.g., the sealing valve assembly  140 ) is removably coupled to the filter head  190 . 
     The inlet sealing valve  170 A is a fluid check valve that is configured to be actuated by the fluid f pushing on the inlet sealing valve  170 A. When no fluid is pushing on the inlet sealing valve  170 A (e.g., the filter head  190 A is not supplying fluid to the sealing valve assembly  140 , the removable filter cartridge  110  being uncoupled from the filter head  190 A, etc.), the inlet sealing valve  170 A is in its closed position. The default position of the inlet sealing valve  170 A is its closed position. The inlet sealing valve  170 A is configured to move from its closed position to its open position when the filter head  190  supplies a flow of fluid f to the sealing valve assembly  140 . 
     In the illustrated embodiment, the inlet sealing valves  170 A includes a backstop  174 A, a valve head  178 A, and a spring  180 A disposed between the backstop  174 A and the valve head  178 A. In the illustrated embodiment, the valve head  178 A has a planar torus shape that encircles the outlet passageway  162 C. The backstop  174 A is affixed to the valve body  142 . In an embodiment, the backstop  174 A may be formed as an integral part of the valve body  142 . The valve head  178 A is configured to be moveable relative to the valve body  142 . 
     The spring  180 A is configured to bias the valve head  178 A into its closed position (e.g., as shown in  FIG.  9   ) that blocks the inlet passageways  162 A. For example, the spring  180 A biases/pushes the valve head  178 A (e.g., in direction D 3 ) into its closed position that blocks the inlet passageways  162 A,  162 B (e.g., as show in  FIG.  9   ). The pressure of the fluid f pushes the valve head  178 A pushes the valve head  178 A in the opposite direction (e.g., direction D 4 ) from its closed position into its open position as shown in  FIG.  8   . The pressure of the fluid f on the valve head  178 A overcomes the biasing force of the spring  180 A and compresses the spring  180 A to move the valve head  178 A into its open position. 
     The outlet sealing valve  170 B is a push valve configured be actuated by a push rod  192  from its open position (shown in  FIG.  8   ) to its closed position (shown in  FIG.  9   ) when the removable filter cartridge  110  is removably coupled to the filter head  190 . The removable coupling of the sealing valve assembly  140  to the filter head  190  moves the outlet sealing valve  170 B from its closed position to its open position. 
     In the illustrated embodiment, the outlet sealing valve  170 B includes a backstop  174 B, a valve head  178 B, and a spring  180 B disposed between the backstop  174 B and the valve head  178 B. The backstop  174 B is affixed to the valve body  142 . In another embodiment, the backstop  174 B may be formed as an integral part of the valve body  142 . The valve head  178 B is configured to be moveable relative to the valve body  142 . In the illustrated embodiment, the valve head  178 B has a continuous planar shape. 
     As shown in  FIG.  8   , in the assembled filter assembly  101 , the push rod  192  is disposed between the sealing valve  40  and the filter head  190 . More specifically, the push rod is disposed in the filter head  190  and extends into the valve body  142  of the sealing valve assembly  140 . The push rod  192  include a first end  194  and a second end  196 . The first end  194  of the push rod  192  is disposed in the filter head (e.g., the passageway in the filter head  190  extending to the fluid outlet  104 ) and the second end  196  of the push rod  192  is disposed in the outlet passageway  162 C. The first end  194  of the push rod  192  directly contacts the filter head  190  and a second end  196  of the push rod  192  directly contacts the filter head  190 . As shown  FIG.  8   , the filtered fluid f flowing from the outlet passage  162 C to the outlet  104  of the filter head  190  flows through the first end  194  of the push rod  192  (e.g., flows through one or more through holes in the second end  194  of the push rod  192 ). 
     The spring  180 B is configured to bias the valve head  178 B into its closed position (e.g., as shown in  FIG.  9   ) that blocks the outlet passageway  162 C. For example, the spring  180 B biases/pushes the valve head  178 B (e.g., in direction D 3 ) into its closed position that blocks the outlet passageway  162 C (e.g., as show in  FIG.  9   ). When the sealing valve assembly  40  is removably coupled to the filter head  190 , the push rod  192  is compressed between the valve head  178 B and the filter head  190 . As the push rod  192  is generally incompressible, the push  192  forces the valve head  178 B upward from its closed position to its open position as shown in  FIG.  8   . As shown in  FIG.  8   , when the sealing valve assembly  40  is removably coupled to the filter head  190 , the push rod  192  compresses the spring  180 B. Through the push rod  192 , the filter head  190  pushes on the valve head  178 B and moves/actuates the valve head  178 B into its open position. The pressure/force of the push rod  192  on the valve head  178 B pushes the closed valve head  178 B in the opposite direction (e.g., direction D 4  that is away from the filter head  190 ) into its open position as shown in  FIG.  8   . The upward force on the valve head  178 B overcomes the biasing force of the spring  180 B and compresses the spring  180 B to move the valve head  178 B into its open position. 
     As discussed above, the filter cartridge  110  (e.g., the sealing valve assembly  140 ) is removably coupled to the filter head  190 .  FIG.  9    is a vertical cross-sectional view of the filter cartridge  140  when uncoupled from the filter head  190 . The cross-section in  FIG.  9    is along the same plane as  FIG.  8   . 
       FIG.  9    shows the sealing valve assembly  140  when closed. The sealing valve assembly  140  actuates from open (as shown in  FIG.  8   ) to closed (as shown in  FIG.  9   ) during the uncoupling of the filter cartridge  110  (e.g. the sealing valve assembly  140 ) from the filter head  190 . The actuating of the sealing valve assembly  140  from open to closed includes actuating the inlet sealing valve  170 A from its open position to its closed position and actuating the outlet sealing valve  170 B from its open position to its closed position. The inlet sealing valve  170 A closes when fluid f is no longer being suppled into the sealing valve assembly  170 A from the filter head  190 . When uncoupled from the filter head  110 , the filter head  190  is no longer fluidly connected to the filter cartridge  110  such that fluid is no longer being supplied to the filter cartridge  100 . Generally, the flow of fluid f to the filter cartridge  110  is configured to stop prior to the uncoupling of the filter cartridge  110  from the filter head  190 . In such a configuration, the inlet sealing valve  170 A may actuate to its closed position prior to the actual action of uncoupling the filter cartridge  110  from the filter head  190 . 
     The actuation of the outlet sealing valve  170 B from its open position to its closed position occurs during the uncoupling of the filter cartridge  110  (e.g., the sealing valve assembly  140 ) from the filter head  110 . During the uncoupling of the filter cartridge  110 , the second end  148  of the sealing valve assembly  140  is moved away from the filter head  110  (e.g., in direction D 4 ). As the distance between the second end  146  of the sealing valve assembly  140  and the filter head  190  increases, the push rod  192  no longer leverages/pushes the valve head  178 B upwards (e.g., in direction D 3 ) and the spring  180 B pushes the valve head  178 B back into its closed position. In an embodiment, the push rod  192  has a length that results in the valve head  178 B being moved to its closed position (as shown in  FIG.  9   ) during the uncoupling before the sealing valve  140  becomes completely uncoupled (e.g., the valve head  178 B moved into its closed position while the sealing valve  140  is still partially screwed onto the filter head  190 ). 
       FIG.  9    shows the inlet sealing valve  170 A and its valve head  178 A in its closed position. The valve head  178 A of the inlet sealing valve  170 A in its closed position blocks the inlet passageways  162 A,  162 B by extending over and blocking the openings  163 A,  163 B in the valve body  162 A for the inlet passageways  162 A,  162 B. In its closed position, the valve head  178  is pressed against the valve body  142  (e.g., an inner surface of the valve body  142 ) and seals the openings  163 A,  163 A in the valve body  142  for the inlet passageways  162 A,  162 B. 
       FIG.  9    shows the outlet sealing valve  170 B and its valve head  178 A in its closed position. The valve head  178 B of the outlet sealing valve  170 B in its closed position blocks the outlet passageway  162 C by extending over and blocking an opening  162 C in the valve body  142  for the outlet passageway  162 C. In its closed position, the valve head  178 B is pressed against the valve body  142  (e.g., an inner surface of the valve body  142 ) and seals the opening  163 C in the valve body  142  for the outlet passageway  162 C. For example, the outer circumference of the valve head  178  is in direct contact with the valve body  142  in the closed position. 
     In the illustrated embodiment, the push rod  192  is shown as a separate piece from the sealing valve  140  and the filter head  190 . In an embodiment, the filter head  190  may include the push rod  192  as a separate piece as shown in  FIGS.  7  and  8   . In an embodiment, the push rod  192  may be an integral piece of the filter head  190  (e.g., the filter head  190  formed to include the push rod  192 , the end  194  of the push rod  192  affixed to the filter head  190 , etc.). In another embodiment, the push rod  192  may be provided with the sealing valve assembly  140 . For example, the push rod  192  may be provided as a separate piece of the sealing valve assembly  140  or as an integral piece of the outlet sealing valve  170 B (e.g., the valve head  178 B formed to include the push rod  192 , the end  196  of the push rod  192  affixed to the valve head  178 B). 
     When the removable filter cartridge  110  is uncoupled from the filter head  190  (e.g., the coupled filter housing  120  and sealing valve assembly  140  are uncoupled/unscrewed from the filter head  90 ), the sealing valve assembly  140  is configured to maintain the sealing of the internal volume  122 . The sealing valve assembly  140  is configured to maintain the sealing of filter housing  120  while the cartridge remains uncoupled from a filter head. In particular, the closing of the sealing valve assembly  140  seals the filter housing  120  such that any of the liquid in the internal volume  122  is trapped within the removable filter cartridge  110 . This is advantageous over previous configuration in that the removable filter cartridge  110  can be removed more quickly without having to be drained of liquid. 
     It should be appreciated that an embodiment of a sealing valve assembly may include an inlet check valve and an outlet check valve that are selected from different combinations then disclosed in  FIGS.  1 - 9   . In an embodiment, a sealing valve assembly may include an inlet sealing valve that is one of a gas open valve (e.g., inlet sealing valve  70 A), a fluid check valve (e.g., inlet check valve  170 A), and a push valve; and an outlet sealing valve that is one of a gas open valve (e.g. outlet sealing valve  70 B), a fluid check valve, and a push valve (e.g., outlet check valve  170 B). For example, a sealing valve assembly in an embodiment may include an inlet sealing valve that is a gas open valve (e.g., inlet sealing valve  70 A) and an outlet check valve that is a push valve (e.g., outlet check valve  170 B). For example, a sealing valve assembly in an embodiment may include an inlet sealing valve that is a fluid check valve (e.g., inlet check valve  170 A) and an outlet sealing valve that is a gas open valve (e.g., outlet sealing valve  170 B). 
       FIG.  10    shows a block flow diagram of a method  1000  of retrofitting a filter housing (e.g., filter housing  20 , filter housing  120 ). The filter housing has an internal volume (e.g., internal volume  22 , internal volume  122 ) containing a filter (e.g., filter  24 , filter  124 ). For example, the method  1000  may be for retrofitting a filter housing (e.g., filter housing  120 ) that was originally intended to be directly removably coupled to a filter head (e.g., filter header  90 , filter head  190 ). The method starts at  1010 . 
     At  1010 , the filter housing is uncoupled from the filter head. Removing the filter housing from the filter head  1010  includes uncoupling an open end of the filter housing (e.g., open end  26 , open end  126 ) from the filter head. In an embodiment, uncoupling the filter housing from the filter head  1010  may include unscrewing the filter housing form the filter head  1012 . For example, unscrewing the filter housing from the filter head can include unscrewing a coupling nut of the filter housing (e.g., coupling nut  30 , coupling nut  130 ) from the filter head. The method  1000  then proceeds to  1020 . 
     At  1020 , a first end (e.g., first end  46 , first end  146 ) of a sealing valve (e.g., sealing valve assembly  40 , sealing valve assembly  140 ) is coupled to the removable filter to form a removable filter cartridge (e.g., removable filter cartridge  10 , removable filter cartridge  110 ). In an embodiment, coupling the sealing valve to the removable filter  1020  includes screwing together the filter housing and the sealing valve  1022 . For example, screwing together the filter housing and the sealing valve  1022  can include screwing the coupling nut of the filter housing onto the sealing valve. The method  1000  then proceeds to  1030 . 
     At  1030 , the removable filter cartridge is removably coupled to the filter head. Removably coupling the cartridge to the filter head  1030  includes removably coupling a second end of the sealing valve (e.g., second end  48 , second end  148 ) to the filter head. In an embodiment, removably coupling the removable filter cartridge to the filter head at  1030  may include screwing the removable filter cartridge onto the filter head  1032 . For example, screwing the removable filter cartridge onto the filter head at  1032  may include screwing a coupling nut of the sealing valve (e.g., coupling nut  56 , coupling nut  156 ) onto the filter head. The method  1000  then proceeds to  1040 . 
     At  1040 , the sealing valve assembly is actuated from closed (e.g., sealing valve assembly  40  in  FIG.  5   , sealing valve assembly in  FIG.  9   ) to open (e.g., sealing valve assembly  40  in  FIG.  4   , sealing valve assembly in  FIG.  8   ). The actuation of the sealing valve assembly at  1040  can include actuating an inlet sealing valve of the sealing valve assembly  1042  (e.g., inlet sealing valve  70 A, inlet sealing valve  170 A) and actuating an outlet sealing valve of the sealing valve assembly  1042  (e.g., outlet sealing valve  70 B, outlet sealing valve  170 B). 
     In an embodiment, the inlet check valve can be a gas open valve (e.g., inlet check valve  70 A) and actuating the inlet sealing valve at  1042  can include supplying compressed gas to an external gas inlet of the inlet sealing valve (e.g., external gas inlet  72 A) to actuate the inlet check valve from a closed position to an open position. In an embodiment, the inlet check valve can be a fluid check valve (e.g. inlet check valve  170 A) and actuating the inlet sealing valve at  1042  can include the filter head supplying liquid (e.g., fluid f in  FIG.  8   ) from the filter head to the inlet passageway of the sealing valve and the pressure of the liquid in the inlet passageway on the inlet sealing valve actuates the inlet sealing valve from the closed position to the open position. In an embodiment, the outlet check valve can be a gas open valve (e.g., outlet check valve  70 B) and actuating the outlet sealing valve at  1044  can include supplying compressed gas to an external gas inlet of the outlet sealing valve to actuate the outlet check valve from a closed position to an open position. In an embodiment, the outlet check valve can be a push valve and actuating the outlet sealing valve at  1044  can include the filter head pushing, via a push rod (e.g., push rod  192 ), a filter head of the outlet check valve (e.g., filter head  178 B) from a closed position to an open position. In such an embodiment, the actuating of the outlet sealing valve at  1044  can occur during the removably coupling of the sealing valve to the filter head (e.g., removable coupling of the filter cartridge to the filter head at  1030  including the actuating of the outlet sealing valve  1044 ). 
     It should be appreciated that the method  1000  in an embodiment may be modified to include features as described above with respect to the filter assembly  1  in  FIGS.  1 - 5    and/or the filter assembly  101  in  FIGS.  6 - 9   . 
     Aspects: 
     Any of Aspects 1-11 can be combined with any of Aspects 12-19, and any of Aspects 12-15 can be combined with any of Aspects 16-19. 
     Aspect 1. A removable filter cartridge, comprising: a filter housing with an internal volume containing a filter, the filter configured to filter liquid passing through the internal volume, the filter housing including an open end with an inlet and an outlet; and a sealing valve assembly including: a first end configured to removably couple the sealing valve assembly to a filter head, a second end coupled to the open end of the filter housing, an inlet passageway configured to direct liquid into the inlet of the filter housing, an outlet passageway configured to direct the liquid discharged from the outlet of the filter housing after being filtered by the filter, and an inlet sealing valve configured to block the inlet passageway and an outlet sealing valve configured to block the outlet passageway when the sealing valve assembly is uncoupled from the filter head such that the internal volume is sealed while the removable filter cartridge is uncoupled from the filter head. 
     Aspect 2. The removable filter cartridge of Aspect 1, wherein the inlet sealing valve is one of a gas open valve, a fluid check valve, and a push valve, and the outlet sealing valve is one of a gas open valve, a fluid check valve, and a push valve. 
     Aspect 3. The removable filter cartridge of any one of Aspects 1 and 2, wherein the inlet sealing valve is a gas open valve, the inlet sealing valve including a valve head, a spring biasing the valve head into a closed position that blocks the inlet passageway, and an external gas inlet for supplying compressed gas into the inlet sealing valve. 
     Aspect 4. The removable filter cartridge of Aspect 3, wherein the inlet sealing valve is configured to be actuated from the closed position to an open position by the compressed gas supplied through the external gas inlet. 
     Aspect 5. The removable filter cartridge of any one of Aspects 3 and 4, wherein the inlet sealing valve includes an internal space fluidly connected to the external gas inlet, the external gas inlet configured to direct the compressed gas into the internal space to compress the spring and actuate the valve head into an open position. 
     Aspect 6. The removable filter cartridge of any one of Aspects 3-5, wherein the sealing valve assembly includes a valve body, the valve body including the inlet passageway and the outlet passageway, and the inlet sealing valve and the outlet sealing valve each being coupled to the valve body. 
     Aspect 7. The removable filter cartridge of any one of Aspects 1-6, wherein the outlet sealing valve is a gas open valve, the outlet sealing valve includes an external gas inlet, and the outlet sealing valve configured to be actuated from a closed position to an open position by compressed gas supplied to the filter cartridge through the second external gas inlet. 
     Aspect 8. The removable filter cartridge of any one of Aspects 1-6, wherein the outlet sealing valve is a push valve configured to actuate from a closed position that blocks the outlet passageway to an open position by the removable coupling of the sealing valve assembly to the filter head. 
     Aspect 9. The removable filter cartridge of Aspect 8, wherein the outlet sealing valve is configured to be actuated from the closed position to the open position by a push rod disposed between the sealing valve and the filter head when the sealing valve is removable coupled to the filter head. 
     Aspect 10. The removable filter cartridge of Aspect 9, wherein the outlet sealing valve includes a valve head and a spring biasing the valve head into the closed position that blocks the outlet passageway, the push rod configured to push the valve head into the open position during the removable coupling of the removable filter cartridge to the filter head. 
     Aspect 11. The removable filter cartridge of any one of Aspects 7-10, wherein the inlet sealing valve is a fluid check valve configured to be actuated from a closed position that blocks the inlet flow passage to an open position by the filter head supplying the liquid to the inlet passageway. 
     Aspect 12. A sealing valve assembly for a removable filter cartridge, the sealing valve comprising: a first end configured to removably couple the sealing valve assembly to a filter head; an inlet passageway and an outlet passageway that each extend through the sealing valve assembly; a second end configured to couple the sealing valve assembly to a filter housing to form the removable filter cartridge such that the inlet passageway directs liquid into an inlet of the filter housing and the outlet passageway directs the liquid discharged from an outlet of the filter housing after passing through the filter housing, the filter housing including an internal volume and a filter configured to filter the liquid passing through the filter housing; and an inlet sealing valve configured to block the inlet passageway and an outlet sealing valve configured to block the outlet passageway when the sealing valve assembly is uncoupled from the filter head such that the internal volume is sealed while the removable filter cartridge is uncoupled from the filter head. 
     Aspect 13. The sealing valve assembly of Aspect 12, wherein the inlet sealing valve is a gas open valve, the inlet sealing valve including an external gas inlet for supplying compressed gas into the inlet sealing valve to actuate the inlet sealing valve from a closed position that blocks the inlet passageway to an open position. 
     Aspect 14. The sealing valve assembly of any one of Aspects 12 and 13, wherein the outlet sealing valve is a gas open valve, the outlet sealing valve including a second external gas inlet for supplying compressed gas into the outlet sealing valve to actuate the outlet sealing valve from a closed position that blocks the outlet passageway to an open position. 
     Aspect 15. The sealing valve assembly of any one of Aspects 12 and 13, wherein the outlet sealing valve is a push valve configured to be actuated by a push rod from a closed position that blocks the outlet passageway to an open position by the removable coupling of the sealing valve assembly to the filter head. 
     Aspect 16. A method of retrofitting a filter housing, the filter housing having an internal volume containing a filter configured to filter liquid, the method comprising: removing the filter housing from a filter head, which includes uncoupling the filter housing from the filter head; coupling a sealing valve assembly to the filter housing to form a removable filter cartridge, which includes coupling a first end of the sealing valve assembly to an open end of the filter housing; coupling the removable filter cartridge to the filter head, which includes coupling a second end of the sealing valve assembly to the filter head, wherein the sealing valve assembly includes: an inlet passageway that directs liquid from the filter head into an inlet of the filter housing, an outlet passageway that directs the liquid discharged from an outlet of the filter housing after passing through the filter to the filter head, and an inlet sealing valve configured to block the inlet passageway and an outlet sealing valve configured to block the outlet passageway when the sealing valve assembly is uncoupled from the filter head such that the internal volume is sealed while the removable filter cartridge is uncoupled from the filter head. 
     Aspect 17. The method of Aspect 16, further comprising: supplying compressed gas to an external gas inlet of the inlet sealing valve to actuate the inlet sealing valve from a closed position that blocks the inlet passageway to an open position that allows the liquid to pass through the inlet passageway, the inlet sealing valve being a gas open valve. 
     Aspect 18. The method of any one of Aspects 16 and 17, wherein the coupling of the removable filter cartridge to the filter head includes the filter head pushing, via a push rod, a valve head of the outlet sealing valve from a closed position that blocks the outlet passageway into an open position that allows the liquid to pass through the outlet passageway. 
     Aspect 19. The method of any one of Aspects 16 and 18, further comprising: supplying the liquid from the filter head to the inlet passageway of the sealing valve, a pressure of the liquid in the inlet passageway on the inlet sealing valve actuating the inlet sealing valve from a closed position that blocks the inlet passageway to an open position. 
     The examples disclosed in this application are to be considered in all respects as illustrative and not limitative. The scope of the invention is indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.