Patent Description:
Embodiments of the present disclosure are generally related to pitless adapters for groundwater heat exchangers that are submersed within groundwater of a well or a borehole for use by a heating and/or cooling system.

Heating and cooling systems generally move thermal energy from one location to another, such as moving thermal energy from a heat source to a heat sink (for example, a region of higher temperature to a region of lower temperature), or from a heat sink to a heat source (for example, a region of lower temperature to a region of higher temperature). Some heating and cooling systems utilize a heat pump. Heat pumps perform a refrigeration cycle using a circulating refrigerant to move heat through evaporation (heat absorption) and condensation (heat rejection) phases. The evaporation and condensation phases of the refrigerant typically takes place in two different units called the evaporator and condenser, respectively. In a heat pump, the evaporator is switched to be a condenser and vice versa depending on whether cooling or heating is required.

Geothermal or ground source heat pumps use the earth as a heat source or heat sink. A heat exchanger is positioned underground to provide cooling by using the earth as a heat sink, or to provide heating by using the earth as a heat source. The ground loops of most traditional geothermal heat pump systems focus on heat exchange via conduction with subsurface rocks and sediments, and do not systematically take advantage of heat exchange with flowing or stationary groundwater.

<CIT> and PCT international application number <CIT> disclose groundwater heat exchangers that are used within a well, a geothermal borehole, etc., to exchange heat with the earth and/or groundwater. The well, borehole, etc., may be installed vertically, horizontally, or at any angle between, and it may be cased with pipe, uncased, partially cased, screened, unscreened, or any combination thereof.

<CIT> discloses a pitless adapter comprising: a casing comprising a first port, a second port and a third port; and a spool removably received within an interior cavity of the casing, the spool including: a top plate; a bottom plate; a first port and a second port in the bottom plate.

The present disclosure relates to a pitless adapter having three ports as defined in claim <NUM> for handling the exchange of the loop fluid flows between a heat pump and the one or more groundwater heat exchangers, a system that utilizes this pitless adapter acccording to claim <NUM> as well as a system according to claim <NUM> utilizing a pitless adapter having two ports as defined in that claim. The pitless adapter used in the system according claim <NUM> includes a casing and a spool, which is removably received within an interior cavity of the casing. The casing includes a first port and a second port. The spool includes a top plate, a bottom plate, and a middle plate between the top and bottom plates. The bottom plate includes a first port and a second port. The casing, the top plate and the middle plate define a first chamber that is open to the first port of the casing and the first port of the spool. The casing, the middle plate and the bottom plate define a second chamber that is open to the second port of the casing and the second port of the spool. A first fluid pathway extends from the first port of the spool through the second chamber and the middle plate to the first chamber. A second fluid pathway extends from the second port of the spool to the second chamber.

In some embodiments of the pitless adapter used in the system of claim <NUM>, the spool includes a first tube extending from the bottom plate at the first port of the spool to the middle plate, and the first fluid pathway extends through the first tube. The first tube may include a perforated tubing section extending between the middle plate and the top plate and into the first chamber, and the first fluid pathway may extend through the perforated tubing section of the first tube.

The spool may include a second tube including a perforated tubing section extending from the bottom plate at the second port of the spool through the second chamber to the middle plate, and the second fluid pathway extends through the perforated tubing section of the second tube. The second tube may extend from the middle plate, through the first chamber to the top plate.

In some embodiments of the pitless adapter used in the system of claim <NUM>, the spool includes at least one pass-through tube extending from an opening in the top plate through an opening in the middle plate to an opening in the bottom plate.

The top plate, the middle plate and the bottom plate may each include an annular groove, and the pitless adapter may include an O-ring in each annular groove that forms a seal between the corresponding plate and an interior wall of the casing.

In some embodiments of the pitless adapter used in the system of claim <NUM>, the casing includes a cylindrical wall, and the first port and the second port of the casing each include an opening in the cylindrical wall.

The pitless adapter according to claim <NUM> which is used in the system according to claim <NUM> includes a casing and a spool, which is removably received within an interior cavity of the casing. The casing includes a first port, a second port and a third port. The spool includes a top plate, a bottom plate, a first middle plate between the top and bottom plates, and a second middle plate between the first middle plate and the bottom plate. The bottom plate includes first, second and third ports. The casing, the top plate and the first middle plate define a first chamber that is open to the first port of the casing and the first port of the spool. The casing, the first middle plate and the second middle plate define a second chamber that is open to the second port of the casing and the second port of the spool. The casing, the second middle plate and the bottom plate define a third chamber that is open to the third port of the casing and the third port of the spool. A first fluid pathway extends from the first port of the spool through the third chamber, the second middle plate, the second chamber, and the first middle plate to the first chamber. A second fluid pathway extends from the second port of the spool through the third chamber, and the second middle plate to the second chamber. A third fluid pathway extends from the third port of the spool to the third chamber.

In some embodiments of the pitless adapter according to claim <NUM>, the spool includes a first tube extending from the bottom plate at the first port of the spool through the third chamber, the second middle plate, and the second chamber to the first middle plate, and the first fluid pathway extends through the first tube. The first tube may include a perforated tubing section extending between the first middle plate and the top plate and into the first chamber, and the first fluid pathway may extend through the perforated tubing section of the first tube.

In some embodiments of the pitless adapter according to claim <NUM>, the spool includes a second tube extending from the bottom plate at the second port of the spool through the third chamber to the second middle plate, and the second fluid pathway extends through the second tube.

The second tube may include a perforated tubing section extending between the second middle plate and the first middle plate and into the second chamber, and the second fluid pathway may extend through the perforated tubing section of the second tube.

In some embodiments of the pitless adapter according to claim <NUM>, the spool comprises a third tube having a perforated tubing section extending from the bottom plate at the third port of the spool through the third chamber to the second middle plate, and the third fluid pathway extends through the third tube.

The spool may include at least one pass-through tube extending from an opening in the top plate through an opening in the first middle plate and an opening in the second middle plate to an opening in the bottom plate.

The top plate, the first middle plate, the second middle plate and the bottom plate may each include an annular groove, and the pitless adapter may include an O-ring in each annular groove that forms a seal between the corresponding plate and an interior wall of the casing.

In some embodiments of the pitless adapter according to claim <NUM>, the casing includes a cylindrical wall, and the first port, the second port and the third port of the casing each comprise an opening in the cylindrical wall.

The system according to claim <NUM> includes a pitless adapter and a groundwater heat exchanger. The pitless adapter includes a casing having a first port and a second port, and a spool removably received within an interior cavity of the casing. The spool includes a top plate, a bottom plate, a middle plate between the top and bottom plates, and a first port and a second port in the bottom plate. The casing, the top plate and the middle plate define a first chamber that is open to the first port of the casing and the first port of the spool. The casing, the middle plate and the bottom plate define a second chamber that is open to the second port of the casing and the second port of the spool. A first fluid pathway extends from the first port of the spool through the second chamber and the middle plate to the first chamber. A second fluid pathway extends from the second port of the spool to the second chamber. The groundwater heat exchanger includes a first port and a second port, and is configured to exchange heat between a fluid flow received from the first or second port of the spool with groundwater in which the groundwater heat exchanger is submerged. A first pipe connects the first port of the groundwater heat exchanger to the first port of the spool. A second pipe connects the second port of the groundwater heat exchanger to the second port of the spool.

In some embodiments of the system according to claim <NUM>, the spool comprises a first tube extending from the bottom plate at the first port of the spool to the middle plate, and the first fluid pathway extends through the first tube.

In some embodiments of the system according to claim <NUM>, the spool includes a second tube including a perforated tubing section extending from the bottom plate at the second port of the spool through the second chamber to the middle plate, and the second fluid pathway extends through the perforated tubing section of the second tube.

Embodiments of the present disclosure generally relate to a pitless adapter for groundwater heat exchangers, which are configured for use in a geothermal heat pump system, such as that disclosed in the above-referenced PCT application, and may be configured for use within wells or geothermal boreholes to exchange heat with the earth and/or groundwater. Embodiments of the pitless adapter can, for example, simplify the installation and maintenance of the heat exchangers of the geothermal heat pump system.

Embodiments of the present disclosure are described more fully hereinafter with reference to the accompanying drawings. Elements that are identified using the same or similar reference characters refer to the same or similar elements. The various embodiments of the present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

Specific details are given in the following description to provide a thorough understanding of the embodiments. However, it is understood by those of ordinary skill in the art that the embodiments may be practiced without these specific details. For example, circuits, systems, networks, processes, frames, supports, connectors, motors, processors, and other components may not be shown, or may be shown in block diagram form in order to not obscure the embodiments in unnecessary detail.

<FIG> is a simplified diagram of a geothermal heat pump system <NUM> including one or more groundwater heat exchangers <NUM>, in accordance with embodiments of the present disclosure. The system <NUM> generally includes a ground loop <NUM> that extends into a vertical borehole or well <NUM> (hereinafter "borehole") below the ground surface <NUM>. The borehole <NUM> may penetrate one or more aquifers or aquifer or groundwater zones whereby groundwater <NUM> is present in the borehole <NUM>, such as described in the above-referenced PCT applications. When a borehole is used, it may have a diameter of approximately <NUM>,<NUM> - <NUM> (<NUM>-<NUM> inches), such as <NUM>, <NUM>, <NUM> or <NUM> (<NUM>, <NUM>, <NUM> or <NUM> inches), for example. If a well is used, it may be formed much larger than a typical borehole.

The ground loop <NUM> includes one or more groundwater heat exchangers <NUM>, each of which is positioned within the borehole <NUM> and is submerged within the groundwater <NUM>. A loop fluid flow <NUM> (e.g., water, refrigerant, etc.) that may be driven by a loop pump <NUM> through piping <NUM> of the ground loop <NUM>, such as pipes 116A and 116B. The loop fluid flow <NUM> is driven through each heat exchanger <NUM>, which operates to exchange heat between the loop fluid flow <NUM> and the groundwater <NUM>.

One or more packers <NUM> may be used to secure each heat exchanger <NUM> within the borehole <NUM>, as shown in <FIG>. Such packers may also seal off lower sections of the borehole <NUM> from upper sections. The packers <NUM> may be designed to allow power cables and other wires (e.g., sensor wires) to pass through.

In one embodiment, the piping <NUM> of the ground loop <NUM> forms a closed loop of piping, and does not extract groundwater or carry groundwater to the surface. Separate piping (not shown) may be used to capture and return subsurface groundwater <NUM> to the surface for use (e.g., consumption).

The pipes 116A and 116B that extend below the surface <NUM> may be thermally insulated to reduce heat exchange with their surroundings and isolating the heat exchange with the fluid flow <NUM> to the one or more groundwater heat exchangers <NUM>. Thus, rather than providing heat exchange along nearly the entire length of the borehole <NUM>, embodiments of the system <NUM> provides heat exchange with the groundwater <NUM> at the one or more groundwater heat exchangers <NUM> within the borehole <NUM>.

The system <NUM> may comprise a heat pump <NUM> that includes a main heat exchanger <NUM> that is configured to exchange heat between a fluid flow <NUM> (e.g., water, refrigerant, etc.), which also flows through a heat distribution system <NUM>, and the loop fluid flow <NUM>, as indicated in <FIG>, using any suitable technique. The heat distribution system <NUM> may use the fluid flow <NUM> to provide heating or cooling for a water heater, an HVAC, a chiller, a heat recovery chiller, or another device in accordance with conventional techniques. Alternatively, the system <NUM> may operate without the main heat exchanger <NUM>, and utilize the loop fluid flow <NUM> to directly heat or cool a desired medium.

The heat pump <NUM> may also include conventional heat pump components, such as a compressor <NUM>, an expander <NUM>, and/or other conventional components, as shown in <FIG>, to perform a desired heat pump cycle. While the compressor <NUM> and the expander <NUM> are illustrated as performing a heating cycle based on the direction of the fluid flow <NUM>, it is understood that the direction of the fluid flow <NUM> may be reversed to perform a cooling cycle.

In some embodiments, control and/or balancing valving may be connected to the pipes <NUM> at a location between the heat exchanger <NUM> and the heat pump <NUM> or heat distribution system <NUM>. The valving may be mechanically or electronically controlled, and may be used to match heating and/or cooling load demand from the heat distribution system <NUM> with the supply from the heat exchanger <NUM>, for example. The valving may include a bypass connecting the pipes 116A and 116B that may be used to provide additional control of the loop fluid flow <NUM>.

Each groundwater heat exchanger <NUM> may be formed in accordance with the heat exchangers disclosed in the above-referenced PCT applications. In general, each heat exchanger <NUM> includes a closed fluid pathway that receives the loop fluid flow <NUM> from the system <NUM>, such as through the pipe 116A, and discharges the loop fluid flow <NUM> to the pipe 116B to return the loop fluid flow <NUM> back to the system <NUM>, such as back to the heat pump <NUM>. As the loop fluid flow <NUM> travels through the fluid pathway of each groundwater heat exchanger <NUM>, heat is exchanged between the loop fluid flow <NUM> and the groundwater <NUM>, in which the groundwater heat exchanger <NUM> is submerged.

Embodiments of the present disclosure are directed to a spool-type pitless adapter <NUM> for handling the exchange of the loop fluid flows <NUM> between the heat pump <NUM> and the one or more groundwater heat exchangers <NUM>. A simplified illustration of an example of a pitless adapter <NUM> formed in accordance with embodiments of the present disclosure is provided in <FIG>.

The pitless adapter <NUM> may be positioned at or near the top of the borehole <NUM>, or within the borehole <NUM>. The pitless adapter <NUM> generally includes a housing or casing <NUM> and a spool <NUM>. The casing <NUM> may be secured to a wall of the borehole <NUM> or to a riser pipe that extends to the surface to prevent water from entering the top side of the adapter <NUM>. The casing <NUM> includes an interior cavity <NUM>, in which the spool <NUM> is received.

The casing <NUM> may include two or more ports <NUM>, such as ports 138A and 138B, that are configured to receive and discharge the loop fluid flow <NUM>. In some embodiments, the casing <NUM> includes additional ports, such as port 138C for receiving a separate fluid flow <NUM>, such as a flow of the groundwater <NUM>, which may be used as potable or process water, or a flow of a combination of the fluid flow <NUM> and the groundwater <NUM>. The ports <NUM> may be located above the ground surface <NUM> (<FIG>), the ports <NUM> may be within the borehole <NUM> (e.g., <NUM>-<NUM> (<NUM>-<NUM> feet) below the surface <NUM>), or some of the ports <NUM> may be located above the ground surface <NUM>, while other ports <NUM> are located within the borehole <NUM> and below the ground surface <NUM>.

The casing <NUM> and the spool <NUM> may be formed of any suitable material. In some embodiments, the casing <NUM> and/or the spool <NUM> are constructed of materials that are not chemically reactive to common fluids such as potable water that may pass through them, such as PVC, mild steel, stainless steel, and brass.

The spool <NUM> may have multiple ports <NUM>, such as ports 140A and 140B, through which the flows <NUM> are discharged to the heat exchanger <NUM> or received from the heat exchanger <NUM>. Additional ports <NUM> may be used to connect the flows <NUM> to other heat exchangers, or to receive a flow <NUM> of the groundwater <NUM>, as indicated by port 140C.

In some embodiments, the spool <NUM> is removably attached to the casing <NUM>. Due to the connections to the one or more heat exchangers <NUM>, such as through the pipes <NUM>, the removal of the spool may also facilitate the removal of the heat exchanger <NUM> and other components, such as pumps <NUM> for circulating the groundwater <NUM>, sensors <NUM> for detecting a temperature of the groundwater <NUM>, and/or other components, for example.

An example of a two-port pitless adapter <NUM> will be described with reference to <FIG>. <FIG> is a simplified cross-sectional view of a two-port pitless adapter <NUM> installed in a borehole <NUM>, in accordance with embodiments of the present disclosure. <FIG> is an isometric view of an example of the pitless adapter <NUM>, in accordance with embodiments of the present disclosure. <FIG> is a cross-sectional view of the pitless adapter <NUM> in accordance with embodiments of the present disclosure. <FIG> is an isometric view of the casing <NUM> of the pitless adapter <NUM>, in accordance with embodiments of the present disclosure. <FIG> and <FIG> are isometric views of an example of a spool <NUM> of the pitless adapter <NUM>, in accordance with embodiments of the present disclosure. <FIG> is a bottom isometric view of an example of a top plate 160A of the spool <NUM>, <FIG> is a top isometric view of a middle plate 160B of the spool <NUM>, and <FIG> is a top isometric view of a bottom plate 160C of the spool <NUM>, in accordance with embodiments of the present disclosure.

In the provided example, the casing <NUM> of the pitless adapter <NUM> includes two ports 138A and 138B for receiving and discharging the loop fluid flows <NUM>, and the spool <NUM> includes two ports 140A and 140B for coupling the fluid flows <NUM> to one or more heat exchangers <NUM>. In some embodiments, the spool <NUM> includes a distinct chamber <NUM> for each of the ports <NUM>.

In the example pitless adapter <NUM> of <FIG>, the spool <NUM> includes a chamber 150A corresponding to the port 138A, and a chamber 150B corresponding the port 138B. Each of the chambers <NUM> of the spool <NUM> may be defined by plates <NUM> of the spool <NUM> and the wall <NUM> (<FIG>) of the casing <NUM>, which may take the form of a cylindrical wall. For example, the chamber 150A is defined by the wall <NUM> of the casing <NUM>, a top plate 160A of the spool <NUM>, and a middle plate 160B of the spool <NUM>. Similarly, the chamber 150B is defined by the wall <NUM> of the casing <NUM>, the middle plate 160B and a bottom plate 160C of the spool <NUM>.

Each of the chambers <NUM> may be sealed using any suitable technique. For example, O-rings <NUM> (e.g., within annular grooves <NUM> of the plates <NUM> (<FIG>)), gaskets, or other suitable sealing components may be used to form seals between the plates <NUM> and the casing <NUM>. In one embodiment, a dielectric seal is formed between the components of the spool <NUM>, such as the plates <NUM>, and the casing <NUM>, such as when the plates <NUM> are formed of stainless steel and the casing <NUM> is formed of mild steel to prevent corrosion.

In some embodiments, the spool <NUM> includes fluid pathways <NUM> that fluidically connect the chambers <NUM> to their corresponding ports <NUM>. The fluid pathways <NUM> may be formed using tubing <NUM> that extends through one or more of the plates <NUM> of the spool <NUM>. For example, a tube 166A may form a fluid pathway 164A (<FIG>, <FIG> and <FIG>) that extends through an opening <NUM> (<FIG>) in the plate 160B and an opening <NUM> in the plate 160C and connects the chamber 150A to the port 140A (<FIG>), and a tube 166B may form a fluid pathway 164B (<FIG>, <FIG> and <FIG>) that extends through an opening <NUM> (<FIG>) in the plate 160C and connects the chamber 150B to the port 140B, as shown in <FIG>. It is understood that the tubes 166A and 166B may be formed by tubing sections that connect to corresponding openings <NUM> (<FIG> and <FIG>) in the plates 160B and/or 160C, such as using appropriate connectors or fittings. A suitable seal may be formed between the tubes <NUM> forming the fluid pathways <NUM> and the corresponding plates <NUM> to seal the fluid pathways <NUM>.

One or more of the tubes <NUM> may be used to connect the plates <NUM> of the spool <NUM> together, such that the spool <NUM> may be handled as a single unit. For example, the tube 166A and/or 166B (<FIG>, <FIG> and <FIG>) or a corresponding section thereof, may be attached to the plate 160A, such as at an opening or a closed socket <NUM> (<FIG>). The tube 166A and/or 166B may also be attached to the plates 160B and 160C. This improves the rigidity of the structure, which is useful when inserting the spool <NUM> into the interior cavity <NUM> of the casing <NUM>.

In some embodiments, the fluid pathways <NUM> include a port <NUM> within the corresponding chamber <NUM>, through which the fluid flow <NUM> travels. For example, the fluid pathway 164A may include a port 168A within the chamber 150A, and the fluid pathway 166B may include a port 168B within the chamber 150B, as shown in <FIG>. Each of the ports <NUM> operates to either receive the fluid flow <NUM> from within the chamber <NUM>, or discharge the fluid flow <NUM> within the chamber <NUM>. In one embodiment, the ports <NUM> each comprise a perforated tubing section <NUM> having perforations or openings <NUM>, through which the fluid flow <NUM> may travel.

Thus, in operation, a fluid flow 112A may be received at the port 138A, through which it is introduced to the chamber 150A, as shown in <FIG>. That fluid flow 112A then travels through the port 168A of the fluid pathway 164A, from which it travels to the port 140A where it is coupled to the pipe 116A, where it is delivered to one or more heat exchangers <NUM>. As mentioned above, each heat exchanger <NUM> includes a fluid pathway that circulates the received loop fluid flow 112A. Heat is exchanged between the circulating loop fluid flow 112A and the groundwater <NUM>, in which the groundwater heat exchanger <NUM> is submerged.

After this heat exchange, the loop fluid flow 112A is returned as loop fluid flow 112B from the one or more heat exchangers <NUM> through the pipe 116B to the port 140B. The loop fluid flow 112B then travels through the fluid pathway 164B and into the chamber 150B through the port 168B, as indicated in <FIG>. The loop fluid flow 112B may then be discharged through the port 138B and returned to the main heat exchanger <NUM> (<FIG>).

In some embodiments, the ports 140A and 140B include suitable connectors or fittings for coupling the pipes 116A and 116B to the ports 140A and 140B, such as a weldolet, a threadolet, or another suitable connector.

In one embodiment, the ports 140A and 140B are configured to couple to the same diameter piping <NUM>. This generally limits the diameter of the pipes 116A and 116B to approximately <NUM>,<NUM> (<NUM> inches) for a <NUM> (<NUM>-inch) bore <NUM>, or <NUM> (<NUM> inches) for an <NUM> (<NUM>-inch) bore <NUM>, due to the size of the joints at the ports 140A and 140B, for example.

Alternatively, the ports 140A and 140B may be configured to couple to different diameter piping <NUM>, such that pipe 116A has a different diameter than the pipe 116B to increase or maximize the total combined cross-sectional area of the pipes 116A and 116B relative to when the pipes 116A and 116B have the same diameter. For example, when the borehole <NUM> has a <NUM> (<NUM>-inch) diameter, one of the ports 140A and 140B may be configured to accommodate a <NUM> (<NUM>-inch) pipe <NUM>, while the other is configured to accommodate a <NUM>,<NUM> (<NUM>-inch) pipe <NUM>. Similarly, when the borehole <NUM> has an <NUM> (<NUM>-inch) diameter, one of the ports 140A and 140B may be configured to accommodate a <NUM>,<NUM> (<NUM>-inch) pipe <NUM>, while the other is configured to accommodate a <NUM> (<NUM>-inch) pipe <NUM>, for example. The resulting increase in the total cross-sectional area of the pipes <NUM> may result in a significant pressure drop reduction over the corresponding configuration using piping <NUM> having the same diameter. Additionally, the use of differently sized ports 140A and 140B limits the attachment of the pipes 116A and 116B to a single configuration, thus ensuring that the pipes <NUM> are connected to the correct ports.

In some embodiments, the top plate 160A may include a connector <NUM>, such as, for example, a female pipe thread (FPT) coupling at its center, to which a pipe may be connected when it is desired to remove the spool <NUM> from the casing <NUM>, such as when the pitless adapter <NUM> is positioned beneath the surface <NUM> within the borehole <NUM>. Thus, a pipe may be extended below the surface <NUM> into the borehole <NUM> and screwed into the connector <NUM>, and used to remove the spool <NUM> from the casing <NUM> along with the attached heat exchangers <NUM> and other components (e.g., pump <NUM>, sensors <NUM>, etc.).

In some embodiments, one or more cables <NUM> connect the spool <NUM> to the heat exchanger <NUM>, as shown in <FIG>. The cables <NUM> operate to support and secure the position of the heat exchanger <NUM> within the borehole <NUM>, and reduce stress on the pipes <NUM> during use of the heat exchanger <NUM> and during the removal of the heat exchanger <NUM> with the spool <NUM>. The cables <NUM> may be attached to the spool <NUM> using any suitable technique, such as eye loops <NUM> attached to the bottom plate 160C, for example, as shown in <FIG>. A similar technique may be used to attach the cables <NUM> to the heat exchanger <NUM>, as indicated in <FIG>.

In some embodiments, the spool <NUM> includes one or more pass-throughs <NUM>, through which power cables, wires (e.g., sensor wires) and other components may be fed from components above the surface <NUM> (e.g., power supplies, a controller <NUM>, etc.) to pumps <NUM>, sensors <NUM>, and/or other components located within the borehole <NUM>, for example, as indicated in <FIG>. Each pass-through <NUM> may be formed by tubing <NUM> that extends through the plates <NUM>, such as through openings <NUM> (<FIG>) in the plates <NUM>, or tubing sections that connect to the plates <NUM>. The tubing <NUM> may be attached to each of the plates <NUM> to connect the plates <NUM> together and fix the assembly of the spool <NUM>.

In one example configuration of the pitless adapter <NUM>, the top plate 160A may be <NUM> (<NUM> inches) thick. The top <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM>) inch, and the next <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches), thereby creating a shoulder that abuts the top of the casing <NUM> when the spool <NUM> is fully installed in the cavity <NUM> (<FIG> and <FIG>). The next <NUM> (<NUM> inch, groove <NUM>) may have an outer diameter of <NUM> (<NUM> inches), and the bottom <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches). Through holes <NUM> may be configured for <NUM> (<NUM>-inch) schedule <NUM> pass-through pipes (~<NUM> (<NUM> inches)) <NUM> that are <NUM> (<NUM> inches) long, and the holes <NUM> may be opposite each other and <NUM> (<NUM> inches) from center. The sockets or openings <NUM> may each be <NUM> (<NUM> inch) deep placement pockets (on the bottom surface) for <NUM> (<NUM>-inch) schedule <NUM> pipes (~<NUM> or ~<NUM> inches) <NUM> and may be opposite each other and <NUM> (<NUM> inches) from center. The connector <NUM> on the top plate 160A may have a <NUM> (<NUM>-inch) FPT coupling centered on it (not for fluid flow).

One example of the middle plate 160B is <NUM> (<NUM> inches) thick. The top <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches), the next <NUM> (<NUM> inch, groove <NUM>) may have an outer diameter of <NUM> (<NUM> inches), and the bottom <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches). The through holes <NUM> may each be configured for <NUM> (<NUM>-inch) schedule <NUM> pipe (~<NUM>,<NUM> (<NUM> inches)) <NUM>, and may be opposite each other and <NUM> (<NUM> inches) from center. The through holes <NUM> may each be configured for a <NUM> (<NUM>-inch) schedule <NUM> pipe (~<NUM> (<NUM> inches)) <NUM>, and may be opposite each other and <NUM> (<NUM> inches) from center.

One example of the bottom plate 160C is <NUM> (<NUM> inches) thick. The top <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches), the next <NUM> (<NUM> inch, groove <NUM>) may have an outer diameter of <NUM> (<NUM> inches), and the bottom <NUM> (<NUM> inch) may have an outer diameter of <NUM> (<NUM> inches). The through holes <NUM> may be configured for <NUM> (<NUM>-inch) schedule <NUM> pipe (~<NUM> or ~<NUM> inches) <NUM> and may be opposite each other and <NUM> (<NUM> inch) from center. The through holes <NUM> may be configured to match the outer diameter of <NUM> (<NUM>-inch) schedule <NUM> pipes (~<NUM>,<NUM> or <NUM> inches) <NUM> and may be opposite each other and (<NUM> or <NUM> inches) from center. The top surface may include <NUM> (<NUM> inch) deep placement pockets that are each configured for a <NUM> (<NUM>-inch) schedule <NUM> pipe (~<NUM> or <NUM> inches) <NUM> and may be opposite each other and <NUM> (<NUM> inches) from center. The bottom surface may include <NUM> (<NUM> inch) deep placement pockets with <NUM> (<NUM>-inch) FPT configured for the <NUM> (<NUM>-inch) schedule <NUM> pipes <NUM>, and the pockets may be opposite each other and <NUM> (<NUM>) inches from center.

The wall <NUM> of the casing <NUM> may comprise an <NUM> (<NUM>-inch) schedule <NUM> pipe that is <NUM> (<NUM> inches) long. The ports 138A and 138B may be <NUM> (<NUM> inch) through holes for <NUM> (<NUM>-inch) FPT coupling, and may be <NUM> (<NUM> inches) and <NUM> (<NUM> inches) down from the top surface of the casing <NUM>, and <NUM> degrees from each other circumferentially. Each port <NUM> may include a <NUM>,<NUM> (<NUM>-inch) FPT coupling that may be cut to have a smooth joint with the <NUM> (<NUM>-inch) pipe. The casing <NUM> may have a ring welded around its outside diameter at the top surface, which may be welded to a riser pipe with an inside diameter greater than the outside diameter of the casing.

As indicated above, the tubes <NUM> may each be a <NUM> (<NUM>-inch) schedule <NUM> pipe, that is approximately <NUM> (<NUM> inches) long. The perforations or openings <NUM> of the tubing section <NUM> may run from <NUM> (<NUM> inch) to <NUM> (<NUM> inches) and <NUM> (<NUM> inches) to <NUM> (<NUM> inches) from the top surface for tube 166A, and may run from <NUM> (<NUM> inch) to <NUM> (<NUM> inches) and <NUM> (<NUM> inches) to <NUM> (<NUM> inches) from the bottom surface for tube 166B. The openings <NUM> may comprise <NUM> cut-outs total, <NUM> per row and, circumferentially, <NUM> degree webs and <NUM> degree cut-outs, for example.

This configuration results in chambers <NUM> where the top chamber is about <NUM> (<NUM> inches) in height and the bottom chamber is about <NUM>,<NUM> (<NUM> inches) in height measured along the central axis of the casing <NUM>.

Clearance between each <NUM> (<NUM> inch) plate and the <NUM> (<NUM> inch) inner diameter of the <NUM> (<NUM> inch) schedule <NUM> pipe forming the wall <NUM> of the casing <NUM> is intentional. This gap allows <NUM> (<NUM> inch) O-rings <NUM> to be positioned in each groove <NUM> to seal the chambers <NUM> against the wall <NUM> of the casing <NUM>, as shown in <FIG>.

<FIG> illustrate an example of a three-port pitless adapter <NUM>, in accordance with embodiments of the present disclosure. <FIG> is an isometric view of the pitless adapter <NUM>, <FIG> is an isometric cross-sectional view of the pitless adapter <NUM>, and <FIG> and <FIG> are isometric views of a spool of the pitless adapter <NUM>, in accordance with embodiments of the present disclosure. Elements that are identified using the same or similar reference characters as those discussed above, generally refer to the same or similar elements.

The pitless adapter <NUM> comprises a casing <NUM> and a spool <NUM>, which are similar to the casing <NUM> and the spool <NUM> of the pitless adapter <NUM>. The casing <NUM> includes an additional port 138C over the ports 138A and 138B of the two-port pitless adapter <NUM>. Additionally, the spool <NUM> includes a middle plate 160D positioned between the middle plate 160B and the bottom plate 160C of the two-port pitless adapter <NUM> example. As a result, in addition to the chambers 150A and 150B, the spool <NUM> includes a chamber 150C that is open to the port 138C. The chamber 150B is formed between the casing <NUM> and the plates 160B and 160D, and the chamber 150C is formed between the casing <NUM> and the plates 160C and 160D, as shown in <FIG>. The spool <NUM> also includes a port 140C along with the ports 140A and 140B in the bottom plate 160C. The additional ports 138C, 140C and the additional chamber 150C allow the pitless adapter <NUM> to accommodate a third fluid flow into or out of the port 138C. In some embodiments, this fluid flow may be a flow of the groundwater <NUM> to the surface <NUM>, for example, which may be used as potable water, process water, irrigation water, or another purpose.

In addition to the fluid pathways 164A and 164B connected to chambers 150A and 150B, the pitless adapter <NUM> includes a fluid pathway 164C that extends through the plate 160C, and may be coupled to a port 140C, which may in turn be connected to a pipe 116C (<FIG>) that extends into the borehole <NUM>. A fluid flow <NUM> (or <NUM> in <FIG>) is directed between the port 138C and the port 140C, such as in the direction indicated by the arrows or the opposite direction. The fluid pathway 164C may be formed by tubing 166C and have similar features as the tubing 166A and 166B described above. The plates <NUM> of the spool <NUM> may be adapted to accommodate the tubing 166C in a similar manner as described above. The fluid flow <NUM> may be received by the port 140C, travel through the port 168C, into the chamber 150C and out through the port 138C, or travel in the opposite direction along this path.

The length of the casing <NUM> is extended relative to the casing <NUM> to accommodate the additional port 138C and chamber 150C and the plate 160D. The fluid pathways <NUM> and the pass-throughs <NUM> may be extended accordingly. Otherwise, similar dimensions apply for the components forming the pitless adapter <NUM>, as those discussed above for the pitless adapter <NUM>.

Claim 1:
A pitless adapter (<NUM>) for use with a groundwater heat exchanger (<NUM>) comprising:
a casing (<NUM>) comprising a first port (138A) a second port (138B) and a third port (138C); and
a spool (<NUM>) removably received within an interior cavity of the casing (<NUM>), the spool (<NUM>) including:
a top plate (160A);
a bottom plate
a first middle plate (160B) between the top and bottom plates;
a second middle plate (160D) between the first middle plate (160B) and the bottom plate (160C);
a first port (140A), a second port (140B), and a third port (140C) in the bottom plate (160C),
wherein:
the casing (<NUM>), the top plate (160A) and the first middle plate (160B) define a first chambe (150A)
that is open to the first port (138A) of the casing (<NUM>) and the first port (140A) of the spool (<NUM>);
the casing (<NUM>), the first middle plate (160B) and the second middle plate (160D) define a second chamber (150B) that is open to the second port (138B) of the casing (<NUM>) and
the second port (140B) of the spool (<NUM>); the casing (<NUM>), the second middle plate (160D) and the bottom plate (160C) define a third chamber (150C) that is open to the third port (138C) of the casing (<NUM>) and the third port (140C) of the spool (<NUM>);
a first fluid pathway (164A) extends from the first port (138A) of the spool (<NUM>) through the third chamber (150C), the second middle plate (160D), the second chamber (150B), and the first middle plate (160B) to the first chamber (150A);
a second fluid pathway (164B) extends from the second port (140B) of the spool (<NUM>) through the third chamber (150C), and the second middle plate (150D) to the second chamber (150B); and
a third fluid pathway (164C) extends from the third port (140C) of the spool (<NUM>) to the third chamber (150C).