The following application is filed on the same day as the following co-pending applications: “METHOD AND SYSTEM FOR HORIZONTAL COIL CONDENSATE DISPOSAL” by inventors Arturo Rios, Floyd J. Frenia, Jason Michael Thomas, Michael V. Hubbard, and Thomas K. Rembold (attorney docket number U75.12-003); “CASING ASSEMBLY SUITABLE FOR USE IN A HEAT EXCHANGE ASSEMBLY” by inventors Floyd J. Frenia, Arturo Rios, Thomas K. Rembold, Michael V. Hubbard, Jason Michael Thomas, and Stephen R. Carlisle (attorney docket number U75.12-004); “CONDENSATE PAN INSERT” by inventors Jason Michael Thomas, Floyd J. Frenia, Thomas K. Rembold, Arturo Rios, Michael V. Hubbard, and Dale R. Bennett (attorney docket number U75.12-005); “METHOD AND SYSTEM FOR VERTICAL COIL CONDENSATE DISPOSAL” by inventors Thomas K. Rembold, Arturo Rios, Jason Michael Thomas, and Michael V. Hubbard (attorney docket number U75.12-006); “LOW-SWEAT CONDENSATE PAN” by inventors Arturo Rios, Floyd J. Frenia, Thomas K. Rembold, Michael V. Hubbard, and Jason Michael Thomas (attorney docket number U75.12-008); “CONDENSATE PAN INTERNAL CORNER DESIGN” by inventor Arturo Rios (attorney docket number U75.12-009); “VERTICAL CONDENSATE PAN WITH NON-MODIFYING SLOPE ATTACHMENT TO HORIZONTAL PAN FOR MULTI-POISE FURNACE COILS” by inventor Arturo Rios (attorney docket number U75.12-010); “CONDENSATE SHIELD WITH FASTENER-FREE ATTACHMENT FOR MULTI-POISE FURNACE COILS” by inventor Arturo Rios (attorney docket number U75.12-011); and “SPLASH GUARD WITH FASTENER-FREE ATTACHMENT FOR MULTI-POISE FURNACE COILS” by inventor Arturo Rios (attorney docket number U75.12-012), which are incorporated herein by reference.
The present invention relates to a casing assembly. More particularly, the present invention relates to a casing assembly suitable for use in a heat exchange assembly, such as an evaporator assembly.
In a conventional refrigerant cycle, a compressor compresses a refrigerant and delivers the compressed refrigerant to a downstream condenser. From the condenser, the refrigerant passes through an expansion device, and subsequently, to an evaporator. The refrigerant from the evaporator is returned to the compressor. In a split system heating and/or cooling system, the condenser may be known as an outdoor heat exchanger and the evaporator as an indoor heat exchanger, when the system operates in a cooling mode. In a heating mode, their functions are reversed.
In the split system, the evaporator is typically a part of an evaporator assembly coupled with a furnace. However, some cooling systems are capable of operating independent of a furnace. A typical evaporator assembly includes an evaporator coil (e.g., a coil shaped like an “A”, which is referred to as an “A-frame coil”) and a condensate pan disposed within a casing. An A-frame coil is typically referred to as a “multi-poise” coil because it may be oriented either horizontally or vertically in the evaporator assembly.
During a cooling mode operation, a furnace blower circulates air into the casing of the evaporator coil assembly, where the air cools as it passes over the evaporator coil. The blower then circulates the air to a space to be cooled. Depending on the particular application, an evaporator assembly including a vertically oriented A-frame coil may be an up flow or a down flow arrangement. In an up flow arrangement, air is circulated upwards, from beneath the evaporator coil assembly, whereas in a down flow arrangement, air is circulated downward, from above the evaporator coil assembly.
Refrigerant is enclosed in piping that is used to form the evaporator coil. If the temperature of the evaporator coil surface is lower than the dew point of air passing over it, the evaporator coil removes moisture from the air. Specifically, as air passes over the evaporator coil, water vapor condenses on the evaporator coil. The condensate pan of the evaporator assembly collects the condensed water as it drips off of the evaporator coil. The collected condensation then typically drains out of the condensate pan through a drain hole in the condensate pan.
The present invention is a casing assembly suitable for use in a heat exchange assembly. The casing assembly includes a body, and first and second covers that are attached to the body. A first sealing mechanism positioned between the first and second covers provides a substantially airtight seam between the first and second covers. In one embodiment, the first sealing mechanism is a first gasket positioned along a first portion of the first cover, where the first gasket interfaces with the second cover to form the substantially airtight seam. The first cover of the casing assembly defines an opening configured to receive a drain connection of a condensate pan. A second sealing mechanism positioned between the first cover and the drain connection of the condensate pan provides a substantially airtight interface therebetween. In one embodiment, the second sealing mechanism includes a lip surrounding at least a part of an outer perimeter of the opening in the first cover, where the lip is configured to engage with a second gasket surrounding the drain connection.
Coil 6, condensate pan 14, and condensate pan 16 are disposed within casing 4, which is preferably a substantially airtight space for receiving and cooling air. That is, casing 4 is preferably impermeable to air except for openings 4A and 4B (shown in
Coil 6 is a multi-poise A-frame coil, and may be oriented either horizontally or vertically. The vertical orientation is shown in
Coil 6 includes first slab 6A and second slab 6B connected by air seal 28. A gasket may be positioned between air seal 28 and first and second slabs 6A and 6B, respectively, to provide an interface between air seal and slabs 6A and 6B that is substantially impermeable to water. First and second delta plates 12 and 14, respectively, are positioned between first and second slabs 6A and 6B, respectively. First slab 6A includes multiple turns of piping 30A with a series of thin, parallel fins 32A mounted on piping 30A. Similarly, second slab 6B includes multiple turns of piping 30B with a similar series of thin, parallel fins mounted on piping 30B. Tube sheet 29A is positioned at an edge of slab 6A, and tube sheet 29B is positioned at an edge of slab 6B. Delta plates 10 and 12, and air seal 28 may be attached to tube sheets 29A and 29B.
In the embodiment shown in
As discussed in the Background section, if the temperature of coil 6 surface is lower than the dew point of the air moving across coil 6, water vapor condenses on coil 6. If coil 6 is horizontally oriented, condensation from coil 6 drips into condensate pan 14, and drains out of condensate pan 14 through drain holes 15, which are typically located at the bottom of condensate pan 14. If coil 6 is vertically oriented, condensate pan 16 collects the condensed water from coil 6, and drains the condensation through drain holes 17, which are typically located at the bottom of condensate pan 16.
Because evaporator assembly 2 includes horizontal condensate pan 14 and vertical condensate pan 16, evaporator assembly 2 is configured for applications involving a horizontal or vertical orientation of coil 6. In an alternate embodiment, evaporator assembly 2 is modified to be applicable to only a vertical orientation of coil 6, in which case horizontal condensate pan 14 and brace 8 are absent from evaporator assembly 2. In another alternate embodiment, evaporator assembly 2 excludes vertical condensate pan 16 such that evaporator assembly 2 is only applicable to horizontal orientations of coil 6.
Horizontal and vertical condensate pans 14 and 16 are typically formed of a plastic, such as polyester, but may also be formed of any material that may be casted, such as metal (e.g., aluminum). Horizontal condensate pan 14 slides into casing 4 and is secured in position by pan supports 46. Tabs 46A of pan supports 46 define a space for condensate pan 14 to slide into. When coil 6 is in a horizontal orientation (and casing 4 is rotated about 90° in a counterclockwise direction), coil 6 is positioned above horizontal condensate pan 14 so that condensation flows from coil 6 into horizontal condensate pan 14. Air splitter 44 and splash guards 45A and 45B also help guide condensation from coil 6 into horizontal condensate pan 14.
Condensation that accumulates in horizontal condensate pan 14 eventually drains out of horizontal condensate pan 14 through drain holes 15. Gasket 52A is positioned around drain holes 15 prior to positioning first cover 18 over drain holes 15 in order to help provide a substantially airtight seal between drain holes 15 and first cover 18. First cover 18 includes opening 53A, which corresponds to and is configured to fit over drain holes 15 and gasket 52A. The substantially airtight seal helps prevent air from escaping from casing 4, and thereby increases the efficiency of evaporator assembly 2. Caps 56A may be positioned over one or more drain holes 15, such as when evaporator assembly 2 is used in an application in which coil 6 is vertically oriented.
Vertical condensate pan 16 slides into casing 4 and is supported, at least in part, by flange 48, which is formed by protruding sheet metal on three-sides of casing 4 and top surface 39A of front deck 39. Specifically, bottom surface 16A of condensate pan 16 rests on flange 48 and top surface 39A of front deck 39. Condensate pan 16 includes outer perimeter 49, insert 50, drain holes 17 (which are sealed by gasket 52B) and plurality of ribs 54.
One or more channels are positioned about outer perimeter 49 of vertical condensate pan 16 for receiving condensation from coil 6. In the vertical orientation of coil 6 illustrated in
Evaporator assembly 2 includes features, such as ribs 54 and shield 58, that are configured to help direct condensation into the one or more channels along outer perimeter 49 of vertical condensate pan 16 (when coil 6 is vertically oriented). Shield 58 is attached to tube sheet 29A and is configured to both guide condensation into a channel along outer perimeter 49 of condensate pan 16 and help protect coil 6 from condensation blow-off, which occurs when condensation that is collected in condensate pan 16 is blown into the air stream moving through evaporator assembly 2. A similar shield is attached to tube sheet 29B.
Condensation that accumulates in vertical condensate pan 16 eventually drains out of vertical condensate pan 16 through drain holes 17. Gasket 52B is positioned around drain holes 17 prior to positioning first cover 18 over drain holes 17 in order to help provide a substantially airtight seal between drain holes 17 and first cover 18. First cover 18 includes opening 53B, which corresponds to and is configured to fit over drain holes 17 and gasket 52B. The airtight seal helps prevent air from escaping from casing 4, and thereby increases the efficiency of evaporator assembly 2. Cap 56B may be positioned over one or more drain holes 17.
Piping system 62 fluidically connects piping 30A of first slab 6A and piping 30B of second slab 6B. Refrigerant flows through piping 30A and 30B, and is recirculated from and to a compressor through inlet and outlet tubes 20 and 22, respectively. Specifically, refrigerant is introduced into piping 30A and 30B through inlet 20 and exits piping 30A and 30B through outlet 22. As known in the art, refrigerant inlet 20 includes rubber plug 64, and refrigerant outlet 22 includes strainer 66 and rubber plug 68. Inlet 20 protrudes through opening 70 in first cover 18 and outlet 22 protrudes through opening 72 in first cover 18. By protruding through first cover 18 and out of casing 4, inlet 20 and outlet 22 may be connected to refrigerant lines that are fed from and to the compressor, respectively. Gasket 74 is positioned between inlet 20 in order to provide a substantially airtight seal around opening 70. Similarly, gasket 76 is positioned around outlet 22.
Access cover 38 is attached to casing 4, first cover 18, front deck 39, and upper angle 40 with a plurality of screws 82. More specifically, first and second portions 38A and 38B of access cover 38 are attached to first cover 18 with screws 82, and third portion 38C of access cover 38 is attached to front deck 39 with screws 82. Fourth and sixth portion 38D and 38F, respectively, of access cover 38 is attached to casing 4 using screws 82, and fifth portion 38E of access cover 38 contacts upper angle 40. In alternate embodiments, other means of removably attaching access cover 38 to casing 4, first cover 18, front deck 39, and upper angle 40 are used. Access cover 38 is preferably removably attached in order to provide access to coil 6, condensate pan 16, and other components inside casing 4 for maintenance purposes. One or more labels 84, such as warning labels, may be placed on first cover 18 and/or access cover 38.
First and second portions 18A and 18B of first cover 18 abut first and second portions 38A and 38B of access cover 38, respectively, thereby defining seam 81 (shown in
In the embodiment shown in
First cover includes lips 103A and 103B. Lip 103B, which extends around an outer perimeter of opening 53B in first cover 18, engages with gasket 52B (positioned between drain holes 17 and opening 53B) to provide a substantially airtight seal between opening 53B in first cover 18 and drain holes 17 in vertical condensate pan 16. Gasket 52B is positioned between lip 103B and drain holes 17 when first cover 18 is attached to casing 4. As previously discussed, a similar gasket 52A (shown in
Openings 70 and 72 for refrigerant inlet 20 and outlet 22 (shown in
Access cover 38 includes extensions 106 and 108, which are configured to wrap around casing 4 and securely fit access cover 38 to casing 4. First cover 18 also includes extension 110, which is configured to wrap around casing 4. As the assembly lines in
Gasket 100 is aligned to attach to a front surface of flange 101 of first cover 18. Flange 101 extends from first and second portions 18A and 18B of first cover 18 and protrudes slightly therefrom in an x-axis direction (where orthogonal x-y-z coordinates are shown in
While the present invention has been described with reference to evaporator unit 2, a casing assembly including a sealing mechanism positioned between a first cover and an access cover in accordance with the present invention is suitable for use with any heat exchange assembly.
The terminology used herein is for the purpose of description, not limitation. Specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as bases for teaching one skilled in the art to variously employ the present invention. Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.