US3602006A

US3602006A - Room air conditioner

Info

Publication number: US3602006A
Application number: US857914A
Authority: US
Inventors: Frederick S Metcalfe; Edward M Wuesthoff
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1969-09-15
Filing date: 1969-09-15
Publication date: 1971-08-31
Anticipated expiration: 1988-08-31
Also published as: JPS4724222B1

Abstract

A room air conditioner of the character having a main section depending along an outside building wall below the building opening and with a duct section connected to the building opening, the main section including an upper room air section and a lower outside air section, the room air section including a pair of centrifugal fans disposed with their axes extending horizontally and located in the lower part of the room air section with the centrifugal fan housings oriented to provide an upblast disposition, the fan discharge being conveyed upwardly and forwardly through a pair of ducts having expanding end sections at the upstream face of an evaporator extending across substantially the entire width of the room air section and disposed in registry with the upper air passage of the duct section.

Description

United States Patent [72] inventors Frederick S. Metcalfe Columbus; Edward M. Wuesthott, Worthington, both of, Ohio [21] Appl. No. 857,914 [22] Filed Sept. 15, 11969 [45] Patented Aug. 31, 19711 [73] Aesignee Westinghouse Electric Corporation Pittsburgh, Pa.

[ 54] ROOM AIR CONDITIONER 8 Claims, 8 Drawing Figs. [52] [1.8. Ci 62/262, 62/263 [5 i 1 Int. Cl JFZSd 23/12 [50] Field oi Search. 62/262, 263 [56] References Cited UNITED STATES PATENTS 3,018,642 1/1962 Lathrop 62/262 3,045,448 7/1962 Lauer. 62/263 3,404,539 10/1968 Laing 3,491,549 1/1970 Oglesby Primary Examiner-William J. Wye AttorneysF. H. Henson and E. C. Arenz ABSTRACT: A room air conditioner of the character having a main section depending along an outside building wall below the building opening and with a duct section connected to the building opening, the main section including an upper room air section and a lower outside air section, the room air section tending horizontally and located in the lower part of the room air section with the centrifugal fan housings oriented to provide an upblast disposition, the fan discharge being conveyed upwardly and forwardly through a pair of ducts having expanding end sections at the upstream face of an evaporator extending across substantially the entire width of the room air section and disposed in registry with the upper air passage of the duct section.

PATENTEU M831 l9?! 3,602.006

SHEET 1 OF 4 VENTORS Fre S. Metcolfe 0nd Ed d M. Wuesthoff ATTORNEY PATENTED AUGBI I97! SHEET 2 OF 4 FIGS.

PATENTEU AUGBI l97l SHEET 3 [IF 4 FIG] PATENTEU AUEBI Ian SHEET 4 [IF 4 ROOM AIR CONDITIONER CROSS REFERENCE TO RELATED APPLICATIONS Related US. patent applications are Ulich, Ser. Nos. 781,516, now US. Pat. No. 3,548,611 and 781,517, now U.S. Patent No. 3,552,139 and Oberdier, Ser. No. 781,518, now US. Patent No. 3,543,533.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains to the art of room air conditioners of the character which are mounted outside a building wall to depend below an opening therein and which have aduct section connecting the main section to the building opening.

2. Description of the Prior Art US. Patents of which we are aware and which disclose room air conditioners mounted substantially entirely outside of the room being conditioned and which includea casing depending along the exterior of the building wall below an opening in the wall are: 3,313,122; D-l79,726; 2,753,699; 2,737,788; 2,667,765; 2,660,867; and 2,660,866, for example.

Outside mounted room air conditioners of the type which depend (i.e., extend downwardly) along the outside of a building wall below a window or other opening in the building provide a number of advantages as compared to the typical window mounted air conditioner which has substantially no part depending below the bottom of the window. Such advantages are generally known and include such things as low noise level, limited obstruction of the viewing area of the window, and the potential for a relatively high capacity rating without the increase in physical size of the unit being observable from inside the room. However, to the extent that such units have been proposed as evidenced by the patents listed, and even with the substantial advantages afiorded by such units, they have not been commercially successful to any large degree so far as we know.

For a room air conditioner to achieve commercial success under prevailing marketing conditions, a number of requirements should be met by the air conditioner. Among such requirements are that its cost be compatible with its capacity rating, that it be of a reasonable size for the rating, that its performance characteristics be comparable with other room air conditioners of about the same cost, that it be of a character that it may be installed without undue difficulty in its intended location, and that it be arranged to afford reasonably convenient servicing. The outside mounted room air conditioner with which this invention is concerned is one which is highly developed to meet the requirements above, and holds the promise of capturing a reasonable part of the market.

The room air conditioner unit according to this invention is, however, of a premium character in that it is relatively expensive as compared to other room air conditioners of the same capacity but which are of more or less standard construction and do not include special features. To justify the purchase of an air conditioner according to the invention, it accordingly must possess some special advantages. One such special advantage is the relative quietness of the room air conditioner, which is in part due, of course, to the main section being located entirely outside of the building, and in part to a low turbulence airflow path for the room air. Also the unit lends itself to creating a relatively low profile as observed from within the room.

SUMMARY OF THE INVENTION Accordingly this invention deals generally with the general structural arrangement of the main section, and in particular with the structural arrangement of parts in the room air section. Essentially, the room air section includes the same general components as found in the room air section of ordinary room air conditioners. 1n the upper or room air section of a unit according to the invention, a pair of centrifugal fans are provided in the lower portion of the section with the axes of the fans horizontal and parallel to the building wall, the fan housings for the fan being disposed in an upblast disposition, and duct means are coupled to the discharge openings of the fan housings to carry the discharged air from the fans up wardly and then forwardly into the area upstream of the evaporator, the duct means including expanding walls in this area so that the airflow from the fans will be distributed across the entire upstream face of the refrigerant evaporator. The evaporator is located to extend across substantially the entire width of the room air section and in registry with an opening in the upper portion of the inner wall of the room air section.

In accordance with a currently preferred embodiment of the invention, the duct means leading from the centrifugal fans to the evaporator is a formed, single piece (i.e., monolithic piece) which also includes the evaporator drip pan. The assembly of fan housings, duct means and evaporator pan serves in large part to separate the interior of the room air section into the pressurized airspace for the air being forced to the evaporator for conditioning, and the suction airspace through which air is returned from the lower part of the duct section to the fans.

With the arrangement as described both the inlets to the fan housings, and the fan housing discharge openings lie in planes which are not perpendicular or normal to a line of sight looking directly through the duct section passages. This arrangement, coupled with the location of the evaporator relative to the fans, is believed to contribute materially to the relatively low noise rating of the unit.

DRAWING DESCRIPTION FIG. 1 is an isometric view of a room air conditioner according to the invention as viewed from outside the building;

FIG. 2 is a side elevational view of the room air conditioner in mounted relation to the building and with broken outlines illustrating the general arrangement of the parts of the interior of the unit;

FIG. 3 is a partly-broken elevational view of the interior parts of the upper or room air portion of the main section with the wrapper or casing removed;

FIG. 4 is a perspective view of the main section in assembled form and with the wrapper omitted;

FIG. 5 is an exploded perspective view of the room side section;

FIG. 6 is a perspective view of the outside air section;

FIG. 7 is a vertical sectional view corresponding to one taken along line 7-7 of FIG. 5; and

FIG. 8 is a perspective view of an installation in which the room air section and outside air section are arranged in sideby-side relation.

DESCRIPTION OF THE PREFERRED EMBODIMENT The room air conditioner of FIG. 1 is mounted with the main section 10 depending along the outside of a building wall 11, and with the duct section 12 coupled to the opening below the lower rail of a sash of an ordinary double hung or single hung window 113. While as shown in FIGS. 1 and 2 the unit is coupled to the room being conditioned through a window opening, it will be appreciated that the unit may also be installed in a through-the-wall arrangement in which an opening is cut in the wall 1 l and the duct extends therethrough into the room.

A typical lower story window mounting arrangement is shown in FIG. 2, the details with respect thereto, and also with respect to an upper story mounting arrangement, being found in the noted Ulich patent application.

The main section 10 is of generally rectangular, box shape (right parallelepiped) and includes an upper, room air section 115, and a lower, outside air section 16 separated by a horizontal wall 17 which supports the main parts of the room air section.

The main section contains the refrigeration system components and the airflow components which together contribute most of the weight of the unit. The general locations of these components within the main section are designated by the dashline outlines in FIG. 2 and include a refrigerant compressor 18, condenser 19, and a condenser fan driven by electric motor 21, all of these enumerated components being in the lower part of the main section, which has been termed the outside air section 16, as illustrated. The upper, or room air section 15, of the main section is separated from the lower part by the noted wall 17 and contains a pair of centrifugal fans 22 in scroll-shaped housings 23, the fans 22 being driven by oppositely projecting shafts of electric motor 24 located between the fan housings. The fan housings 23 are disposed in an upblast disposition with the outlet 25 of each housing being connected by a duct 26 extending upwardly and then forwardly to deliver air from the fan to the upstream face 27 of the refrigerant evaporator 28 which is located to extend across substantially the entire width of the room air section and is located in the upper, inner corner of the section. The room air section is made weather tight and all of the walls forming the section, save for the lower one, have thermal insulation on their inner faces. The lower wall has thermal insulation on its lower face.

The duct section 12 comprises four outer walls and an intermediate wall 29 to form a pair of open-ended passages 30 and 31,.which are the conditioned air, and return air, passages, respectively. The outer end of the duct section has its top wall flared upwardly and its bottom wall flared downwardly to define a total opening which registers with and is attached in substantially sealed relation to the open, upper, inner face portion 32 of the room air section. The inner end of the duct section mounts an openwork decorative front and closure assembly 33 which preferably is of the general character disclosed in Appel U.S. Pat. application 685,698, now U.S. Pat. No. 3,476,033 and Ulich U.S. Pat. application 685,699, now U.S. Pat. No. 3,476,034.

As indicated by the arrows in FIG. 2, return air from the room passes through the room air passage 31 and into the room airspace of the main section by the fans 22. The fans draw the air into the housings and force it through the duct work 26 to the expanded space plenum on the upstream side of the evaporator 28 from whence it passes through the evaporator and theconditioned air passage 30 of the duct section back to the room. As noted in the Ulich 5I7 patent application, the duct section walls are preferably of a material providing substantial thermal insulation between the interior and exterior of the duct section, as well as between the two passages in the duct section.

The arrangement of the components of the room air section and their construction are probably best evident from-FIGS. 3-5. The room air fan motor 24 is supported independently from the base wall 17 by a pair of brackets 34 (one shown in FIG. 5). Each fan housing includes a generally flat bracket 35 disposed in an upright disposition and having a lower flanged edge secured to the wall 17. The opposite sidewall and the scroll portion of the fan housing 23, in its currently preferred form, is a formed plastic member 230. The inlet openings to the housing in both the bracket 35 and the formed plastic housing side are of equal size. Also, while not wholly apparent in FIG. 5, the inlet openings of the housings facing the fan motor 24 are spaced sufficiently from the ends of the fan motor to permit substantially unimpeded and aerodynamically smooth airflow into these inner openings. Also of course, the openings facing the sidewalls of the main section are spaced sufl'rciently from the sidewalls to permit unimpeded flow into the openings.

The plastic, formed scroll 23a is flanged along several of its edges, as at 36 for fastening the scroll to the upright bracket. It is also flanged along its top edge adjacent the cutoff 37 and along the side to provide part of the base upon which the duct work will seat. It will be noted that both of the fan housings are formed in identical manner, and in each case as shown in FIG.

5 the upright bracket 35 is on the left and the scroll housing is fastened to the right side of the bracket.

The space for the electrical components such as motor starting capacitors and terminal blocks, and the mountings therefor is provided by an upstanding, outwardly open channel 38 which is secured along its bottom edges to the wall 17. A wiring harness 39 connects the control box 40 to the components mounted on the channel. The control box 40 is shown in FIG. 4 in its position for shipping, and is shown in its operative location accessible at the decorative front 33 in FIG. 2.

An opening 41 in the bottom wall 17 is provided with an. overlying cable operated damper 42 to control the admission of outside air into the room airspace.

In accordance with the currently preferred embodiment of the invention, the duct means 26 leading from the upblast discharge openings 25 of the fan housings is provided by a single-molded, plastic part which forms the ducts for both of the fan outlets, as well as providing support means for the evaporator 28 and the drip pan 43 for the evaporator. As may be seen in FIGS. 5 and 7, each duct 26 includes a curved rear and upper wall 44 and opposite sidewalls which include flat portions 45 and outwardly flared

forward portions

46 and 47 which provide a laterally expanding air passage as the air approaches the upstream face 27 of the evaporator. The single, formed member also includes a downwardly inclined portion 48 (FIG. 7) located immediately forward of the location of the cutoff 37 of the fan housings. The forward continuation of this downwardly inclined portion 48 constitutes the drip pan'43 with an upright lip 49 being formed on the front edge of the drip pan. A gasket 50 is secured to the front face of the lip 49, and a slab of thermal insulation 51 underlies the drip pan 43. At the forward edge of the flared portion 46 'of the duct means, a bracket portion 52 is provided to serve as a base for attaching the edge plates 53 of the evaporator, the formed member then continuing laterally at both sidesto block off the space within which the return bends of the evaporator are located. The two flared inner wall portions 47 are connected by a flat portion 54 to which is adhesively secured a rigid foam piece 55 which is triangular in horizontal section and serves as a continuation of the flared portions 47 to prevent turbulence and noise. From the foregoing description it will be appreciated that the single, monolithic, member which forms the duct means 26 for each fan also serves to support the evaporator, and to form the evaporator drip pan. Each of the duct means 26 is expanded both laterally by the flared

portions

46 and 47, as well as downwardly by the wall 48 to facilitate the distribution of air across the entire width and height of the evaporator 28 by the time the air reaches the upstream face 27 of the evaporator.

The top of the duct means is closed by the downwardly open, U-shaped outer wrapper (FIG. 1) which includes the top wall 56, and opposite sidewalls 57. The inner face of all of the walls of the wrapper are provided with thermal insulation.

Referring again to FIGS. 3-5, a lower front wall 58 extends upwardly from the front edge of the horizontal wall 17 forming the base of the room air section. The top edge of this wall 58 serves to define the lower edge of the opening 32 defining the upper, inner face of the room air section, and which is sized to be in registry with the outer end of the duct section 12. The side edges and upper edge of this opening 32A is defined by the edges of the

wrapper walls

56 and 57. The air filter 59 (FIG. 4) extends for the entire width of the unit and from the lower surface of the drip pan 43 down to the upper surface of the bottom wall 17.

It will be appreciated from the foregoing that the space in the room air section is basically divided, with respect to airflow, into the pressurized airspace on the discharge side of the fans and leading to the evaporator, and the remainder of the space which constitutes all that space through which air may flow in its way to the fans. In other words, the air is confined only in its way from the fans to the evaporator, with the remainder of the space simply serving to permit the return air to flow to the fans.

The arrangement of parts in the outside air section is illustrated in FIG. 6. The condenser 19 in that arrangement occupies the width and height of the outer wall of the section with a louvered panel 60 (FIG. ll) overlying the face of the condenser. A formed shroud 61 with a fan ring (not shown) is provided on the inner face of the condenser. The condenser fan 21 is mounted to the inner wall 62 of the outside air section to properly locate the fan 20 within the ring. The compressor 18 is mounted on the base wall of the outside section and to the side as illustrated in FIGS. 4 and 6. Both the electrical connections, and the refrigerant conducting line connections pass through the wall 17 at the base of the room air section at appropriate locations as illustrated in FIG. 4.

The unit as assembled and with its wrapper on is mounted to a windowsill as shown in FIG. 2 in accordance with the details set forth in the first-noted Ulich patent application. Then, in accordance with that application the duct section 12 is connected to the main section so that the outer open end 32 of the duct section registers with the opening on the upper inner face of the room section. As such, the outer edge of the intermediate wall 29 seats against the gasket 50 on the front lip of the evaporator drip pan, while the lower edge of the outer open end of the duct section seals against a similarly placed gasket on the upper edge of the stub wall 58. The side edges of the outer open end of the duct section seat against the vertical edges of the wrapper, while the top edge of the duct section seats against the inner horizontal top edge of the wrapper.

The unit may also be installed in a through the wall arrangement in which a wall sleeve is provided and the main section is hung from a support plate carrying brackets. The duct section is slightly modified in such an' installation, but the overall relation of main section and duct section is substantially the same.

In the embodiment shown in FIG. ll outside air is drawn into the opposite side louvers 63 of the wrapper and forced out through the louvered panel 60. The airflow through the duct section and room air section is as noted before.

The disposition of the fans as illustrated with their axes parallel with the building wall and horizontal, and with the opposite side inlets and upblast discharge results in both the inlets and the fan discharge outlets lying in planes which are not perpendicular to a direct line of sight from inside the room toward the unit. It is believed that this arrangement contributes in part to the relative quietness of the unit in operation. Also, the location of the evaporator in the path of the discharge air but at the outer end of the duct section is be lieved to reduce air noise. Of course the duct section itself also contributes to a deadening of the noise.

Upon consideration it will be further appreciated that the provision of the room air section components supported independently upon its own base wall 17, and the outside air section components supported on the base wall 17 and the front wall 62 lends itself to changing the basic configuration of the unit from one in which the room air section is stacked upon the outside air section, to one in which the sections are sideby-side. The only requirement of significance is to provide a different wrapper arrangement for each section, and to extend the refrigerant conducting lines and electrical lines between different points. The use of an evaporator which is in the upper, inner corner of the room section results in the drip pan being situated above the bottom wall 17 of the room air section so that a gravity condensate drain may still be used even though the room air section and outside air section are in sideby-side relation. The condenser airflow path may also be changed when the sections are in side-by-side relation by providing the air openings in another part of the outside air section wrapper. Thus, in summary, the basic arrangement is not only eminently satisfactory for a unit in which the room air section and the outside air section are stacked on each other, but also lends itself to utilizing the sections in a modular fashion in which the sections are in side-by-side relationship either inside or outside the building. An example of a side-byside arrangement in which the unit is coupled to an opening in a building wall rather than a window opening as illustrated in FIG. 8. Where the outer face of the outside air section is the only face available for both the intake and exhaust of condenser air, that face is separated into the two parts and the condenser is sized to occupy only the one part.

We claim as our invention:

l. A room air conditioner comprising:

a main section of substantially right-parallelepiped-shape containing an upper room air section, and a lower outside air section in stacked relationship with each other and separated by a generally horizontal wall therebetween, said main section being adapted to be positioned in an upright disposition along the outside of a wall of the room to be conditioned, said upper room air section having at least the upper portion of its inner lface substantially open for the width of said main section;

a separable duct section connecting said open face with an opening in said building wall, said duct section including an intermediate level wall therein separating said duct section into a lower return air passage, and an upper conditioned air passage;

said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion of said room air section in spaced-apart relation, and with their axes generally horizontal and parallel to said building wall, a refrigerant evaporator coil extending across the upper portion of the opening in said room air section, and for substantially the entire width of said main section, the lower edge of said coil being on a level substantially meeting the outer edge of said intermediate level wall of said duct section; and

means in said room air section defining a passage from the outlets of said fans to the upstream face of said coil.

2. A room air conditioner according to claim ll wherein:

each of said pair of said fans is of the double-inlet, scroll type, both of said fans being driven by a single motor located between said fans.

3. A room air conditioner according to claim ll wherein:

said means defining said passage from the outlets of said fans to the upstream face of said coil comprises a separate duct section for each fan connected to the upblast opening of each fan for confining the upwardly directed discharge of air from each fan and then turning it toward the upstream face of said evaporator coil, each of said ducts including laterally flared end portions to expand the width of the airflow space to substantially the entire width of said evaporator coil at a location generally coincident with the upstream face of said evaporator coil.

4!. A room air conditioner according to claim 3 including:

a condensate pan for said evaporator coil, said condensate pan and said means defining a passage from the outlets of said fans to the upstream face of said coil comprising a monolithic, formed section of a plastic material.

A room air conditioner comprising:

a main section of substantially a rectangular box-shape comprising a room air section and an outside air section, each of said sections having a separate bottom wall dimensionally substantially equal to each other, and a cubic size substantially equal to each other, and a cubic size substantially equal to each other to accommodate selectively placing said sections in stacked, and side-byside relation, said room air section including means defining an opening located in the upper portion of the inner wall thereof;

duct means for coupling said room air section opening to an opening in a wall of a building to be conditioned, said duct means including an upper conditioned air passage, and a lower return air passage;

said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion thereof in spaced apart relation and with their axes generally horizontal and parallel to said building wall, a motor in said room air section for driving said fans, a refrigerant evaporator coil extending across the upper part of said opening in said room air section and for substantially the entire width of said room air section, said evaporator coil substantially registering with said upper conditioned air passage in said duct means; and

means defining an expanding air passage between said centrifugal fans and the upstream face of said evaporator coil.

6.- A room air conditioner comprising:

a main section of substantially rectangular box-shape comprising a room air section and an outside air section in stacked relationship, each of said sections including an independent bottom wall of substantially equal rectangular dimensions, both of said sections being of substantially equal cubic size, said room air section including means defining an opening located in the upper portion of the inner wall thereof providing an opening for communication of air between said room air section and the room to be conditioned;

a duct section for coupling said room air section opening to an opening in a wall of a building to be conditioned, said duct section including an upper conditioned air passage, and a lower return air passage;

said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion thereof in spaced apart relation and with their axes generally horizontal and parallel to said building wall, a motor in said room air section for driving said fans, a refrigerant evaporator coil extending across the upper part of said room air section opening and for substantially the entire width, said coil being in substantial registry with said upper conditioned air passage in said duct section; and

7. A room air conditioner according to claim 6 wherein:

said means defining said expanding air passage from said centrifugal fans to said evaporator includes integrally formed means for supporting said evaporator and providing an evaporator drip pan underlying said evaporator.

8. A room air conditioner according to claim 7 wherein:

said centrifugal fans include scroll shaped housing means, each of said housing means includes an upright metallic wall of generally planar form having its lower edge secured to the bottom wall of said room air section, the remainder of said scroll shaped housing essentially comprising a formed member supported solely from said upstanding wall forming an opposite side of said housing;

said means forming said expanded passageway and said evaporator support and evaporator drain pan being supported by said fan housings and said upright walls.

Claims

1. A room air conditioner comprising: a main section of substantially right-parallelepiped-shape containing an upper room air section, and a lower outside air section in stacked relationship with each other and separated by a generally horizontal wall therebetween, said main section being adapted to be positioned in an upright disposition along the outside of a wall of the room to be conditioned, said upper room air section having at least the upper portion of its inner face substantially open for the width of said main section; a separable duct section connecting said open face with an opening in said building wall, said duct section including an intermediate level wall therein separating said duct section into a lower return air passage, and an upper conditioned air passage; said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion of said room air section in spaced-apart relation, and with their axes generally horizontal and parallel to said building wall, a refrigerant evaporator coil extending across the upper portion of the opening in said room air section, and for substantially the entire width of said main section, the lower edge of said coil being on a level substantially meeting the outer edge of said intermediate level wall of said duct section; and means in said room air section defining a passage from the outlets of said fans to the upstream face of said coil.

2. A room air conditioner according to claim 1 wherein: each of said pair of said fans is of the double-inlet, scroll Type, both of said fans being driven by a single motor located between said fans.

3. A room air conditioner according to claim 1 wherein: said means defining said passage from the outlets of said fans to the upstream face of said coil comprises a separate duct section for each fan connected to the upblast opening of each fan for confining the upwardly directed discharge of air from each fan and then turning it toward the upstream face of said evaporator coil, each of said ducts including laterally flared end portions to expand the width of the airflow space to substantially the entire width of said evaporator coil at a location generally coincident with the upstream face of said evaporator coil.

4. A room air conditioner according to claim 3 including: a condensate pan for said evaporator coil, said condensate pan and said means defining a passage from the outlets of said fans to the upstream face of said coil comprising a monolithic, formed section of a plastic material.

5. A room air conditioner comprising: a main section of substantially a rectangular box-shape comprising a room air section and an outside air section, each of said sections having a separate bottom wall dimensionally substantially equal to each other, and a cubic size substantially equal to each other, and a cubic size substantially equal to each other to accommodate selectively placing said sections in stacked, and side-by-side relation, said room air section including means defining an opening located in the upper portion of the inner wall thereof; duct means for coupling said room air section opening to an opening in a wall of a building to be conditioned, said duct means including an upper conditioned air passage, and a lower return air passage; said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion thereof in spaced apart relation and with their axes generally horizontal and parallel to said building wall, a motor in said room air section for driving said fans, a refrigerant evaporator coil extending across the upper part of said opening in said room air section and for substantially the entire width of said room air section, said evaporator coil substantially registering with said upper conditioned air passage in said duct means; and means defining an expanding air passage between said centrifugal fans and the upstream face of said evaporator coil.

6. A room air conditioner comprising: a main section of substantially rectangular box-shape comprising a room air section and an outside air section in stacked relationship, each of said sections including an independent bottom wall of substantially equal rectangular dimensions, both of said sections being of substantially equal cubic size, said room air section including means defining an opening located in the upper portion of the inner wall thereof providing an opening for communication of air between said room air section and the room to be conditioned; a duct section for coupling said room air section opening to an opening in a wall of a building to be conditioned, said duct section including an upper conditioned air passage, and a lower return air passage; said room air section including a pair of upblast-disposed, centrifugal fans located in the lower portion thereof in spaced apart relation and with their axes generally horizontal and parallel to said building wall, a motor in said room air section for driving said fans, a refrigerant evaporator coil extending across the upper part of said room air section opening and for substantially the entire width, said coil being in substantial registry with said upper conditioned air passage in said duct section; and means defining an expanding air passage between said centrifugal fans and the upstream face of said evaporator coil.

7. A room air conditioner according to claim 6 wherein: said means defining said expanding air passage from said centrifugal fans to said evaporator inclUdes integrally formed means for supporting said evaporator and providing an evaporator drip pan underlying said evaporator.

8. A room air conditioner according to claim 7 wherein: said centrifugal fans include scroll shaped housing means, each of said housing means includes an upright metallic wall of generally planar form having its lower edge secured to the bottom wall of said room air section, the remainder of said scroll shaped housing essentially comprising a formed member supported solely from said upstanding wall forming an opposite side of said housing; said means forming said expanded passageway and said evaporator support and evaporator drain pan being supported by said fan housings and said upright walls.