WO2014101222A1

WO2014101222A1 - Hvac indoor unit and method of making

Info

Publication number: WO2014101222A1
Application number: PCT/CN2012/088117
Authority: WO
Inventors: Shunhua Wang; Longmei ZHOU; Xin Li; Hao Li
Original assignee: Trane Air Conditioning Systems (China) Co., Ltd.
Priority date: 2012-12-31
Filing date: 2012-12-31
Publication date: 2014-07-03
Also published as: CN105008808A; CN105008808B

Abstract

A HVAC indoor unit comprising a coil housing (110) configured to house a heat exchange coil (112) and a plenum chamber (120) attached to the coil housing (110) is disclosed. Each side panel (110a, 110b) of the coil housing (110) has an elongated "L" shaped tail (111), which includes a back attachment section (111a) and a side attachment section (111b), a fan panel (131) is attached to the back attachment section (111a), and the plenum chamber (120) is attached to the side attachment section (111b). A top panel (110t) of the coil housing (110) has one or more slots (118) matched with one or more tabs (128) of a top panel (120t) of the plenum chamber (120). A filter (122a, 122b) can be retained to the plenum chamber (120) by one or more "L" shaped retaining pins (123).

Description

HVAC INDOOR UNIT AND METHOD OF MAKING

Field

The disclosure herein generally relates to a heating, ventilation, and air-conditioning ("HVAC") system, and more particularly to a HVAC indoor unit of the HVAC system.

Generally, methods, systems, and apparatuses are described that are directed to a HVAC indoor unit including a coil housing that is assembled from a plurality of panels, such as side, top and/or bottom panels. Background

HVAC indoor unit including heat exchange coils have been used in a HVAC system.

The HVAC indoor unit typically includes a coil housing that is configured to accommodate a plurality of heat exchange coils, which are typically configured to carry a refrigerant or a process fluid (such as water conditioned by the HVAC system). A fan assembly, which may include a fan and a fan panel, can be typically installed on the coil housing. The fan can be configured to move air across outer surfaces of the heat exchange coils, such that the air can be conditioned by the refrigerant or the process fluid carried in the heat exchange coils.

The coil housing sometimes can be assembled from a plurality of side, top and/or bottom panels. The fan can be attached to the fan panel that is configured to be attached to the coil housing. In some configurations, the fan assembly can be housed inside a plenum chamber, which may be configured to be assembled from a plurality of side, top and/or bottom panels.

The plenum chamber can be attached to the coil housing and configured to include a filter for the heat exchange coil assemblies.

Summary

A HVAC indoor unit generally includes a coil housing configured to house a heat exchange coil(s). The coil housing can sometimes be connected to a plenum chamber, which may be configured to house a fan assembly and/or a filter of the HVAC indoor unit. In some embodiments, the coil housing may include a fan attachment section and a plenum attachment section. The fan attachment section may be configured to receive a fan panel of a fan assembly. In some embodiments, the fan attachment section may be located on a back side of the coil housing. The plenum attachment section may be configured to receive a plenum chamber. The fan attachment section and the plenum attachment section may be configured to be separate from each other. The fan and plenum attachment sections may be configured so that the attachment of a plenum chamber to the plenum attachment section does not interfere with the attachment or removal of the fan assembly.

In some embodiments, the fan panel can be attached to the fan attachment section by a fan mounting mechanism. In some embodiments, the plenum chamber can be attached to the plenum attachment section by a plenum mounting mechanism. In some embodiments, the fan mounting mechanism may be configured to be away from the plenum mounting mechanism so that the plenum mounting mechanism does not interfere with the fan mounting mechanism.

In some embodiments, the coil housing may include a plurality of panels, such as a side panel, a top panel and a bottom panel. In some embodiments, the side panel may include an elongated "L" shaped tail, which includes a back attachment section and a side attachment section.

In some embodiments, the fan panel of the fan assembly can be attached to the back attachment section; and a side panel of a plenum chamber can be attached to the side attachment section. In some embodiments, the fan panel and the side attachment section of the "L" shaped tail has a space configured to accommodate a mounting mechanism for the panel of the plenum chamber.

In some embodiments, the top panel of the coil housing may be configured to have one or more slots that are configured to engage matching tabs of a top panel of a plenum chamber. The engagement of the tabs and the slots can help retain the top panel of the plenum chamber on the top panel of the coil housing.

In some embodiments, the plenum chamber is configured to receive a filter. The filter may be retained on the plenum chamber by one or more retaining pins. In some embodiments, the retaining pin(s) may include a long arm and a short arm, each of which is configured to accommodate different thicknesses of the filters. In some

embodiments, the long arm may be configured to include a first hook; and the short arm may be configured to include a second hook. The first and second hooks may be configured to catch a panel of the HVAC indoor unit, respectively.

In some embodiments, when the first hook is used to catch a panel of the HVAC indoor unit, the short arm is used to retain a filter of a first thickness; and when the second hook is used to catch a panel of the HVAC indoor unit, the long arm is used to retain a filter of a second thickness.

In some embodiments, the long arm and the short arm may include a mounting aperture with a first diameter, and the panel of the plenum chamber may include a catching aperture with a second diameter, and the first diameter is larger than the second diameter. In some

embodiments, the first diameter of the mounting aperture is configured to allow a mounting mechanism to rotate freely, while the second diameter of the catching aperture is configured so that the catching aperture can catch the mounting mechanism.

Other features and aspects of the embodiments will become apparent by consideration of the following detailed description and accompanying drawings.

Brief Description of the Drawings

Reference is now made to the drawings in which like reference numbers represent corresponding parts throughout.

Figs. 1 A to ID illustrate different views of a HVAC indoor unit. Fig. 1 A is a perspective view of the HVAC indoor unit. Fig. IB is a partial exploded view of the HVAC indoor unit. Fig. 1C illustrates a perspective exploded view of a fan assembly including a fan and a fan panel. Fig. ID is a back view of the fan panel.

Figs. 2A to 2D illustrate different partial views of a side panel of the coil housing, a side panel of a plenum chamber, and a fan panel. Fig. 2A is a partial perspective view. Figs. 2B and 2C are top views. Fig. 2D is a bottom perspective view. Fig. 3 is a perspective view of a partially dissembled HVAC indoor unit.

Figs. 4A to 4F illustrate different aspects of a top panel of a coil housing and a top panel of a plenum chamber. Fig. 4A illustrates a perspective view of a top panel of a coil housing. Fig. 4B is an enlarged view of a slot of the top panel of the coil housing. Fig. 4C illustrates a perspective view of a top panel of a plenum chamber. Fig. 4D is an enlarged view of a tab of the top panel of the plenum chamber. Fig. 4E illustrates a perspective view showing the top panel of the coil housing connected to the top panel of the plenum chamber. Fig. 4F is a side view showing the top panel of the coil housing connected to the top panel of the plenum chamber.

Figs. 5A to 5E illustrate different aspects of a retaining pin. Fig. 5A illustrates a perspective view of the retaining pin. Fig. 5B illustrates a side view of the retaining pin. Fig. 5C illustrates the retaining pin being used with a relatively thin filter. Fig. 5D illustrates the retaining pin being used with a relatively thick filter. Fig. 5E illustrates that the hook of the retaining pin is mounted to the retaining cavity of a panel. Fig. 5F illustrates a retaining cavity of a panel that can be caught by a hook of the retaining pin.

Detailed Description

HVAC indoor units may include a coil housing that houses heat exchange coils. A fan assembly (including, for example, a fan and a fan panel) can be attached to the coil housing. The fan can be configured to move air across outer surfaces of the heat exchange coils, so that the air can be conditioned by a fluid carried inside the heat exchange coils. The fan assembly may be housed in a plenum chamber, which can also be configured to include an air filter(s). The plenum chamber typically can be attached to the coil housing.

The coil housing and/or the plenum chamber can be assembled from a plurality of panels, such as top, bottom and side panels. Sometimes, the panels of the coil housing and the plenum chamber have to be dissembled so that the fan and/or the heat exchange coils can be accessed, for example, for cleaning. Improvements can be made to simplify a manufacturing process of the coil housing and/or plenum chamber. Improvements can also be made to simplify the dissembling process, for example, to detach the fan assembly so that the fan assembly, and/or the heat exchange coils can be, for example, cleaned.

Embodiments as described herein are generally related to methods, systems and apparatuses of a HVAC indoor unit that includes a coil housing and a plenum chamber. In some embodiments, a coil housing may be configured to have a fan attachment section that is separate from a plenum attachment section, so that a plenum mounting mechanism does not interfere with a fan mounting mechanism. In some embodiments, a side panel of the coil housing may have an elongated "L" shaped tail including a side attachment section and a back attachment section. A fan of the HVAC indoor unit may be attached to a fan panel. In some embodiments, the fan panel is configured to be attached to the back attachment section of the "L" shaped tail by a mounting mechanism (e.g. self-tapping screws), which allows the mounting mechanism to be disengaged from a back side of the coil housing so that the fan panel and the attached fan can be removed from the coil housing easily. In some embodiments, the top panel of the coil housing may be configured to have one or more slots that are configured to engage matching tabs of a top panel of the plenum chamber. In some embodiments, the top panel of the plenum chamber may be configured to be positioned partially on top of the top panel of the coil housing, and the engagement of the tabs of the top panel of the plenum chamber and the slots of the top panel of the coil housing can help retain the top panel of the plenum chamber on the top panel of the coil housing. In some embodiments, the plenum chamber is configured to receive a filter. The filter may be retained on the plenum chamber by one or more of retaining pins. In some

embodiments, the retaining pin(s) may be configured to have an "L" shaped profile with a long arm and a short arm. In some embodiments, each of the long arm and the short arm are configured to have a hook to engage a panel of the plenum chamber. When the long arm is used to engage the panel of the plenum chamber, the short arm may be configured to hold the filter. When the short arm is used to engage the panel of the plenum chamber, the long arm may be configured to hold the filter. By using either the long arm or the short arm to engage the panel of the plenum chamber, the retaining pin can be configured to accommodate filters with different thicknesses. Embodiments as disclosed herein also include other features that may help simplify assembling or dissembling the coil housing, the fan/fan panel, and/or the plenum chamber. References are made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration of the embodiments in which the embodiments may be practiced. It is to be understood that the terms used herein are for the purpose of describing the figures and embodiments and should not be regarding as limiting the scope of the present application.

Figs. 1 A and ID illustrate different aspects of a HVAC indoor unit 100. As illustrated in

Fig. 1 A, which illustrates a perspective view of the HVAC indoor unit 100, the HVAC indoor unit 100 generally includes a coil housing 110, a plenum chamber 120 that is attached to the coil housing 1 10, a fan 130 that is enclosed by the plenum chamber 120. The coil housing 110 may be configured to house heat exchange coils 1 12. The coil housing 110 and the plenum chamber 120 can be configured to have ceiling mounting apertures 1 15 and 125 respectively. The ceiling mounting apertures 115 and 125 may be used to mount the HVAC unit 100 to, for example, a ceiling of a room.

Fig. IB illustrates the HVAC indoor unit 100 with a partial exploded view of the plenum chamber 120 of Fig. 1A. The plenum chamber 120 is configured to be assembled from a plurality of panels including: side panels 120a and 120b, a top panel 120t and a bottom panel

120d. The plurality of panels 120a, 120b, 120t and 120d can be configured to form a box-shaped plenum chamber 120 to house the fan 130. The fan 130 is attached to a fan panel 131.

A filter 122 can be attached to the plenum chamber 120 by one or more retaining pins 123. The retaining pins 123 can be configured to engage retaining cavities 124 on the side panels 120a and/or 120b of the plenum chamber 100. The retaining pins 123 can also be configured to engage the filter 122 so as to retain the filter 122 on the plenum chamber 120.

The coil housing 1 10 as shown in Fig. 1 A may also be configured to be assembled from a plurality of panels including: side panels 1 10a and 110b, a top panel 11 Ot and a bottom panel and/or drainage panel 1 lOd. The coil housing 1 10 may be configured to house the heat exchange coils 112.

As illustrated in Fig. IB, for the purpose of description herein, the coil housing 110 is configured to have a front side 110F, a back side HOG, a left side 110L and a right side 110R. The plenum chamber 120 is configured to have a front side 120F, a back side 120G, a left side 120L and a right side 120R.

Fig. 1 C illustrates a perspective exploded view of the fan 130 and the fan panel 131. Fig. 1 D illustrates a back view of the fan panel 131.

The fan 130 is typically attached to the fan panel 131 to form a fan assembly 300. The fan panel 131 has an opening(s) 132, which can be configured to be in fluid communication with an air outlet(s) 133 of the fan 130.

Referring to Fig. ID, the fan panel 131 is configured to have a plurality of fan panel mounting apertures 135. The fan panel 131 can be attached to the coil housing 110 by using a mounting mechanism, such as self-tapping screws, to mount the fan panel 131 to the coil housing 110 through the fan panel mounting apertures 135. As shown in Fig. IB, the fan 130 and the fan panel 131 can be mounted to the back side 1 10G of the coil housing 110.

As illustrated in Figs. IB, 1C and ID, relative to the coil housing 110, the plurality fan panel mounting apertures 135 are configured to be coupled to the back side 1 10G of the coil housing 1 10.

As illustrated in Figs. 1 A to ID, the panels, including 1 10a, 1 10b, 1 lOt, 1 lOd, 120a,

120b, 120t, 120d and 131 can be constructed from a sheet material, such as sheet metal.

In operation, the fan 130 can drive air to move across the filter 122 to get into the plenum chamber 120. The fan 130 can then drive the air to move into the coil housing 110 from the back side HOG of the coil housing 1 10. The air can be driven across the heat exchange coils 112 inside the coil housing 1 10, so that the air can be conditioned by the heat exchange coils 1 12.

Figs. 2 A to 2D illustrate different partial views of the HVAC indoor unit 100 as illustrated in Fig. 1 A. Particularly, a portion of the side panel 120a, a portion of the fan panel 131 and a portion of the side panel 1 10a are shown. The fan panel 131 is mounted to the side panel 110a of the coil housing 110. It is noted that the partial views only show the left side of the HVAC indoor unit 100, it will be appreciated that the right side of the air condition indoor unit 100 can be similarly configured.

Referring to Fig. 2A and the orientations of the coil housing 110 and the plenum chamber 120 as set up in Fig. IB, the fan panel 131 is attached to the side panel 1 10a of the coil housing 110 from the back side 1 10G of the coil housing 110. The fan panel 131 can be attached to the side panel 110a by a fan mounting mechanism 210a through the fan mounting aperture 135, which can be, for example, a self-tapping screw.

The side panel 120a of the plenum chamber 120 is attached to the side panel 110a of the coil housing 1 10 from the left side 110L of the coil housing 110. The side panel 120a of the plenum chamber 120 can be attached to the side panel 110a by a plenum mounting mechanism 210b, which can be, for example, a self-tapping screw. The side panel 120a of the plenum chamber 120 is not mounted to the fan panel 131. The plenum mounting mechanism 210b is configured to be away from the fan mounting mechanism 210a, so that the plenum mounting mechanism 210b does not interfere with the mounting or removal of the fan panel 131.

Referring to Figs. 2B and IB, the side panel 110a of the coil housing 1 10 has an elongated tail 111. The elongated tail 111 has a back attachment section 111a and a side attachment section 11 lb. In the illustrated orientation as shown in Fig. 2B, the back attachment section 11 1a and the side attachment section 111b form an "L" shaped elongated tail 111. In the orientation as shown in Fig. 2B, the back attachment section 11 la extends in a direction from the right side 1 1 OR to the left side 1 10L of the coil housing 110 as shown in Fig. IB. The back attachment section 11 la is followed by the side attachment section 11 lb, which extends in a direction from the front side 11 OF to the back side HOG into the plenum chamber 120, when the plenum chamber 120 is attached to the back side 1 10G of the coil housing 1 10. For example, the side attachment section 11 1b extends relatively in a direction from the front side 120F to the back side 120G of the plenum chamber 120.

As illustrated, the fan panel 131 is attached to the back attachment section 11 1a from the back side 1 10G of the coil housing 110. The side panel 120a of the plenum chamber 120 is attached to the side attachment section 1 11b from the left side 120L of the plenum chamber 120 by the panel mounting mechanism 210b.

The fan panel 131 has a gap G2 from the side attachment section 1 1 lb. The gap G2 is configured to be large enough to accommodate the plenum mounting mechanism 210b. In some embodiments, for example, when a self-tapping screw is used, the gap G2 is configured to be large enough to accommodate a stem (or head) section of the screw. The gap G2 can prevent the plenum mounting mechanism 210b from interfering with the installation and/or removal of the fan panel 131 from the back attachment section 1 11a.

As illustrated in Fig. 2C, the gap G2 can also be configured to be large enough to accommodate, for example, a side panel accessory 150. In some embodiments, the side panel accessory 150 can be an insulation material. The gap G2 allows the fan panel 131 and/or the side panel accessory 150 to be installed or dissembled without interfering with each other.

Referring to Fig. 2D, a bottom partial perspective view of the HVAC indoor unit 100 is shown. The side panel 120a of the plenum chamber 120 has a raised bottom edgel26. The raised bottom edge 126 is typically configured to be coupled to the bottom panel 120d (as shown in Fig. IB). The raised bottom edge 126 is configured to bend outwardly, i.e. toward the left side 120L of the plenum chamber 120 relative to the side panel 120a. For example, the raised bottom edge 126 of the side panel 120a of the plenum chamber 120 is bent toward an opposite side of the side panel accessory 150 relative to the side panel 120a. The outwardly bent raised bottom edge 126 allows the fan panel 131 to slide into or out of the plenum chamber 120 without the interference of the raised bottom edge 126.

The side panels 110a and 120a, the fan panel 131 can be made from a sheet metal. The shapes of the panels and the edges can be made by bending the sheet metal.

Referring back to Fig. ID, the fan mounting apertures 135 are configured to be coupled to the back side HOG of the coil housing 110. As illustrated in Fig. 2A, the fan panel 131 can be mounted to, the back mounting section 1 1 la of the side panel 110a of the coil housing 110 by the fan mounting mechanism 210a through the fan mounting apertures 135.

In some embodiments, the fan panel 131 is not mounted to the top panel 1 lOt of the coil housing 1 10 and the top panel 120t of the plenum chamber 120. In some embodiments, the fan panel 131 can be also not mounted to any other panels of the plenum chamber 120. The fan 130 and the fan panel 131 can be fully supported in the plenum chamber 120 without being mounted to any panels of the plenum chamber 120.

It is appreciated that in some embodiments, the fan panel 131 can be mounted to the top panel 11 Ot. Generally, the fan panel 131 is only attached to the back side 1 10G of the coil housing 110 by fan mounting mechanism 210a, so that the fan mounting mechanism 210a can be removed from the back side HOG of the coil housing 110.

The side panel 120a (and the side panel 120b) is mounted to the side mounting section 11 lb of the elongated tail 111 of the side panel 110a (and the side panel 110b) of the coil housing 1 10. The side panel 120a (and/or the side panel 120b) is configured so that the mounting of the side panel 120a (and/or the side panel 120b) of the plenum chamber 120 does not interfere with the fan panel 131 when the plenum chamber 120 is attached to the coil housing 1 10. These features allow the attachment of the plenum chamber 120 to the coil housing 110 to not interfere with the installation and/ or removal of the fan panel 131.

Referring to Fig. 3, because the fan panel 131 is mounted on the back side HOG of the coil housing 1 10 by the fan mounting mechanism 210a (as shown in Fig. 2A), the fan mounting mechanism 210a can be removed relatively easily from the back side HOG of the coil housing 110. Therefore, the fan 130 and the fan panel 131 can be installed or removed from the coil housing 1 10 without dismounting the top panel 120t, side panels 120a and/or 120b of the plenum chamber 120.

During an installation process of the fan 130 and the fan panel 131 , the top panel 120t, side panels 120a and 120b of the plenum chamber 120 can be attached to the coil housing 110 first. The fan panel 131 can be moved into position either from a bottom 200 of the plenum chamber 120, or from the back side 120G of the plenum chamber 120. The fan panel 131 can then be mounted to the back side 1 10G of the coil housing 1 10, such as the elongated tail 1 11 of the side panel 110a as shown in Fig. 2A.

Referring back to Fig. IB, during a removal process, the filter 122 and the bottom panel 120d of the plenum chamber 120 can be removed first. The fan panel 131 can then be dismounted by removing the fan mounting mechanism 210a, for example, from the back side 120G of the plenum chamber 120. The fan panel 131 can then be removed from the plenum chamber 120. The installation and removal of the fan panel 131 and the fan 130 generally do not have to involve removing the top panel 120t and/or the side panels 120a/120b of the plenum chamber 120. This may simplify the installation and/or removal of the fan panel 131 and the fan 130 from the HVAC indoor unit 100.

It will be appreciated that the embodiments as disclosed herein are exemplary. In general, the coil housing may be configured to include a fan attachment section and a plenum attachment section. The fan attachment section may be configured to receive a fan panel of a fan assembly. The plenum attachment section may be configured to receive a plenum chamber. In some embodiments, the fan attachment section and the plenum attachment section may be separate, so that a plenum mounting mechanism attaching the plenum chamber to the plenum attachment section of the coil housing is separate from or away from the fan mounting mechanism attaching the fan panel to the fan attachment section. In some embodiments, the fan mounting mechanism for the fan panel does not interfere with the plenum mounting mechanism of the plenum chamber. The fan panel can be install or removed from the coil housing without removing the plenum chamber. In some embodiments, the fan panel can be attached to the back side of the coil housing so that the fan panel can be removed from the coil housing from the back side of the coil housing.

Figs. 4A to 4F illustrate a method and apparatus to engage the top panel 1 lOt of the coil housing 1 10 and the top panel 120t of the plenum chamber 120. Also referring back to Figs. 1 A and IB, the front side 120F of the top panel 120t of the plenum chamber 120 typically engages the top panel 1 lOt of the coil housing 110.

As illustrated in Figs. 4A and 4B, the back side 1 10G of the top panel 1 lOt of the coil housing 1 10 includes one or more slots 118. As shown in Fig. 4B, the slot 118 is typically located along a bent edge 119 of the back side 1 10G of the top panel 1 lOt.

As illustrated in Figs. 4C and 4D, the front side 120F of the top panel 120t of the plenum chamber 120 includes one or more tabs 128. As shown in Fig. 4D, the tab 128 typically includes a break away portion of the front side 120F of the top panel 120t of the plenum chamber 120.

Locations of the slots 1 18 along the back side HOG of the top panel 1 lOt of the coil housing 1 10, and sizes and shapes of the slots 118 are configured to match locations of the tabs 128 along the front side 120F of the top panel 120t of the plenum chamber 120, and sizes and shapes of the tabs 128. The slots 118 can receive the tabs 128.

As shown in Fig. 4E, the tabs 128 of the top panel 120t of the plenum chamber 120 can engage the slots 118 of the top panel 1 lOt of the coil housing 110. A cross-section view along the line 4F-4F is illustrated in Fig. 4F.

As shown in Fig. 4F, the tab 128 can be slid into the slot 118, so that the top panel 120t of the plenum chamber 120 can be easily attached to the top panel 1 lOt of the coil housing 110. After inserting the tab 128 to the slot 1 18, the top panel 120t of the plenum chamber 120 is partially situated on top of the top panel 1 lOt of the coil housing 110. The top panel 120t of the plenum chamber 120 can also be supported by the fan panel 131, with the appreciation that the support provided by the fan panel 131 is not necessary. Referring back to Figs. 1A and IB, the top panel 120t of the plenum chamber 120 can also be supported by the side panels 120a and 120b of the plenum chamber 120.

The use of the slot 118 and the tab 128 can help minimize the use of screws, which can help minimize the labor and/or material costs to assemble the indoor unit 100 and/or reduce material cost. In some embodiments, when the top panel 1 lOt of the coil housing 110 and the top panel 120t of the plenum chamber 120 are relatively long, the engagement of the slot 118 and the tab 128 may not be able to ensure robust attachment. In these embodiments, one or more screws may be used to enhance the attachment between the top panel 1 lOt of the coil housing 1 10 and the top panel 120t of the plenum chamber 120.

The slots 118 and the matching tabs 128 can help simplify installation and/or removal of the plenum chamber 120 from the coil housing 110.

It is appreciated that in some embodiments, the slots can be on the top panel of the plenum chamber and the tabs can be on the top panel of the coil housing.

Referring back to Fig. IB, the filter 122 is mounted to the plenum chamber 120 by one or more retaining pins 123. Figs. 5A to 5F illustrate an embodiment of the retaining pins 123 and a method of using them.

As illustrated in Figs. 5A and 5B, the retaining pins 123 are generally configured to have an "L" shaped profile, which includes a long arm 123a and a short arm 123b. The long arm 123a has a length L5a and the short arm has a length L5b.

The long arm 123a and the short arm 123b are configured to have a first hook 125a and a second hook 125b respectively. The first and second hooks 125a and 125b, as well as the long arm 123a and the short arm 123b are configured to have mounting apertures 127. The mounting apertures can have a diameter D5.

As illustrated in Figs. 5C and 5D, the retaining pin 123 can be configured to

accommodate a relatively thin filter 122a or a relatively thick filter 122b. As shown in Fig. 5C, when a relatively thin filter 122a is used, the first hook 125a of the long arm 123a is configured to catch the side panel 120a of the plenum chamber 120. The short arm 123b is configured to hold the filter 122a in place. As shown in Fig. 5D, when a relatively thick filter 122b is used, the second hook 125b of the short arm 123b is configured to catch the side panel 120a of the plenum chamber 120. The long arm 123a is configured to hold the filter 122b in place. By configuring the retaining pin 123 with two arms of different lengths, the retaining pin 123 can be configured to accommodate filters with different thicknesses. This may help simplify the installation process of the HVAC indoor unit 100.

As illustrated in Figs. 5E and 5F, the first hook 125a or the second hook 125b of the retaining pin 123 is configured to catch a retaining cavity 124 of the side panel 120b of the plenum chamber 120. A pin mounting mechanism 265, such as a self-tapping screw, can be used to fix the retaining pin 123 to the retaining cavity 124.

As illustrated in Fig. 5F, the retaining cavity 124 has a catching aperture 261 that is configured to engage, for example, the pin mounting mechanism 265. The catching aperture 261 of the retaining cavity 124 can have a diameter D6. The diameter D6 can be configured to be relatively smaller than the diameter D5 of the aperture 127 of the retaining pin 123. The diameter D5 is configured so that when the mounting mechanism 265 is positioned in the apertures 127 of the retaining pin 123, the mounting mechanism 265 can rotate freely. The diameter D6 is configured so that the catching aperture 261 of the retaining cavity 124 can catch the mounting mechanism 265.

During installation, when the pin mounting mechanism 265 (such as a self-tapping screw) is used to fix the retaining pin 123 to the retaining cavity 124 by, for example, a rotating motion, the catching aperture 261 of the retaining cavity 124 can catch the pin mounting mechanism 265 (e.g. the stem of a screw), while the retaining pin 123 does not rotate along with the mounting mechanism 265. This can help simplify the installation of the filter 122 by using the retaining pin 123.

It is to be noted that the retaining pin 123 can also be configured to catch cavities located on the top panel 120t and/or the bottom panel 120d of the plenum chamber 120.

The retaining cavity 124 can help quickly position or align the retaining pin 123, so that the aperture 127 of the retaining pin 123 can be align with the catching aperture 261 of the retaining cavity 124 quickly when the hook 125a or 125b catches the retaining cavity 124. The retaining cavity 124 can also provide a recess to accommodate the pin mounting mechanism 265, so that the pin mounting mechanism 265 does not protrude out of the side panel 120b. When an air duct is attached to the side panel 120b (and/or 120a), the recessed pin mounting mechanism 265 does not generally interfere with the installation of the air duct to the side panel 120b (and/or 120a).

With regard to the foregoing description, it is to be understood that changes may be made in detail, without departing from the scope of the present invention. It is intended that the specification and depicted embodiments are to be considered exemplary only, with a true scope and spirit of the invention being indicated by the broad meaning of the claims.

Claims

Claims What is claimed is:

1. A HVAC indoor unit, comprising:

a coil housing, the coil housing includes a fan attachment section and a plenum attachment section;

a fan mounting mechanism; and

a plenum mounting mechanism;

wherein the fan attachment section is separate from the plenum attachment section, the fan attachment section is configured to be attached to a fan panel by the fan mounting mechanism, the plenum attachment section is configured to be attached to a plenum chamber by the plenum mounting mechanism, the fan mounting mechanism is configured to be away from the plenum attachment section, and the plenum mounting mechanism is configured to be away from the fan attachment section.

2. The HVAC indoor unit of claim 1, wherein the fan attachment section is located at a back side of the coil housing.

3. The HVAC indoor unit of claim 1, wherein the plenum attachment section is located at a side of the coil housing.

4. A HVAC indoor unit, comprising:

a coil housing, the coil housing configured to house a heat exchange coil;

the coil housing including a side panel; and

a fan panel;

wherein the side panel has an elongated "L" shaped tail, the "L" shaped tail includes a side attachment section and a back attachment section, the fan panel is attached to the back attachment section, and the side attachment section is configured to receive a side panel of a plenum chamber of the HVAC indoor unit.

5. The HVAC indoor unit of claim 4, wherein the fan panel and the side attachment section of the "L" shaped tail has a space configured to accommodate a mounting mechanism for the panel of a plenum chamber.

6. The HVAC indoor unit of claim 4, further comprising:

a top panel of the coil housing;

wherein a back side of the top panel of the coil housing has one open slot, the open slot is configured to receive a tab of a top panel of a plenum chamber.

7. The HVAC indoor unit of claim 4, further comprising:

a plenum chamber including a side panel; wherein the side panel of the plenum chamber is attached to the side attachment section of the "L" shaped tail of the side panel of the coil housing.

8. The HVAC indoor unit of claim 7, further comprising:

a retaining pin, wherein the retaining pin has a long arm and a short arm, the long arm and the short arm are configured to retain filters with different thicknesses to the plenum chamber.

9. The HVAC indoor unit of claim 8, wherein the long arm includes a first hook and the short arm includes a second hook, the first and second hooks are configured to catch a panel of the plenum chamber.

10. The HVAC indoor unit of claim 8, wherein the long arm and the short arm include a mounting aperture with a first diameter, the panel of the plenum chamber has a catching aperture with a second diameter, and the first diameter is larger than the second diameter.

1 1. A HVAC indoor unit, comprising:

a coil housing, the coil housing configured to house a heat exchange coil assembly; the coil housing including a top panel, wherein a back side of the top panel of the coil housing has one open slot, the open slot is configured to receive a tab of a top panel of a plenum chamber

12. The HVAC indoor unit of claim 1 1, further comprising:

a fan panel; and

a side panel of the coil housing;

wherein the side panel has an elongated "L" shaped tail, the "L" shaped tail includes a side attachment section and a back attachment section,

the fan panel is attached to the back attachment section, and the side attachment section is configured to receive a side panel of a plenum chamber of the HVAC indoor unit.

13. The HVAC indoor unit of claim 12, further comprising:

14. The HVAC indoor unit of claim 13, further comprising:

15. The HVAC indoor unit of claim 14, wherein the long arm includes a first hook and the short arm includes a second hook, the first and second hooks are configured to catch a panel of the plenum chamber.

16. The HVAC indoor unit of claim 14, wherein the long arm and the short arm includes a mounting aperture with a first diameter, the panel of the plenum chamber has a catching aperture with a second diameter, and the first diameter is larger than the second diameter.

17. The HVAC indoor unit of claim 16, wherein the first diameter is configured to allow a mounting mechanism to rotate freely in the mounting aperture, the second diameter is configured to catch the mounting mechanism.

18. A retaining pin for a HVAC indoor unit, comprising:

a long arm; and

a short arm;

wherein the long arm has a first hook and the short arm has a second hook, the first and second hooks are configured to catch a panel of the HVAC indoor unit;

when the first hook is used to catch a panel of the HVAC indoor unit, the short arm is used to retain a filter of a first thickness; and

when the second hook is used to catch a panel of the HVAC indoor unit, the long arm is used to retain a filter of a second thickness.

19. A method of assembling a HVAC indoor unit, comprising:

providing a coil housing, wherein the coil housing is configured to house heat exchange coils;

providing a fan attachment section, wherein the fan attachment section is configured to receive a fan panel of a fan assembly; and

providing a plenum attachment section, wherein the plenum attachment section is configured to receive a plenum chamber;

wherein the plenum attachment section and the fan attachment section are separate from each other.