HVAC Duct

Abstract

An HVAC airflow duct has a polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional Patent Application No. 61/757,033, filed on Jan. 25, 2013 by Richard Lee Jameson, entitled “Foam Duct Panel,” which is incorporated by reference herein as if reproduced in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

BACKGROUND

Some heating, ventilation, and/or air conditioning (HVAC) systems comprise cabinets and/or ducts configured to receive airflow therethrough. In some cases, a component of a cabinet and/or duct may comprise fibrous insulation material, materials comprising heat transfer conductivities that allow condensation formation on the component, and/or extraneous layers of material that, together with foam, are configured to provide a composite component. Some HVAC air handling units and/or are associated with potential sources of fire.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and the advantages thereof, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts.

FIG. 1 is an oblique view of an air handling unit according to embodiments of the disclosure;

FIG. 2 is an orthogonal view of the front of the air handling unit of FIG. 1;

FIG. 3 is a partially exploded oblique view of the air handling unit of FIG. 1;

FIG. 4 is a simplified oblique view of the air handling unit of FIG. 1 showing a plurality of inner shell components encased within outer skins;

FIG. 5 is an oblique left side view of the heat exchanger cabinet right shell of FIG. 1;

FIG. 6 is an oblique left side view of the blower cabinet right shell of FIG. 1;

FIG. 7 is an oblique front view of a panel of the air handling unit of FIG. 1;

FIG. 8 is an oblique rear view of a panel of the air handling unit of FIG. 1;

FIG. 9 is an oblique front view of an alternative embodiment of a panel;

FIG. 10 is an orthogonal rear view of the panel of FIG. 9;

FIG. 11 is an oblique front cut-away view of a gas furnace according to embodiments of the disclosure;

FIG. 12 is a schematic view of a structure associated with an HVAC system according to an embodiment of the disclosure;

FIG. 13 is an orthogonal side view of a panel comprising an attached hook;

FIG. 14 is an orthogonal side view of a panel comprising a hook that is integral with a skin of the panel; and

FIG. 15 is an orthogonal side view of a panel with an integral hook.

DETAILED DESCRIPTION

This disclosure provides, in some embodiments, systems and methods for (1) forming an HVAC air handling unit, an HVAC cabinet, and/or an HVAC duct comprising a substantially polyetherimide based foam, (2) providing a relatively high heat resistant, highly insulative, and/or structurally rigid HVAC air handling unit, HVAC cabinet, and/or HVAC duct comprising a polyetherimide based foam, and (3) sealing an HVAC air handling unit, an HVAC cabinet, and/or an HVAC duct using a panel comprising a polyetherimide based foam. In some embodiments, an inner wall of an HVAC air handling unit, an HVAC cabinet, and/or an HVAC duct that may be exposed to an airflow may comprise a foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide.

Referring now to FIGS. 1-3, an air handling unit (AHU) 100 according to the disclosure is shown. In this embodiment, AHU 100 comprises a lower blower cabinet 102 attached to an upper heat exchanger cabinet 104. Most generally and for purposes of this discussion, AHU 100 may be described as comprising a top side 106, a bottom side 108, a front side 110, a back side 112, a left side 114, and a right side 116. Such directional descriptions are meant to assist the reader in understanding the physical orientation of the various components parts of the AHU 100 but that such directional descriptions shall not be interpreted as limitations to the possible installation orientations of an AHU 100. Further, the above-listed directional descriptions may be shown and/or labeled in the figures by attachment to various component parts of the AHU 100. Attachment of directional descriptions at different locations or two different components of AHU 100 shall not be interpreted as indicating absolute locations of directional limits of the AHU 100, but rather, that a plurality of shown and/or labeled directional descriptions in a single Figure shall provide general directional orientation to the reader so that directionality may be easily followed amongst various the figures. Still further, the component parts and/or assemblies of the AHU 100 may be described below as generally having top, bottom, front, back, left, and right sides which should be understood as being consistent in orientation with the top side 106, bottom side 108, front side 110, back side 112, left side 114, and right side 116 of the AHU 100.

Blower cabinet 102 comprises a four-walled fluid duct that accepts fluid (air) in through an open bottom side of the blower cabinet 102 and allows exit of fluid through an open top side of the blower cabinet 102. In this embodiment, the exterior of the blower cabinet 102 comprises a blower cabinet outer skin 118 and a blower cabinet panel 120. The blower cabinet panel 120 is removable from the remainder of the blower cabinet 102 thereby allowing access to an interior of the blower cabinet 102. Similarly, heat exchanger cabinet 104 comprises a four-walled fluid duct that accepts fluid (air) from the blower cabinet 102 and passes the fluid from an open bottom side of the heat exchanger cabinet 104 and allows exit of the fluid through an open top side of the heat exchanger cabinet 104. In this embodiment, the exterior of the heat exchanger cabinet 104 comprises a heat exchanger cabinet outer skin 122 and a heat exchanger cabinet panel 124. The heat exchanger cabinet panel 124 is removable from the remainder of the heat exchanger cabinet 104 thereby allowing access to an interior of the heat exchanger cabinet 104.

The AHU 100 further comprises a plurality of selectively removable components. More specifically, the AHU 100 comprises a heater assembly 126 and may be removably carried within the heat exchanger cabinet 104. The AHU 100 further comprises a refrigeration coil assembly 128 that may also be removably carried within the heat exchanger cabinet 104. In this embodiment, the heater assembly 126 is configured to be optionally carried within heat exchanger cabinet 104 nearer the top side 106 of the AHU 100 than the refrigeration coil assembly 128. Similarly, the AHU 100 comprises a blower assembly 130 that may be removably carried within the blower cabinet 102. The AHU 100 may be considered fully assembled when the blower assembly 130 is carried within the blower cabinet 102, each of the refrigeration coil assembly 128 and the heater assembly 126 are carried within the heat exchanger cabinet 104, and when the blower cabinet panel 120 and heat exchanger cabinet panel 124 are suitably associated with the blower cabinet outer skin 118 and the heat exchanger cabinet outer skin 122, respectively. When the AHU 100 is fully assembled, fluid (air) may generally follow a path through the AHU 100 along which the fluid enters through the bottom side 108 of the AHU 100, successively encounters the blower assembly 130, the refrigeration coil assembly 128, and the heater assembly 126, and thereafter exits the AHU 100 through the top side 106 of the AHU 100.

In this embodiment, each of the four walls of the blower cabinet 102 and the heat exchanger cabinet 104 are configured to have a double-wall construction. More specifically, the heat exchanger cabinet 104 further comprises a heat exchanger cabinet right shell 132 and a heat exchanger cabinet left shell 134. In this embodiment, the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may be joined to generally form the interior of the heat exchanger cabinet 104. In order to form the above-mentioned double-wall construction for the heat exchanger cabinet 104, the heat exchanger cabinet outer skin 122 generally covers the right side and back side of the heat exchanger cabinet right shell 132 while also generally covering the left side and back side of the heat exchanger cabinet left shell 134. Most generally, the heat exchanger cabinet right shell 132, the heat exchanger cabinet left shell 134, and the heat exchanger cabinet outer skin 122 are shaped so that upon their assembly together a heat exchanger cabinet wall space exists between the heat exchanger cabinet outer skin 122 and each of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134. The blower cabinet right shell 136, the blower cabinet left shell 138, and the blower cabinet outer skin 118 are also shaped so that upon their assembly together a blower cabinet wall space exists between the blower cabinet outer skin 118 and each of the blower cabinet right shell 136 and the blower cabinet left shell 138.

In some embodiments, one or more of the heat exchanger cabinet wall space and blower cabinet wall space may be at least partially filled with a foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide. At least partially filling one or more of the spaces may increase a structural integrity of the AHU 100, may increase a thermal resistance of the AHU 100 between the interior of the AHU 100 and the exterior of the AHU 100, may decrease air leakage from the AHU 100, and may reduce and/or eliminate the introduction of volatile organic compounds (VOCs) into breathing air attributable to the AHU 100. Such a reduction in VOC emission by the AHU 100 may be attributable to the lack of and/or reduced use of traditional fiberglass insulation within the AHU 100 made possible by the insulative properties provided by the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, that may be disposed within the spaces.

In some embodiments, each of the blower cabinet outer skin 118 and the heat exchanger cabinet outer skin 122 may be constructed of metal and/or plastic. Each of the heat exchanger cabinet right shell 132, the heat exchanger cabinet left shell 134, blower cabinet right shell 136, and blower cabinet left shell 138 may be constructed of a sheet molding compound (SMC). The SMC may be chosen for its ability to meet the primary requirements of equipment and/or safety certification organizations and/or its relatively rigid cleanable surfaces that are resistant to mold growth and compatible with the use of antimicrobial cleaners. In some embodiments, polyurethane foam may be used to fill the spaces and the polyurethane foam may comprise refrigerant and/or pentane to enhance the thermal insulating characteristics of the foam. Of course, in alternative embodiments, any other suitable material may be used to form the components of the AHU 100. In still other embodiments, the above-described shells and skins may comprise the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide. Further, the shells and/or skins may be formed integrally with the above-described the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, that fills the above-described spaces so that the shell/skin/space combinations may each comprise substantially unitary components of substantially homogenous material construction. It will be appreciated that the panel 124 may be constructed in any of the above-described manners and particularly may comprise the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide.

Further, each of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 comprise an interior side surface 146, an interior rear surface 148, an exterior side surface, and an exterior rear surface. Similarly, each of the blower cabinet right shell 136 and the blower cabinet left shell 138 comprise an interior side surface 154, an interior rear surface 156, an exterior side surface, and an exterior rear surface. Most generally, and with a few exceptions, each of the pairs of interior side surfaces 146, interior rear surfaces 148, exterior side surfaces, exterior rear surfaces, interior side surfaces 154, interior rear surfaces 156, exterior side surfaces, and exterior rear surfaces are substantially mirror images of each other. More specifically, the above listed pairs of surfaces are substantially mirror images of each other about a bisection plane 162 (see FIG. 2) that is generally parallel to both the AHU left side 114 and the AHU right side 116 and which is substantially equidistant from both the AHU left side 114 and the AHU right side 116.

Referring now to FIGS. 4 and 5, simplified views of the AHU 100 are provided. Each of the heat exchanger cabinet right shell 132, the heat exchanger cabinet left shell 134, the blower cabinet right shell 136, and the blower cabinet left shell 138 comprise integral features for carrying removable components of the AHU 100. More specifically, the interior side surfaces 146 and interior rear surfaces 148 of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 comprise heater assembly mounting channels 200 bound above and below by heater assembly rails 202. The heater assembly rails 202 protrude inwardly from the remainder of the respective interior side surfaces 146 and interior rear surfaces 148 so that complementary shaped structures of the heater assembly 126 may be received within the channels 200 and retained within the channels 200 by the heater assembly rails 202. In this embodiment, the heater assembly 126 may be selectively inserted into the heat exchanger cabinet 104 by aligning the heater assembly 126 properly with the heater assembly mounting channels 200 and sliding the heater assembly 126 toward the AHU back side 112. Of course, the heater assembly 126 may be selectively removed from the heat exchanger cabinet 104 by sliding the heater assembly 126 away from the AHU back side 112. Further, one or more of the interior side surfaces 146 may comprise a heater assembly shelf 204 to slidingly receive a portion of the heater assembly 126 during insertion of the heater assembly 126 until the heater assembly 126 abuts a shelf back wall 206.

Still referring to FIGS. 4 and 5, the interior side surfaces 146 of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 comprise refrigeration coil assembly mounting channels 208 bound above and below by refrigeration coil assembly rails 210. The refrigeration coil assembly rails 210 protrude inwardly from the remainder of the respective interior side surfaces 146 so that complementary shaped structures of the refrigeration coil assembly 128 may be received within the channels 208 and retained within the channels 208 by the refrigeration coil assembly rails 210. In this embodiment, the refrigeration coil assembly 128 may be selectively inserted into the heat exchanger cabinet 104 by aligning the refrigeration coil assembly 128 properly with the refrigeration coil assembly mounting channels 208 and sliding the refrigeration coil assembly 128 toward the AHU back side 112. Of course, the refrigeration coil assembly 128 may be selectively removed from the heat exchanger cabinet 104 by sliding the refrigeration coil assembly 128 away from the AHU back side 112.

It will further be appreciated that one or more of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may comprise integrally formed electrical conduit apertures 212 which form openings between the interior of the heat exchanger cabinet 104 and the heat exchanger cabinet wall space. The electrical conduit apertures 212 are formed and/or shaped to closely conform to the shape of electrical lines and/or electrical conduit that may be passed through the electrical conduit apertures 212. However, in some embodiments, stabilizer pads 214 may be integrally formed about the circumference of the electrical conduit apertures 212 so that the electrical lines and/or electrical conduit may be more tightly held, isolated from the general cylindrical surface of the electrical conduit apertures 212, and/or to reduce friction of insertion of electrical lines and/or electrical conduit while retaining a tight fit between the stabilizer pads 214 and the electrical lines and/or electrical conduit. Further, the stabilizer pads 214 may be configured to interact with nuts of electrical conduit connectors so that the stabilizer pads 214 serve to restrict rotational movement of such nuts. By restricting such rotational movement of nuts, the stabilizer pads 214 may provide easier assembly and/or disassembly of the electrical conduit and related connectors to the heat exchanger cabinet 104. The electrical conduit apertures 212 are not simply holes formed in the interior side surfaces 146, but rather, are substantially tubular protrusions extending outward from the exterior side surfaces.

It will further be appreciated that one or more of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may comprise drain pan indentions 216. More specifically, the heat exchanger interior side surfaces 146 may generally comprise a sloped portion 218 sloped from a bottom side to the drain pan indentions 216 so that the bottom of the interior side surfaces 146 protrude further inward and the remainder of the sloped portion 218. The drain pan indentions 216 may form a concavity open toward the interior of the heat exchanger cabinet 104. The interior side surfaces 146 further comprises a front boundary wall 220 with integral drain tubes 222 extending into the concavity formed by the drain pan indentions 216. In some embodiments, the AHU 100 may be installed and/or operated in an installation orientation where the drain pan indention 216 of an interior side surface 146 is located below the refrigeration coil assembly 128 and so that fluids may, with the assistance of gravity, aggregate within the concavity of the drain pan indention 216 and thereafter exit the AHU 100 through the integral drain tubes 222. More specifically, the sloped portion 218 may direct fluids falling from the refrigeration coil assembly 128 toward the concavity formed by a drain pan indention 216. In this manner, the integrally formed slope portion 218, the drain pan indentions 216, and the front boundary wall 220 may serve as a condensation drain pan for the AHU 100 and may prevent the need to install a separate drain pan and/or to rearrange the configuration of a separate drain pan based on a chosen installation orientation for the AHU 100. Further, when in use, a drain pan indention 216 and sloped portion 218 may cooperate with airflow generated by blower assembly 130 to direct condensation to the integral drain tubes 222.

It will further be appreciated that one or more of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may comprise integral assembly recesses 224. Assembly recesses 224 may be located near a lower end of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134. Assembly recesses 224 may accept mounting hardware therein for joining the heat exchanger cabinet 104 to the blower cabinet 102. In this embodiment, the recesses 224 are substantially shaped as box shaped recesses, however, in alternative embodiments, the recesses 224 may be shaped any other suitable manner. Additionally, one or more of the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may comprise integral fastener retainer protrusions 226. Fastener retainer protrusions 226 may be used to hold threaded nuts or other fasteners. Further, in other embodiments, retainer protrusions 226 may themselves be threaded or otherwise configured to selectively retaining fasteners inserted therein. Still further, the heat exchanger cabinet right shell 132 and the heat exchanger cabinet left shell 134 may comprise support bar slots 228 configured to receive the opposing ends of a selectively removable structural crossbar.

Referring now to FIGS. 4 and 6, one or more of the blower cabinet right shell 136 and the blower cabinet left shell 138 may comprise blower assembly mounting channels 230 bound above and below by blower assembly rails 232. The blower assembly rails 232 protrude inwardly from the remainder of the respective interior side surfaces 154 so that complementary shaped structures of the blower assembly 130 may be received within the channels 230 and retained within the channels 230 by the blower assembly rails 232. In this embodiment, the blower assembly 130 may be selectively inserted into the blower cabinet 102 by aligning the blower assembly 130 properly with the blower assembly mounting channels 230 and sliding the blower assembly 130 toward the AHU back side 112. Of course, the blower assembly 130 may be selectively removed from the blower cabinet 102 by sliding the blower assembly 130 away from the AHU back side 112.

It will further be appreciated that one or more of the blower cabinet right shell 136 and the blower cabinet left shell 138 may comprise filter mounting channels 234 bound above and below by filter rails 236. The filter rails 236 protrude inwardly from the remainder of the respective interior side surfaces 154 so that complementary shaped structures of a filter may be received within the channels 234 and retained within the channels 234 by the filter rails 236. In this embodiment, a filter may be selectively inserted into the blower cabinet 102 by aligning the filter properly with the filter mounting channels 234 and sliding the filter toward the AHU back side 112. Of course, the filter may be selectively removed from the blower cabinet 102 by sliding the filter away from the AHU back side 112. In some embodiments, the filter mounting channel 234 may be sloped downward from the front to the back of the AHU 100. Further, in some embodiments, one or more of the filter rails 236 may comprise filter protrusions 238 which may serve to more tightly hold a filter inserted into the filter mounting channels 234. In some embodiments, one or more of the blower cabinet right shell 136 and the blower cabinet left shell 138 may comprise fastener retainer protrusions 226. Still further, one or more of the blower cabinet right shell 136 and the blower cabinet left shell 138 may comprise integral assembly recesses 240. Assembly recesses 240 may be located near an upper end of the blower cabinet right shell 136 and the blower cabinet left shell 138. Assembly recesses 240 may accept mounting hardware therein for joining the blower cabinet 102 to the heat exchanger cabinet 104. In this embodiment, the recesses 240 are substantially shaped as box shaped recesses, however, in alternative embodiments, the recesses 240 may be shaped in any other suitable manner.

Referring now to FIGS. 7 and 8, oblique front and rear views of panel 124 are shown, respectively. In this embodiment, the outer skin 125 may comprise the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, while a concavity of the outer skin 125 that is generally open toward a rear direction may be at least partially filled the foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, to form a structural and/or insulative and/or fire/smoke resistant structure 127 that is generally represented in FIG. 8 by dashed lines along at least the most rearward edges of the structure 127. In some cases, the outer skin 125 and the structure 127 may be integrally formed so that the panel 124 comprises a substantially unitary construction.

While many of the features of the heat exchanger cabinet right shell 132, heat exchanger cabinet left shell 134, blower cabinet right shell 136, blower cabinet left shell 138, and/or panels 120,124 may be formed integrally to those respective components in a single molding and/or injection process. However in alternative embodiments, the various integral features may be provided through a series of moldings, and/or injections, thermal welding, gluing, or any other suitable means of assembling a singular structure comprising the various features as is well known to those skilled in the art. Further, one or more of the components disclosed herein as being formed integrally, in some embodiments, may be formed from multiple components coupled together.

Referring now to FIGS. 9 and 10, an oblique front and an orthogonal rear view of an alternative embodiment of a panel 300 are shown, respectively. The panel 300 is substantially similar to panel 124 but differs in that the panel is integrally formed of foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains an insulation value R Value of about 4.2 or greater, such as, but not limited to, polyetherimide. In this embodiment, the panel 300 further comprises a gasket 302 that extends along a perimeter of the rear wall of the panel 300. In some cases, the panel 300 may be utilized to seal an AHU such as AHU 100 and/or any other HVAC cabinet and/or duct configured to pass air therethrough.

While many of the features of the heat exchanger cabinet right shell 132, heat exchanger cabinet left shell 134, blower cabinet right shell 136, blower cabinet left shell 138, and/or panels 120,124 may be formed integrally to those respective components in a single molding and/or injection process. However in alternative embodiments, the various integral features may be provided through a series of moldings, and/or injections, thermal welding, gluing, or any other suitable means of assembling a singular structure comprising the various features as is well known to those skilled in the art. Further, one or more of the components disclosed herein as being formed integrally, in some embodiments, may be formed from multiple components coupled together.

Referring now to FIG. 11, an oblique front cut-away view of a furnace according to an embodiment of the disclosure is shown. Furnace 400 comprises a modulating combustion system 414. It will be appreciated that the term, “modulating,” as used in this disclosure is meant to indicate that a system or device may be selectively operated at substantially any value over a range of performance values in a manner consistent with a control resolution of the system. Generally, the furnace 400 is operable so that the furnace 400 may selectively perform at substantially any selected output capacity value (kBtu/Hr) ranging from a maximum output capacity (100% output capacity) to a minimum output capacity (e.g., in some embodiments, about 40% of the maximum output capacity) with the modulating combustion system 414 capable of being constantly operated over a range of output capacities. The modulating combustion system 414 is housed within the cabinet 412 and comprises a burner assembly 416, a modulating gas valve assembly 418, and a control assembly 420. The furnace 400 further comprises a heat exchanger assembly 422 which comprises a plurality of heat exchangers 424, a variable speed induced draft blower 426, and a variable speed circulating air blower 428. It will be appreciated that the furnace 400 further comprises a combustion intake space 430 that surrounds the exterior of the draft blower 426 and the exterior of the heat exchangers 424. When the draft blower 426 draft is operated, air is drawn from the intake space 430 and is passed through the heat exchangers 424 and into a header 434 that accepts exhaust from the heat exchangers 424 and provides a flow path for the exhaust to reach the draft blower 426. It will be appreciated that during operation of the furnace 400, the local pressure within the intake space 430 may be different from the local pressure within the header 434. In this embodiment, any of the components of the cabinet 412 and/or the exhaust 432 may comprise foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide. In some cases, the furnace 400 may comprise a panel substantially similar to panel 124 and/or panel 300.

Referring now to FIG. 12, a simplified schematic diagram of the air circulation paths for a structure 500 conditioned by two HVAC systems 501 is shown. In this embodiment, the structure 500 is conceptualized as comprising a lower floor 502 and an upper floor 504. The lower floor 502 comprises zones 506, 508, and 510 while the upper floor 504 comprises zones 512, 514, and 516. The HVAC system 501 associated with the lower floor 502 is configured to circulate and/or condition air of lower zones 506, 508, and 510 while the HVAC system 501 associated with the upper floor 504 is configured to circulate and/or condition air of upper zones 512, 514, and 516. In addition to the components of HVAC system 501 described above, in this embodiment, each HVAC system 501 further comprises a ventilator, a prefilter, a humidifier, and a bypass duct. The ventilator may be operated to selectively exhaust circulating air to the environment and/or introduce environmental air into the circulating air. The prefilter may generally comprise a filter media selected to catch and/or retain relatively large particulate matter prior to air exiting the prefilter and entering the air cleaner. The humidifier may be operated to adjust a humidity of the circulating air. The bypass duct may be utilized to regulate air pressures within the ducts that form the circulating air flow paths. In some embodiments, air flow through the bypass duct may be regulated by a bypass damper while air flow delivered to the zones 506, 508, 510, 512, 514, and 516 may be regulated by zone dampers. Still further, each HVAC system 501 may further comprise a zone thermostat and a zone sensor. In some embodiments, a zone thermostat may communicate with the system controller and may allow a user to control a temperature, humidity, and/or other environmental setting for the zone in which the zone thermostat is located. Further, the zone thermostat may communicate with the system controller to provide temperature, humidity, and/or other environmental feedback regarding the zone in which the zone thermostat is located. In some embodiments, a zone sensor may communicate with the system controller to provide temperature, humidity, and/or other environmental feedback regarding the zone in which the zone sensor is located. While HVAC systems 501 are shown as a so-called split system comprising an indoor unit located separately from the outdoor unit, alternative embodiments of an HVAC system 501 may comprise a so-called package system in which one or more of the components of the indoor unit and one or more of the components of the outdoor unit are carried together in a common housing or package. The HVAC system 501 is shown as a so-called ducted system where the indoor unit is located remote from the conditioned zones, thereby requiring air ducts to route the circulating air. However, in alternative embodiments, an HVAC system 501 may be configured as a non-ducted system in which the indoor unit and/or multiple indoor units associated with an outdoor unit is located substantially in the space and/or zone to be conditioned by the respective indoor units, thereby not requiring air ducts to route the air conditioned by the indoor units. Still referring to FIG. 12, the system controllers may be configured for bidirectional communication with each other and may further be configured so that a user may, using any of the system controllers, monitor and/or control any of the HVAC system 501 components regardless of which zones the components may be associated. Further, each system controller, each zone thermostat, and each zone sensor may comprise a humidity sensor. As such, it will be appreciated that structure 500 is equipped with a plurality of humidity sensors in a plurality of different locations. In some embodiments, a user may effectively select which of the plurality of humidity sensors is used to control operation of one or more of the HVAC systems 501. This disclosure contemplates that any of the components of FIG. 12 that receive airflow therethrough, whether a duct, cabinet, and/or any other type of air delivery pipe, tube, and/or passage, may comprise foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide.

FIGS. 13-15 are orthogonal side views of panels comprising hooks. The panel 600 of FIG. 13 comprises a hook 602 that is mechanically attached to the remainder of the panel 600 via an adhesive and/or a fastener. The panel 700 of FIG. 14 comprises a hook 702 that is integrally formed with a skin 704 of the panel 700. The panel 800 of FIG. 15 comprises a hook 802 that is integrally formed with the remainder of the panel 800. Any of the portions and/or components of the panels 600, 700, 800 may comprise foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide.

In some embodiments, panels and/or AHU components constructed of foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may provide acceptable flatness, rigidity, and/or insulative properties to prevent condensation while also resisting burning and/or charring of the components. In some cases, the panels and/or AHU components may, without substantial further processing provide acceptable aesthetic qualities, such as a desirable smoothness and/or glossiness.

In some cases, panels and/or AHU components constructed of foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may be constructed by die cutting the material to complement skin shapes and then vacuum forming or pressure forming plastic skin sheets on as many as five sides of the die cut material followed by cutting the skinned sheet out in line of a thermoform machine. The thermoform machine may receive generally rectangular shapes and then punch out shapes and holes after thermoforming. Sheets may be extruded to match colors and cut to meet shape requirements. In some embodiments, some components may be die cut and thereafter pressure-formed to produce contoured surfaces. In some cases, sheets and/or skins may be coextruded with components formed of foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, so that dissimilar materials are simultaneously extruded. Foamed components may be joined to other components by vertically dropping like a parison and/or by gluing the foamed components to the other components. The components comprising foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may be caste into shapes, coextruded with reinforcements, and/or provided aesthetically pleasing skinned surfaces using heat, pressure, and/or chemicals. In some cases, injection molding, two shot molding for foam portions and skin portions, and insert molding the foam portions are contemplated.

In some cases, panels, doors, and/or other removable barriers comprising foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may be attached to other components by sandwiching a bracket between thermoformed skin and the foam, mechanically and/or chemically fastening the foam to the other component, using screws and/or other fasteners to join the component to other components, using magnetic strips, gluing and/or adhesion mounting, providing the component with a feature complementary to a feature of the other component to which it is joined, and/or by packing or subsequently sealing the barriers to the other components. Panels, doors, and/or other removable barriers comprising foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may be provided with seals using exiting seal bead equipment, forming flush mounting surfaces in the components, using a peel and stick gasket material, using rib or other types of features to create hard seals on recesses of the components, using wiper style gasket material to seal in a frame so that internal pressures assist in maintaining the seal, using extruded rubber tubes seals such as those used in automotive applications, and/or the like. Seal attachments may be accomplished by utilizing insert mold seals, coextruding the seals with other components, gluing the seals to the panels, doors, and/or other removable barriers, using adhesive tape to attach the seals, ultrasonically welding the seals in place, heat staking the seals in place, and/or otherwise mechanically fastening the seals in place. It will further be appreciated that this disclosure contemplates retrofitting exiting cabinets that initially comprise foil faced fiberglass with panels, doors, and/or other removable barriers comprising foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide. In some cases, components comprising foamed and/or unfoamed polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value for a given application, in some cases, an R Value of about 4.2 or greater, such as, but not limited to, polyetherimide, may be pressure formed onto a side of a preexisting wall that is exposed to airflow so that HVAC system noise is reduced.

At least one embodiment is disclosed and variations, combinations, and/or modifications of the embodiment(s) and/or features of the embodiment(s) made by a person having ordinary skill in the art are within the scope of the disclosure. Alternative embodiments that result from combining, integrating, and/or omitting features of the embodiment(s) are also within the scope of the disclosure. Where numerical ranges or limitations are expressly stated, such express ranges or limitations should be understood to include iterative ranges or limitations of like magnitude falling within the expressly stated ranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4, etc.; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). For example, whenever a numerical range with a lower limit, Rl, and an upper limit, Ru, is disclosed, any number falling within the range is specifically disclosed. In particular, the following numbers within the range are specifically disclosed: R=Rl+k*(Ru−Rl), wherein k is a variable ranging from 1 percent to 100 percent with a 1 percent increment, i.e., k is 1 percent, 2 percent, 3 percent, 4 percent, 5 percent, . . . 50 percent, 51 percent, 52 percent, . . . , 95 percent, 96 percent, 97 percent, 98 percent, 99 percent, or 100 percent. Moreover, any numerical range defined by two R numbers as defined in the above is also specifically disclosed. Use of the term “optionally” with respect to any element of a claim means that the element is required, or alternatively, the element is not required, both alternatives being within the scope of the claim. Use of broader terms such as comprises, includes, and having should be understood to provide support for narrower terms such as consisting of, consisting essentially of, and comprised substantially of. Accordingly, the scope of protection is not limited by the description set out above but is defined by the claims that follow, that scope including all equivalents of the subject matter of the claims. Each and every claim is incorporated as further disclosure into the specification and the claims are embodiment(s) of the present invention.

Claims

1. An HVAC airflow duct, comprising:

a polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value.

2. The HVAC airflow duct of claim 1, wherein the polymeric material is a foamed material.

3. The HVAC airflow duct of claim 1, wherein the polymeric material is an unfoamed material.

4. The HVAC airflow duct of claim 1, wherein the polymeric material comprises polyetherimide.

5. The HVAC airflow duct of claim 1, wherein the duct comprises a removable panel.

6. The HVAC airflow duct of claim 5, wherein the removable panel comprises the polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value.

7. The HVAC airflow duct of claim 5, wherein the removable panel comprises polyetherimide.

8. The HVAC airflow duct of claim 7, wherein the polyetherimide is foamed.

9. The HVAC airflow duct of claim 7, wherein the polyetherimide is unfoamed.

10. The HVAC airflow duct of claim 7, wherein the panel comprises a hook.

11. The HVAC airflow duct of claim 10, wherein the hook comprises polyetherimide.

12. The HVAC airflow duct of claim 11, wherein the hook is integrally formed with the remainder of the panel.

13. An HVAC cabinet, comprising:

an airflow passage at least partially defined by a component comprising a polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or and/or maintains or exceeds a minimum insulation value.

14. The HVAC cabinet of claim 13, wherein the component is a composite component comprising a skin joined to the component.

15. The HVAC cabinet of claim 13, wherein the component is a removable panel.

16. The HVAC cabinet of claim 15, further comprising:

a seal carried by the removable panel.

17. The HVAC cabinet of claim 15, further comprising:

a panel mounting feature carried by the removable panel.

18. The HVAC cabinet of claim 17, wherein the panel mounting feature comprises a hook.

19. The HVAC cabinet of claim 17, wherein the panel mounting feature comprises the polymeric material that meets UL723 and/or ASTM E84 of at least 25/50 or better and/or maintains or exceeds a minimum insulation value.

20. The HVAC cabinet of claim 13, wherein the cabinet further comprises at least one of a furnace cabinet and an evaporator cabinet.