Patent Application
20100112930
The subject invention generally pertains to refrigerant air handling systems and more specifically to a roof assembly for such a system.
Air handlers or the air handler section of an air conditioning unit for meeting the HVAC (heating, ventilating and air conditioning) needs of a building often comprise a refrigerant or other fluid based system housed within a sheet metal enclosure. The refrigerant system may include one or more compressors, a condenser, an evaporator, fans, filters, dampers, and various other equipment. When serving a large commercial, institutional or industrial building, it is not unusual for an air handler to have an enclosure that is over thirty feet long, twelve feet wide, and eight feet tall.
Such large enclosures can be difficult to assemble in the factory. Installing the massive roof in proper alignment with all the various components inside the enclosure can be particularly challenging, time consuming and potentially hazardous. Fitting the roof to the components underneath it usually involves the use of relatively large, cumbersome fixtures, braces, lifting devices, and multiple workers to assure alignment and fit up. Due to the height of the enclosure, it is also difficult to ergonomically secure the internal components in place and assure proper sealing.
Consequently, there is a need for large air handler enclosures that are quicker, easier and safer to assemble.
It is an object of the invention to provide an enclosure for an air handler with alignment features that help guide an entire roof onto various components underneath the roof.
Another object of some embodiments is to provide alignment features that help align the roof in two dimensions, lengthwise and widthwise.
Another object of some embodiments is to incorporate a tapered lead-in edge in the upper corners of a block-off for an evaporator, filter rack, damper, fan and/or other HVAC equipment so that the lead-in edge engages a roof rail to help align the roof in a widthwise direction.
Another object of some embodiments is to fasten cross rails to the underside of the roof, wherein the cross rails include an inclined lead-in flange that engages the upper edge of various internal HVAC equipment, thus helping align the roof in a lengthwise direction.
Another object of some embodiments is to install a gasket that not only provides sealing between the underside of the roof and the upper surface of a block-off but also helps fill a generally triangular gap created by the tapered lead-in edge of the block-off.
Another object of some embodiments is to provide lateral structural support for internal components, wherein the cross rails include a vertical flange that mates to various internal components thus reducing the need for mechanical fasteners.
Another object of some embodiments is to provide some vertical clearance between an upper surface of an internal panel and the underside of a roof, thereby providing some vertical “float” between the internal panel and the roof.
One or more of these and/or other objects of the invention are provided by an air handler comprising an enclosure that contains various HVAC components and bi-directional alignment features. During factory assembly, the alignment features help align the enclosure roof to the components in both lengthwise and widthwise directions.
For the illustrated example, air handler 12 comprises one or more compressors 14 for providing compressed refrigerant, a condenser coil heat exchanger 16 for condensing the compressed refrigerant from compressors 14, one or more fans 18 for cooling condenser 16, an evaporator coil heat exchanger 20 (or some other type of heat exchanger containing a fluid) for providing a cooling effect caused by refrigerant expanding as a flow restriction (not shown) conveys the fluid from condenser 16 to evaporator 20, a supply fan 22 that forces air through evaporator 20 to produce cool air that can be supplied to a comfort zone via a supply air outlet 24, a filter rack 26 holding one or more elements for filtering air prior to passing through evaporator 20, a fresh air inlet 28 for receiving outdoor air, a return air inlet 30 for receiving return air from the comfort zone, a damper 32 for creating a certain mixture of return air and outdoor air, and an exhaust fan 34 for discharging a portion of return air.
Many of the aforementioned components of air handler 12 are housed within an enclosure 36 comprising a base 38, a plurality of side panels 40, an end wall 42, a bulkhead wall 44, and a roof 46. Enclosure 36 has an overall length 48, a width 50 (
Since the active area of some or all of the air handler's internal components might not extend the full width or height of enclosure 36, to prevent airflow from bypassing those components, an internal panel or block-off can be added along the outer periphery of the components. For the illustrated example, evaporator 20 includes block-off extension 20′, damper 32 includes block-off extension 32′, filter rack 26 includes block-off extension 26′, and fan 22 includes block-off extension 22′ (also known as a fan board). In some cases, an internal panel or block-off can simply serve as a standalone divider in an enclosure and not necessarily be connected to any active component.
It would not be unusual for an air handler to be thirty feet long, twelve feet wide, and eight feet tall. A unit of such size can be difficult to assemble. Installing the roof in proper alignment with all the various internal HVAC components can be particularly challenging. To address this problem, air handler 12 includes two alignment features that ensure the assembly is properly aligned along both the length 48 and width 50 of enclosure 36.
To align the internal components to roof 46 along length 48, a plurality of cross rails 54 are attached to the underside of roof 46. Cross rails 54 are elongate along the width 50 of air handler 12 but do not necessarily extend the full width. Cross rails 54 are shown running perpendicular to length 48; however, rails 54 could also lie at some other angle. Each rail 54 includes a lead-in flange 56 that lies at an incline to help guide roof 46 onto a component. Referring to
To assist alignment in a direction parallel to width 50, each internal panel or block-off includes a pair of upper corners that are beveled to help guide a roof rail 62 of roof 46 into position. In
Although the invention is described with respect to a preferred embodiment, modifications thereto will be apparent to those of ordinary skill in the art. The scope of the invention, therefore, is to be determined by reference to the following claims:
