14½″ Furnace CabinetClick the graphic to enlarge
Made in Colorado · Built for HVAC Professionals
A Better Way to Build the Return Air System.
American-made return air filter boxes and adjustable coil transitions designed for easier installation, cleaner results, and dependable performance.
14½″ · 17½″ · 21″ · 24½″Filter box widths
1″ · 2″ · 4″Filter options
USAManufactured
Air Handler Boxes Available
Featured Product · Return Air Filter Boxes
The Return Air Filter Box Built for the Job.
A purpose-built, galvanized steel return air filter box that helps contractors deliver a clean, professional installation. Available in multiple furnace cabinet widths and filter configurations.
One Product Family. Multiple Configurations.
Designed for common residential HVAC installations, with a practical slide-in filter design and sturdy metal construction.
14½″ width17½″ width21″ width24½″ width17⅝″ height
Verify cabinet dimensions and installation clearance before ordering.
Built for Installers
Practical construction and straightforward filter access for service and replacement.
Filter Flexibility
Configurations for 1-inch, 2-inch, and 4-inch filters.
Wholesale Ready
Ask about contractor and distributor quantities, product availability, and shipping.
Return Air Filter Boxes · Sizing Guide
Find the Right Filter Box for Your Furnace.
Compare our four standard furnace cabinet sizes. Select any graphic to see the full compatibility information and measure your furnace cabinet before ordering.
17½″ Furnace CabinetClick the graphic to enlarge
21″ Furnace CabinetClick the graphic to enlarge
24½″ Furnace CabinetClick the graphic to enlarge
Furnace cabinet width and outside filter box width are different measurements. Verify your actual equipment dimensions before ordering. Brand compatibility depends on the cabinet size, not the brand name alone.
Return Air Filter Boxes · Proven Strength
Built Strong. Tested in the Shop.
See the construction and real-world testing behind our return air filter boxes.
Product Video · Return Air Filter Boxes
See the Return Air Filter Box in Action.
Get a closer look at our return air filter box in this product promotional video.
Installation & Assembly
See How the Return Air Filter Box Goes Together.
Watch our return air filter box assembly video for a walkthrough of the product and its assembly.
Coil Transition Spacers · HVAC Installation
Raise the Coil. Reduce Static Pressure. Improve Airflow.
Give the evaporator coil more room above the furnace. Our adjustable coil transition spacers create a smoother path for airflow while helping installers transition between furnace and coil cabinet sizes.
More Clearance. Better Airflow.
Positioning the coil higher can improve the air path into the evaporator coil and help reduce airflow restriction, depending on the system and installation.
4½″ spacer height6″ spacer heightAdjustable 14″–24″ fit
Built for installers: Adjustable sizing helps accommodate different cabinet combinations without fabricating a one-off transition on every job.
Actual static-pressure improvement depends on equipment, ductwork, and installation. Confirm cabinet dimensions and clearances before ordering.
Raise the Evaporator Coil
Introduce extra space between the furnace and coil for a less restrictive air path.
Help Reduce Static Pressure
Improved transition geometry can reduce resistance where air enters the coil.
Two Height Options
Choose a 4½″ or 6″ spacer for your application.
Product Video · Coil Transitions
See the Coil Transition in Action.
Watch our coil transition promotional video to see how the product is designed to help HVAC installers raise the coil and improve the airflow path.
The Company Behind the Products
Manufactured in Golden, Colorado.
H Manufacturing combines hands-on HVAC industry knowledge with in-house metal fabrication and production capabilities.
Our products are built for the professionals who install and service HVAC systems every day. In addition to our Elevation Air product line, our manufacturing operation supports precision sheet-metal fabrication and production work.
Manufacturing Capabilities
Fiber laser cutting · Sheet metal forming · Production fabrication · Assembly
For custom manufacturing inquiries, contact our team with your drawings and estimated quantities.
Manufacturing InquiryContractors · Distributors · Supply Houses
Let's Talk Products and Pricing.
Tell us which products and sizes you need, along with estimated order quantities. We'll help you take the next step.
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