Recommended Filter Rack Dimensions
For a 60,000 BTU upflow gas furnace, the minimum recommended filter rack dimensions are typically as follows:
| Dimension | Recommended Size |
|---|---|
| Width and Height | 16 inches x 25 inches (or equivalent area) |
| Depth | 1 inch |
The recommended width and height of 16 inches x 25 inches (or equivalent area) ensures sufficient airflow and filter area for a 60,000 BTU upflow gas furnace. The standard depth of 1 inch is suitable for most residential air filters.
How to Determine the Correct Filter Rack Size?
1. Consult the Furnace Manual
The best starting point is to refer to the specific furnace model’s manual, which usually provides recommended filter sizes and configurations.
2. Measure the Existing Filter Area
Measure the space available for the filter rack to ensure it fits without obstructing airflow. Consider the dimensions of the furnace and any surrounding obstructions.
3. Calculate Airflow Requirements
Ensure the filter rack does not restrict airflow. For example, a 60,000 BTU furnace might require about 400 CFM per ton when cooling, and the filter rack should not reduce this airflow significantly.
What Customizations are Available for Confined Spaces?
1. Transition and Duct Modifications
If there is limited space to the left or right of the furnace, you may need to create a transition to move the return air intake. This could involve custom ductwork to redirect airflow.
2. Custom Filter Racks
In tight spaces, custom filter racks might be necessary. This could include raising the furnace using a custom box to allow for bottom return air intake or using right-angle air filter configurations.
3. Riser Boxes and Stacked Media Cabinets
For larger systems or confined spaces, riser boxes and stacked media cabinets can be used to increase filter area without obstructing airflow.
Tools and Materials Needed
- Custom Ductwork: Flexible ducts, sheet metal, and duct fabrication tools.
- Transition Pieces: Custom-made transitions to fit between the furnace and the filter rack.
- Riser Boxes: Custom-built boxes to elevate the furnace and allow for bottom return air intake.
- Right-Angle Air Filters: Specialized filter configurations that fit into tight spaces.
Potential Costs and Time Estimates
- Custom Ductwork and Transitions: Costs can vary widely depending on materials and complexity, but expect to spend $100-$500 or more. Time estimates can range from a few hours to several days depending on the complexity of the job.
- Riser Boxes and Stacked Media Cabinets: These custom solutions can be more expensive, potentially costing $500-$2,000 or more. Time estimates can range from several hours to multiple days.
- Right-Angle Air Filters: These are generally less expensive, costing around $50-$200, and can be installed in a few hours.
