Goodman Furnace Filter Location and How to Access and Replace It

The location of a Goodman furnace filter varies by model and installation, but knowing where to find it and how to replace it quickly improves airflow, efficiency, and indoor air quality. This article explains common filter locations, step-by-step access and replacement, recommended filter types, troubleshooting tips, and maintenance intervals for Goodman furnaces.

Topic	Quick Answer
Typical Filter Locations	Return air duct, blower compartment, or furnace cabinet side/door
Filter Types	Disposable fiberglass, pleated MERV 8–13, washable (less common)
Replacement Frequency	Every 1–3 months for disposable filters; 6–12 months for higher-efficiency in low-dust homes
Common Sizes	16×20, 20×20, 16×25, 20×25 (confirm actual size on filter frame)

How Goodman Furnace Filter Location Varies By System

Goodman furnaces are installed in different configurations: upflow, downflow, or horizontal. Filter location depends on the configuration and whether the system uses a separate air handler or return-air grille. Typical placements are in the return duct near the air handler, inside the furnace cabinet next to the blower, or behind a return-air grille in the wall or ceiling.

Upflow Furnaces

In upflow models the blower sits above the heat exchanger and air moves upward. Filters are often located in the bottom return-air opening or in a removable slot on the furnace cabinet’s side or front. This placement allows air to be filtered before entering the blower.

Downflow Furnaces

Downflow furnaces draw air downward. The filter may be positioned at the top of the cabinet, inside an upper access panel, or in the return duct above the unit. In basements or attics with downflow units, the filter can be in a duct boot or ceiling return.

Horizontal Furnaces

Horizontal furnaces, usually in attics or crawlspaces, place the blower and heat exchanger on their side. Filters in these systems are commonly accessed from a side panel or located in the return duct immediately adjacent to the furnace.

Where To Look First: Quick Inspection Steps

To locate the filter on a Goodman furnace, start with these steps: turn off power, visually inspect the return-air grille, check the furnace front and side panels, and follow the return duct to the air handler. Always shut power off at the thermostat and switch or circuit breaker before opening panels.

1. Turn Off Power: Use furnace switch or breaker.
2. Inspect Return-Grille: Filters may be behind wall or ceiling grilles.
3. Open Furnace Panels: Remove front, side, or blower access panels.
4. Follow Ductwork: Trace return duct to a filter slot or door.

Detailed Steps To Access And Replace The Filter

This section provides a step-by-step guide to safely remove and replace the filter in most Goodman furnace models. Each step is concise to make the process straightforward.

Safety And Preparation

Before starting, turn off power to the furnace at the service switch and breaker. Wear gloves and eye protection when handling a dirty filter. Have the correct replacement filter size and type on hand.

Steps For Filters In Return-Air Grilles

1. Locate the Return Grille: Commonly on a wall or ceiling near the furnace.
2. Open the Grille or Unscrew Frame: Some grilles have clips; others require a screwdriver.
3. Slide Out the Filter: Note airflow arrow and orientation.
4. Insert New Filter In Same Direction: Ensure proper fit and arrow pointing toward the furnace.
5. Close Grille and Restore Power.

Steps For Filters Inside The Furnace Cabinet

1. Turn Off Power: Confirm power is off before touching panels.
2. Remove Front Or Side Panel: Unscrew or unclip the access panel.
3. Locate The Filter Slot: Typically adjacent to the blower housing.
4. Pull Out The Old Filter Carefully: Watch for dust and debris.
5. Install New Filter With Correct Orientation: Arrow toward blower/heat exchanger.
6. Reattach Panel And Restore Power.

Identifying The Correct Filter Size And Type

Filters are identified by dimensions printed on the frame. If the frame is unreadable, measure length, width, and depth in inches. Using the correct size prevents air bypass and maintains efficiency.

Common Filter Sizes For Goodman Furnaces

Common sizes include 16x20x1, 20x20x1, 16x25x1, and 20x25x1. Thicker filters (2–4 inches) are used in certain air handlers and yield better dust-holding capacity but require compatible filter racks.

Filter Types And MERV Ratings

Disposable fiberglass filters are low-cost with MERV 1–4. Pleated filters offer MERV 8–13 for better capture of dust, pollen, and pet dander. High-efficiency filters (MERV 13+) can improve indoor air quality but may restrict airflow if the furnace or blower is undersized. Consult manufacturer recommendations before choosing high-MERV filters.

Maintenance Frequency And Best Practices

Replacement intervals depend on filter type, occupancy, pets, and indoor air quality goals. Typical guidelines help maintain performance and prevent strain on the furnace.

• Standard Disposable Filters: Replace every 1–3 months.
• Pleated Filters (MERV 8–12): Replace every 3 months or according to dust load.
• High-Efficiency Filters (MERV 13+): Replace every 2–3 months; monitor by pressure drop if possible.
• Washable Filters: Clean monthly and inspect for damage.

Homes with pets, smokers, or high dust should check filters monthly. During heavy use seasons, check filters at the start of each month for better performance.

Troubleshooting Common Filter Location Issues

Several problems can make locating or replacing the filter difficult. This section addresses common issues and recommended actions.

Can’t Find A Filter Slot

If no obvious slot exists, the system may use a remote filter box in the return duct or a grille-mounted filter. Trace the return duct back to the furnace and inspect for an inline filter cabinet or door.

Filter Too Tight Or Too Loose

A filter that fits too tightly can be hard to remove; one that’s loose allows airflow bypass. Use the exact size and, if necessary, add a thin foam gasket to seal small gaps for proper airflow through the filter media.

High Pressure Drop After Installing Filter

A sudden reduction in airflow after replacing a filter can result from using too high a MERV rating or incorrect depth. Revert to a filter with lower MERV or consult an HVAC technician to verify blower capacity and static pressure.

When To Call A Professional

Some situations require an HVAC technician: if the filter slot is inaccessible, the furnace shows heat exchanger or airflow problems, or if a high-MERV filter causes system strain. A professional can install a compatible filter rack or retrofit a media filter cabinet.

Improving Filter Access And Convenience

For easier maintenance, homeowners can request a removable filter rack, install a pull-out filter drawer in the return duct, or use return grilles designed for quick filter changes. These modifications should be performed by qualified technicians to ensure HVAC performance and safety.

Energy And Air Quality Considerations

Using a clean, properly rated filter maintains airflow, improves efficiency, and reduces wear on the furnace. Higher-efficiency filters capture smaller particles and allergens but can raise static pressure. A balanced approach optimizes both energy use and indoor air quality.

Filter Impact On System Efficiency

A dirty or undersized filter reduces airflow, forcing the blower to run longer and increasing energy consumption. Regular filter replacement improves heat transfer efficiency and may lower utility costs.

Indoor Air Quality Trade-Offs

Choosing a higher MERV filter enhances particulate removal but may require blower upgrades. For homes needing improved air quality, combining a moderate MERV filter with supplemental air cleaning (UV lights or portable air purifiers) can be effective.

Frequently Asked Questions About Goodman Furnace Filter Location

How Often Should Goodman Furnace Filters Be Replaced?

Replace disposable filters every 1–3 months and pleated filters every 3 months, adjusting based on home conditions. Check monthly during heavy-use seasons or if occupants have allergies.

Can A Homeowner Use Any Filter MERV Rating?

While homeowners can buy filters with higher MERV ratings, they should confirm compatibility with the furnace blower and air handler. Overly restrictive filters can reduce airflow and damage the system.

What If The Filter Is Behind The Furnace Panel And Hard To Reach?

If access is difficult, a qualified HVAC technician can relocate the filter to an easier location or install an external filter rack. This improves safety and simplifies regular maintenance.

Does The Furnace Always Have A Filter?

Most Goodman furnaces require a filter, but some systems use whole-home media filters installed remotely. If unsure, inspect the return duct and consult the furnace manual or a service technician.

Resources And Where To Find Model-Specific Information

For model-specific filter location and replacement instructions, consult the Goodman furnace owner’s manual or the Goodman Manufacturing website. HVAC forums and professional technicians also provide practical, model-based guidance.

Goodman manuals include diagrams showing panel removal and filter slots. Serial and model numbers on the furnace nameplate help find the correct manual and recommended filter specifications.

For installation changes or concerns about filter airflow and system compatibility, consider scheduling a professional HVAC inspection or using authorized Goodman service providers.

Key Takeaway: Locating a Goodman furnace filter usually requires inspecting the return grille, furnace panels, or return duct. Proper size, orientation, and timely replacement maintain efficiency and indoor air quality while avoiding system strain.