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Filters Fast - Filter. Purify. Protect.

Filters Fast® Replacement for Lennox 91X23 MERV 8 Furnace & AC Air Filter - 6-Pack

91X23 FF

 4.85 (380) Read The Reviews!
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$62.95
Only $10.49 per Filter
Retail: $81.99 /ea
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Retail: $81.99
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M8 6pk Sizes - Some Sizes Have Additional Costs :
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Frequently Bought With This Item

The Filters Fast® Replacement for Lennox 91X23 MERV 8 Furnace & AC Air Filter - 6-Pack effectively reduces pollen, dust, pet dander and other allergens from indoor air. Removing these airborne particles alleviates allergies and sinus irritation that can cause watery eyes, itchy throat, coughing, and sneezing. Aside from the health benefits, this HVAC air filter in your home will also extend the life of your heating and cooling system by making it work more efficiently.

Note: Our MERV 8 filters do not come individually wrapped. These filters do not contain fiberglass.

Specifications:

  • Brand: Filters Fast®
  • Part Number: 91X23 FF
  • Replaces Part Number: 91X23
  • Pack Size: 6
  • Filter Life: 1 - 3 months
  • MERV Rating: 8
  • Filter Type: Pleated
  • Material: Synthetic
  • Tolerance: (+/- ) 1/8" tolerance
  • For residential use only

How do you install the Filters Fast® Replacement for Lennox 91X23?

  1. Once your air filters arrive, gather your supplies including a ladder (if needed,) safety goggles, gloves, a mask, and a disposable bag.
  2. Remove the metal grate from your air return.
  3. Carefully remove the used air filter and place it immediately and gently into the disposable bag. Then tie the bag sealed.
  4. Place the new air filter in place of the filter you just removed and replace the metal grille.

How often should you replace the Filters Fast® Replacement for Lennox 91X23?

  • Changing your Filters Fast® Replacement for Lennox 91X23 is a very quick and easy process that should be done once every one to three months.

What contaminants does the Filters Fast® Replacement for Lennox 91X23 reduce?

  • The Filters Fast® Replacement for Lennox 91X23 is a MERV 8 air filter, which means that it reduces the following contaminants:

    • Dust
    • Pollen
    • Mold Spores
    • Other Common Airborne Allergens

Resources:

Compatible Parts:

The Filters Fast® Replacement for Lennox 91X23 MERV 8 Furnace & AC Air Filter - 6-Pack is the correct replacement for the following part numbers:

Part Number
  • 7100182284
  • 7100183959
  • 7100186818
  • 7100187098
  • 7100189227
  • 7100192557XXX
  • 7100268565
  • 7100288704
  • 7100288715
  • 7100288843
  • 9837DC-6
  • CP8.0119.7X35.76PK
  • CPR8.0116.5X21.6PFF
  • DLX91X24
  • DLX98N43
  • FFM8 6PK-0750751
  • FFM8 6PK-08081
  • FFM8 6PK-09111
  • FFM8 6PK-10101
  • FFM8 6PK-10161
  • FFM8 6PK-10201
  • FFM8 6PK-10241
  • FFM8 6PK-10251
  • FFM8 6PK-10301
  • FFM8 6PK-1151151
  • FFM8 6PK-12121
  • FFM8 6PK-12151
  • FFM8 6PK-12161
  • FFM8 6PK-12181
  • FFM8 6PK-12201
  • FFM8 6PK-12221
  • FFM8 6PK-12241
  • FFM8 6PK-12251
  • FFM8 6PK-12301
  • FFM8 6PK-12361
  • FFM8 6PK-132151
  • FFM8 6PK-13221
  • FFM8 6PK-14141
  • FFM8 6PK-141551
  • FFM8 6PK-14161
  • FFM8 6PK-14181
  • FFM8 6PK-14201
  • FFM8 6PK-14221
  • FFM8 6PK-14241
  • FFM8 6PK-14251
  • FFM8 6PK-14301
  • FFM8 6PK-14361
  • FFM8 6PK-15201
  • FFM8 6PK-15251
  • FFM8 6PK-15301
  • FFM8 6PK-16161
  • FFM8 6PK-16181
  • FFM8 6PK-16201
  • FFM8 6PK-16241
  • FFM8 6PK-16251
  • FFM8 6PK-16301
  • FFM8 6PK-16321
  • FFM8 6PK-17221
  • FFM8 6PK-1751751
  • FFM8 6PK-175211
  • FFM8 6PK-18181
  • FFM8 6PK-18201
  • FFM8 6PK-18221
  • FFM8 6PK-18241
  • FFM8 6PK-18251
  • FFM8 6PK-18301
  • FFM8 6PK-19241
  • FFM8 6PK-20201
  • FFM8 6PK-20211
  • FFM8 6PK-202151
  • FFM8 6PK-20221
  • FFM8 6PK-20241
  • FFM8 6PK-20251
  • FFM8 6PK-20261
  • FFM8 6PK-20301
  • FFM8 6PK-20361
  • FFM8 6PK-212451
  • FFM8 6PK-21523251
  • FFM8 6PK-22221
  • FFM8 6PK-22241
  • FFM8 6PK-24241
  • FFM8 6PK-24301
  • FFM8 6PK-25251
  • FFM8 6PK-28301
  • FFM8 6PK-30301
  • FFM8 6PK-30361
  • FFM8PLEAT1-12241
  • FFM8PLEAT1-16201
  • FFM8PLEAT1-16241
  • FFM8PLEAT1-16251
  • FFM8PLEAT1-18241
  • FFM8PLEAT1-20201
  • FFM8PLEAT1-20241
  • FFM8PLEAT1-20251
  • FFM8PLEAT1-20301
  • FFM8PLEAT1-24241
  • FFM8PLEAT612241
  • FFM8PLEAT616201
  • FFM8PLEAT616241
  • FFM8PLEAT616251
  • FFM8PLEAT618241
  • FFM8PLEAT620201
  • FFM8PLEAT620241
  • FFM8PLEAT620251
  • FFM8PLEAT620301
  • FFM8PLEAT624241
  • FLRSF1185 R
  • KFAFK0212MED R
  • LIGHTBLU-10201
  • LIGHTBLU-12121
  • LIGHTBLU-14141
  • LIGHTBLU-14201
  • LIGHTBLU-14251
  • LIGHTBLU-16201
  • LIGHTBLU-16251
  • LIGHTBLU-18181
  • LIGHTBLU-20201
  • LIGHTBLU-20251
  • LIGHTBLU-20301
  • LIGHTBLU-25251
  • PF8.0107.507.5A6PFF
  • PF8.010808A6PFF
  • PF8.010911A6PFF
  • PF8.0110106P
  • PF8.0110106PFF
  • PF8.0110166PFF
  • PF8.0110256PFF
  • PF8.0110306PFF
  • PF8.0111.511.5A6PFF
  • PF8.0112156PFF
  • PF8.0112166PFF
  • PF8.0112226PFF
  • PF8.011322A6PFF
  • PF8.011416A6P
  • PF8.011422A6PFF
  • PF8.0114366PFF
  • PF8.0115256PFF
  • PF8.0115306PFF
  • PF8.0116186PFF
  • PF8.0117.517.5A6PFF
  • PF8.0117.521A6PFF
  • PF8.0117226PFF
  • PF8.011924A6PFF
  • PF8.012026A6PFF
  • PF8.012124.5A6P
  • PF8.012224A6PFF
  • PF8.0128306PFF
  • PR08.011010PFF
  • PR08.011020PFF
  • PR08.011024PFF
  • PR08.011212PFF
  • PR08.011218PFF
  • PR08.011220PFF
  • PR08.011224PFF
  • PR08.011225PFF
  • PR08.011230PFF
  • PR08.011236PFF
  • PR08.011321.5APFF
  • PR08.011414PFF
  • PR08.011415.5APFF
  • PR08.011418PFF
  • PR08.011420PFF
  • PR08.011424PFF
  • PR08.011425PFF
  • PR08.011430PFF
  • PR08.011520PFF
  • PR08.011616PFF
  • PR08.011620PFF
  • PR08.011624PFF
  • PR08.011625PFF
  • PR08.011630PFF
  • PR08.011632PFF
  • PR08.011818PFF
  • PR08.011820PFF
  • PR08.011822PFF
  • PR08.011824PFF
  • PR08.011825PFF
  • PR08.011830PFF
  • PR08.012020PFF
  • PR08.012021.5APFF
  • PR08.012021PFF
  • PR08.012022PFF
  • PR08.012024PFF
  • PR08.012025PFF
  • PR08.012030PFF
  • PR08.0121.523.2APFF
  • PR08.012222PFF
  • PR08.012424PFF
  • PR08.012430PFF
  • PR08.012525PFF
  • PR08.013030PFF
  • PR08.013036PFF
  • American Standard FLRSF1185
  • Carrier KFAFK0212MED
  • DUPONT ALLERGEN AIR FILTERS
  • DUPONT BRONZE
  • DUPONT CONTRACTOR
  • DUPONT SILVER
  • DUPONT SILVER EXTRA
  • FILTRETE MICRO ALLERGEN FILTERS
  • Lennox 91X23
  • Trane FLRSF1185
  • No results for {X}

Compatible Models:

The Filters Fast® Replacement for Lennox 91X23 MERV 8 Furnace & AC Air Filter - 6-Pack is correct replacement for the following model numbers:

BrandModel NumberDescription
  • ALL FURNACES THAT REQUIRE A 15 X 20 X 1 AIR FILTER Air Filters Furnace Filters
  • ALL FURNACES THAT REQUIRE A 20 X 20 X 1 AIR FILTER Air Filters Furnace Filters
  • Carrier FA4ANC036 Air Filters Furnace Filters
  • Carrier FA4ANF030 Air Filters Furnace Filters
  • Carrier FA4ANF036 Air Filters Furnace Filters
  • Carrier FA4BNF036 Air Filters Furnace Filters
  • Carrier FA4CNC024 Air Filters Furnace Filters
  • Carrier FA4CNC030 Air Filters Furnace Filters
  • Carrier FA4CNF024000AAAA Air Filter
  • Carrier FA4CNF030 Air Filters Furnace Filters
  • Carrier FB4ANA036 Air Filters Furnace Filters
  • Carrier FB4ANF030 Air Filters Furnace Filters
  • Carrier FB4ANF036 Air Filters Furnace Filters
  • Carrier FB4BNF030 Air Filters Furnace Filters
  • Carrier FE4ANF002 Air Filters Furnace Filters
  • Carrier FX4ANF030 Air Filters Furnace Filters
  • Carrier FX4BNF030 Air Filters Furnace Filters
  • Carrier FX4CNF024 Air Filters Furnace Filters
  • Carrier PF1MNA036 Air Filters Furnace Filters
  • Filters Fast COMMERCIAL HVAC SYSTEMS Industrial Air
  • Filters Fast INDUSTRIAL AIR CLEANERS Industrial Air
  • No results for {X}

Customer Reviews:

Total Reviews: 380 Average Rating: 4.85 / 5.0

Filtersfast Reviews on Trust Pilot external site
Rick Freshman2026-09-13

I change at 60 days. Works good foe me.

Collected by Trustpilot.com
Gary2026-09-06

The filters were working fine on the last order& I would expect that quality will continue to.

Collected by Trustpilot.com
GARY BENNETT2026-08-28

works well.

Collected by Trustpilot.com
Brent2026-08-24

Great value for cost

Collected by Trustpilot.com
John F.2026-08-23

Well made.

Collected by Trustpilot.com
Debra Tremain2026-08-22

Good quality all the way around. I just don't give a5 star because there is room for improvement.\uD83D\uDC4D\uD83D\uDE0A

Collected by Trustpilot.com
Mahala2026-08-16

Great bargain.

Collected by Trustpilot.com
Bob and Liz Deleuil2026-08-11

product works to design and intent

Collected by Trustpilot.com
Patti Bauman2026-07-30

Hard to find in this size but glad your company has them and you can sign up for automatic reorders. It’s great to not have to think about reorders. They just come every 6 months.

Collected by Trustpilot.com
John Shackleford2026-07-24

My "highly favorable" Filters Fast recommendations should be good enough for any customer.

Collected by Trustpilot.com
Donald Gurzell2026-07-22

Well, the discount did not work but the price was not bad anyway. Shipment arrived undamaged and on time.

Collected by Trustpilot.com
customer2026-06-30

Great price and awesome product

Collected by Trustpilot.com
old camper2026-06-28

great product

Collected by Trustpilot.com
Harold Heath2026-06-27

Very good!

Collected by Trustpilot.com
Karen Jones2026-06-27

We are unable to find an odd size locally, so Filters Fastr is our go-to solution!

Collected by Trustpilot.com
Marlis Kuykendall2026-06-04

All good. Thank you.

Collected by Trustpilot.com
Paula Stork2026-05-29

Lesser quality than I was expecting. Will upgrade next time!

Collected by Trustpilot.com
Linda Harvell2026-05-26

Good filters for fair price

Collected by Trustpilot.com
georgette sterbenz2026-05-25

Fits my a/c perfectly. Love the ease of use . Great price and fast shipping.

Collected by Trustpilot.com
customer2026-05-25

Easy ordering & prompt shipping

Collected by Trustpilot.com

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FILTERS FAST SHIPPING POLICY

Filters Fast offers economy free shipping every day on U.S. orders over $99 when shipping to the lower 48 states. This free shipping offer excludes Alaska and Hawaii, P.O. Box or APO/FPO/DPO and international orders. Orders under $99 ship for a fee to most destinations within the contiguous United States (excluding Hawaii and Alaska).

Filters Fast offers expedited shipping. When selecting any expedited shipping method, such as FedEx 2nd day or Overnight, your Transaction will be processed and Products shipped out the next business day. Business days are Monday through Friday. Any expedited delivery requests that are placed Friday through Sunday will not result in Products shipped until Monday. If the following Monday falls on a FedEx recognized holiday, your Products will be shipped on Tuesday.

Most Products ship within 1-2 business days after Transaction finalization, unless otherwise stated on the Product page on the Services. Your final shipping cost and estimated delivery time frame will be available to you during checkout.

We offer guaranteed same-day shipping on select Products with your preferred delivery method every Tuesday, Wednesday, and Thursday. When guaranteed same-day shipping is available on a Product, we will state this on the Product page, with the label "Ready to Ship". The "order within" countdown timer provides the window of time in which you must checkout to have your Products ship out the same day the Transaction is finalized. If a Transaction is finalized right at or after 2:00 PM EST, the applicable Products will ship the next business day. Our business days are Monday through Friday. Filters Fast also reserves the right, without cause, to make changes to any same-day shipping timeframe as same-day shipping may become unavailable within the allotted timeframe due to changes in inventory or high-volume capacity when you finalized your Transaction.

Once the shipping label is created, you will receive an email confirmation with the tracking information for your package. A Product with the "Ready to Ship" label does not apply to the delivery speed.

For expedited shipping, you will still need to select your preferred shipping method at checkout. Filters Fast is not responsible or liable for any shipping delays of any kind, including carrier delays, inclement weather, government restrictions, labor shortages, gas or utilities shortages, acts of God, etc.

Please note, some Products are special order and may require a longer ship-out and/or delivery time frame. These Product have a shipping timeframe stated on the Product page on the Services.

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RETURNS AND REFUNDS POLICY

365-Day Satisfaction Guarantee

What You Need to Know:

Filters Fast is happy to accept returns on eligible items within 365 days of the original ship date. All returned Products are inspected and must be in a new, unused condition and contain all original parts, shrink wrap, protective seals, and components. Products with the "Satisfaction Guarantee Badge" are eligible for return in used condition. We will not accept the return of any other Products, including those that have been damaged other than by the applicable carrier, used, or do not contain all original parts, shrink wrap, protective seals, and components.

What Can Be Returned

Products are eligible for return if they:

Items That Cannot be Returned

We will not accept the return of any other Products, including those that have been damaged other than by the carrier, used, or do not contain all original parts, shrink wrap, protective seals, and components.

Items that cannot be returned:

Damaged or Defective Products

Water Quality Damages

Products damaged by water quality are not eligible for returns or refunds.

Installation Damage

Products damaged due to incorrect installation are not eligible for returns or refunds.

Product Misuse

Products that have been misused are not eligible for returns or refunds.

Shipping Damage

Filters Fast is not liable for damages to your Product(s) caused by the carrier. If your order arrives damaged, please report it as soon as possible through Your Account. Claims submitted within 365 days of the original ship date may be eligible for replacement or refund.

If you receive Products damaged by the carrier, we will work to resolve the issue, which may include you returning the Products to us. Please follow these steps to submit a claim for Products that the carrier damaged:

Return Restrictions

We encourage our customers to package their return carefully to avoid any damages in transit back to us.

Shipping & Return Labels

We gladly offer our customers free return shipping for eligible returns within the contiguous United States.

Customers in Alaska, Hawaii, Puerto Rico, and outside of the United States should contact our Customer Care Team for assistance.

Refund Information

We inspect all returned items when they arrive at our distribution facility. If you comply with the Returns Policy and your return is a result of a Filters Fast error in processing your Transaction or a defective Product that is protected by the Satisfaction Guarantee, we will refund the full cost of the Product. Additionally, if you comply with the Returns Policy and depending on the circumstances, we may refund the full cost of Products that are damaged due to the mishandling of the carrier.

Original outbound shipping charges are not refunded unless the return is a result of a Filters Fast error.

Refund Restrictions

After your return is received and inspected, refunds are typically processed within 1-2 business days. Depending on return shipping and your financial institution, the full refund may appear within 2-3 weeks. All refunds are issued to the original payment method.

Address Validation

Please double-check your shipping address before placing your order. Orders shipped to an incorrect address provided during checkout cannot be refunded or replaced until the original shipment is recovered.

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