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- Product label: Special Order
Koch Multi-Pleat XL8 18 x 21 x 1 MERV 8 Pleated Air Filter - 12 Pack
Sale price
$273.36 USD
Regular price
Regular price
$273.36 USD
Unit price
$22.78
item
Koch Multi-Pleat XL8 18 x 21 x 1 MERV 8 Pleated Air Filter - 12 Pack
Sale price
$273.36 USD
Regular price
Regular price
$273.36 USD
Unit price
$22.78
item
Product Details
The Koch Multi-Pleat XL8 is a MERV 8 extended-surface pleated filter for gas and oil furnaces, heat pumps and AC air handlers. It fits any system that takes an 18 x 21 x 1 filter (18x21x1). This case contains 12 filters. At a quarterly change, that is three years of filters for one system, or one year for three systems.
Multi-Pleat XL8 uses 100% mechanical filter media, so its efficiency does not depend on an electrostatic charge that can fade over time. A galvanized expanded-metal support grid is laminated to the media to hold the pleats in shape, the pleats are bonded to the frame to prevent air bypass, and the double-wall, moisture-resistant beverage-board frame with reinforced corners stays rigid in humid conditions.
Is This the Right Size?
Air filters are sold by nominal size, the rounded size printed on the frame of your current filter. The filter itself is made slightly smaller so it slides into the filter slot — typically about 1/2" under nominal on length and width, and 3/4" deep for a 1" filter. Match the nominal size printed on your old filter, not a tape measurement of the slot.
Not sure? Send us a photo of the label on your current filter and we will confirm the match before you order.
Specifications
| Brand | Koch Filter |
| Series | Multi-Pleat XL8 |
| Koch Part Number | P8S1-180-210 |
| Nominal Size | 18 x 21 x 1 |
| MERV Rating | MERV 8 | MERV-A 8 (ASHRAE 52.2-2007) |
| Media | 100% mechanical synthetic media |
| Media Support | Galvanized expanded metal, laminated to media |
| Frame | Double-wall moisture-resistant beverage board, reinforced corners |
| Quantity | 12 filters |
What MERV 8 Captures
MERV 8 is the everyday standard for residential systems. Under ASHRAE 52.2 a MERV 8 filter captures at least 70% of particles in the 3–10 micron range (household dust, lint, pollen, dust mite debris and mold spores) while keeping airflow resistance low enough for virtually any furnace or air handler.
Replacement Schedule
Check the filter monthly and replace it at least every three months — sooner in homes with pets, during renovation work, or whenever it looks loaded with dust. Install it with the airflow arrow on the frame pointing toward the blower.
In commercial systems, change the filter when pressure drop across it reaches 1.0" w.g., Koch's recommended final resistance for this filter.
Shop all Koch Filter air filters.
Genuine Koch Filter Replacement Filters
Koch Multi-Pleat filters sold by the full case, with the Koch part number, actual dimensions and case quantity listed on every product.
- Koch part number on every listing
- Case pricing on every filter
- Common and hard-to-find sizes
Koch Filter FAQs
Returns & Exchanges
We want every order to go smoothly, and if something is not right we want to make it right. At the same time, for the health and safety of everyone — our team, other customers, and the facilities these products are used in — we cannot resell opened or used filtration and air quality products. Our policy below is built around that reality. If you have any questions about a product before ordering, please reach out — we would rather help you get the right thing the first time than deal with a return after the fact.
Eligibility
Opened or used items are not eligible for return or refund under any circumstances. Products designated as Special Order, Clearance, Discontinued, or Final Sale along with Equipment are not eligible for return or exchange. All other returns require items to be unused, in new condition, and in original packaging with all accessories and documentation included.
30-Day Return Policy
Unopened, unused items may be returned within 30 days of delivery, subject to a restocking fee of at least 25% of the purchase price. Original shipping costs are not refunded. Return shipping is the buyer's responsibility. A Return Material Authorization (RMA) number is required before shipping any return — contact us first at Help@HEPAFilterSales.com to receive return instructions. Returns sent without an RMA may be refused.
Refunds are processed within 10 business days of receiving and inspecting the returned item. You will be notified by email when your refund has been issued.
Exchanges — Standard Restocking Charge Waived
Exchanges for unopened, unused items are not subject to a restocking fee. Contact us at Help@HEPAFilterSales.com before returning any item to arrange an exchange and receive expert advice on the correct solution.
Order Cancellations
Contact us immediately if you need to cancel an order. Not all orders can be cancelled once placed — freight and special-order items in particular may ship before a cancellation can be processed.
Damaged or Incorrect Items
If your order arrives damaged, note the damage with the delivery carrier at time of delivery, photograph the damage, and email us within 48 hours of delivery at Help@HEPAFilterSales.com. We will arrange return shipping and send a replacement at no additional cost to you.
If you receive an incorrect item (compared to what was ordered), email us your order number and a description of the issue. We will arrange return shipping and send the correct item at no cost to you.
Defective Items
Suspected product defects and performance issues are warranty matters handled directly by the manufacturer — they are not eligible for return or return shipping reimbursement from HEPA Filter Sales, LLC. Contact us and we will provide manufacturer contact information to assist with a warranty claim.
For More Information, please take a moment to review our governing policies:
Returns & Refunds Policy
Shipping Policy
Purchase Options & Subscription Policy