Collection: Nordic Pure

Nordic Pure Furnace and AC Air Filters by Thickness, Size and MERV

This page collects Nordic Pure pleated air filters for furnaces and central air systems in 1, 2, 4 and 5-inch thicknesses, in MERV 7, 8, 10, 12, 13 and 14, including several Plus Carbon options. One listing from the AirPurete brand (a MERV 11, 20x25x5 2-pack) is also grouped here. Read the nominal size printed on the edge of your current filter, including the thickness, and match all three numbers.

Find Your Nordic Pure Filter

Each size links to a listing. The MERV ratings and pack sizes show what the Nordic Pure listings offer for that size. Open the link to see the exact options.

Nominal size (inches) Thickness MERV options Pack sizes
16x20x1 1 inch 7, 8 Plus Carbon, 12 6
16x25x1 1 inch 7, 8, 12 2, 6
20x20x1 1 inch 7, 8 Plus Carbon, 12 6
20x25x1 1 inch 7, 8, 12 2, 4, 6
16x25x2 2 inch 10, 12, 14 3
16x25x4 4 inch 8 Plus Carbon, 10, 12 2
20x25x4 4 inch 7, 10, 12 2
16x25x5 5 inch 10, 12, 13 1, 2
20x20x5 5 inch 10, 12, 13 Plus Carbon 2
20x25x5 5 inch 8 Plus Carbon, 12, 12 Plus Carbon (plus AirPurete MERV 11) 2

Match the Thickness, Not Just the Length and Width

A filter only fits the slot depth it was made for, so a 4-inch filter will not fit a 1-inch slot and the reverse. Several 5-inch listings, such as the 16x25x5, are described as replacements for Honeywell or Lennox media cabinets, so check the product page for the housing it names.

Choosing a MERV Rating

MERV is a scale of how well a filter captures particles, with higher numbers capturing smaller particles. Higher ratings also add airflow resistance, so check your furnace or air handler manual for the highest MERV it recommends. Plus Carbon listings add a carbon layer intended to help with odors. Check each product page for what it states.

How Often to Replace

Thicker 4 and 5-inch filters generally go longer between changes than 1-inch filters, but the right interval depends on your system, pets, dust and run time. Check the filter regularly and follow your equipment manufacturer's guidance.

Our Fit Guarantee and Shipping

US orders ship free. If a filter listed as compatible with your system does not fit, our Fit Guarantee covers it within 30 days of delivery. See our Aerostar air filters and the full air filter range for other options.

Nordic Pure Filter Questions

How do I find the size of my air filter?

Look at the printed size on the edge of your current filter, such as 20x25x4. The thickness is the third number, and it must match.

What does Plus Carbon mean?

Plus Carbon listings include a carbon layer in addition to the pleated media. See the product page for what the filter claims to reduce.

Do these fit my Honeywell or Lennox media cabinet?

Some 5-inch listings name Honeywell or Lennox replacements. Check the model named on the product page against your cabinet, or email us the model.