Replacing a dirty filter on time protects equipment performance. You can compare compatible 20x25x1 filters here to find the right match for your unit.
Parts with these numbers
20" x 25" x 1" MERV 8 Multi-Pleated Panel Filter (Hart & Cooley 102700009)
20" x 25" x 1" Fiberglass Throw Away Replacement Filter (Hart & Cooley 274200250)
- Length x width: match the size on the frame
- Depth: must match the slot: 1, 2, 4 or 5 in
- MERV: pick what your system can handle
Understanding 20x25x1 Filter Dimensions
The numbers 20x25x1 represent the nominal size of the filter. Nominal dimensions are rounded measurements printed on the frame for easy identification.
The first two numbers are length and width, measuring 20 inches by 25 inches. The last number is the thickness, which is 1 inch. The actual physical dimensions are slightly smaller than these labeled numbers so the frame slides easily into the filter track.
- Nominal length: 20 inches
- Nominal width: 25 inches
- Nominal depth: 1 inch
- Slot thickness: Must match your 1 inch cabinet opening
Reading the Label on Your Old Filter
Look at the outer cardboard edge of your current filter to confirm its size. Manufacturers print the nominal dimensions right along the frame.
You will also find an airflow arrow printed along the outer edge. This arrow shows which way air must pass through the media to keep the frame rigid. Some labels also list an efficiency rating, such as MERV.
Comparing 20x25x1 Filter Options
Two different styles share this nominal size. They use different materials and constructions depending on your equipment needs.
The Hart & Cooley 102700009 is a pleated panel filter made from synthetic material with a MERV 8 rating. The Hart & Cooley 274200250 is a fiberglass throw away replacement filter that replaces part number 20X25X1PSF. Check what your system can handle when choosing between synthetic pleated and fiberglass media.
- Hart & Cooley 102700009: Synthetic material, pleated design, MERV 8 rating
- Hart & Cooley 274200250: Fiberglass material, throw away design, replaces 20X25X1PSF
Signs Your Air Filter Needs Changing
Air filters collect dust as air circulates through your home. Over time, that buildup clogs the media and reduces air movement through your ductwork.
Inspect a 1 in filter every month. If the filter media looks gray, matted with dust, or bowed inward, it needs to be replaced. Most 1 in filters require a fresh replacement every 1 to 3 months.
How to confirm it fits
- Look at the cardboard frame on your old filter and confirm it reads 20" x 25" x 1".
- Measure your filter rack to verify it is built for a 1 inch deep filter, and never force a thicker filter into the slot.
- Check the airflow direction arrow on the old frame so you know which way your system pulls air.
- Check your equipment manual to verify that a MERV 8 rating works well with your system.
Questions
Which way should the airflow arrow point?
Point the airflow arrow toward the furnace or air handler, away from the return duct.
How often should I check or change a 1 inch filter?
Check a 1 in filter every month. Most need a change every 1 to 3 months.
What parts does the fiberglass filter replace?
The Hart & Cooley 274200250 fiberglass filter replaces part number 20X25X1PSF.
Can higher MERV ratings affect my system?
Many homes use MERV 8 to 11. Higher MERV catches more dust, but it can slow airflow on some systems.
Related guides
Brand names and part numbers are used only to show fit. HVAC Fitter is not affiliated with, authorized by, or endorsed by any equipment maker. If you are not sure a repair is safe for you, call a licensed HVAC technician.