Our catalog lists the Honeywell Home FC100A1029, a 16 x 25 x 4 media air filter rated MERV 11, as the replacement for CF100A1009.
The part that replaces it
16" X 25" Media Air Filter (Honeywell Home FC100A1029)
- CF100A1009
- Frame reads 16" x 25" x 4". Match the length, width and depth printed on your old filter.
- Depth fits the slot. A 1 in slot needs a 1 in filter. Never force a thicker one.
- MERV 11 works for your system. Higher MERV catches more dust but can slow airflow on some systems. Check your manual if unsure.
Why the size and depth come first
A filter has to match three numbers: length, width and depth. The FC100A1029 is listed as 16 x 25 x 4, so it is a 4 in deep filter.
Depth must match the slot, which is 1, 2, 4 or 5 in on different systems. Never force a thicker filter into a slot. The size printed on a filter is rounded, so a real filter measures a little under its label.
What MERV 11 means for your system
MERV is the rating for how much a filter catches. Many homes use MERV 8 to 11. A higher MERV catches more dust but can slow airflow on some systems.
Compare the MERV on your old filter with the MERV 11 listed here, and check your manual if you are not sure your system can handle it.
Putting the new filter in
Look for the airflow arrow on the frame. It points toward the furnace or air handler, away from the return duct. Slide the filter in with the arrow that way, and close the slot.
How to confirm it fits
- Look at the frame of your old filter for CF100A1009.
- Read the size on the frame. It should read 16 x 25 x 4 and must match the length, width and depth.
- Check that your filter slot is 4 in deep. Never force a thicker filter.
- Compare the MERV on the old filter with the MERV 11 on this one.
- Find the airflow arrow and plan to point it toward the furnace or air handler.
Questions
What is the replacement for CF100A1009?
Our catalog lists the Honeywell Home FC100A1029, a 16 x 25 x 4 media air filter rated MERV 11, as the replacement for CF100A1009.
Does the depth of the filter matter?
Yes. The depth must match the slot, which can be 1, 2, 4 or 5 in. This filter is 4 in deep, so it only suits a 4 in slot.
Which way does the airflow arrow point?
It points toward the furnace or air handler, away from the return duct.
Is MERV 11 right for my system?
Many homes use MERV 8 to 11. A higher MERV can slow airflow on some systems, so check your manual if you are not sure.
Related guides
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