What filter/pad fits a Aprilaire 445 humidifier?
The Aprilaire 445 humidifier uses the 12 replacement furnace/whole-house water panel.
Key takeaways
- Replacement part number: 12 (Aprilaire).
- This is a furnace/whole-house water panel, not a portable-unit wick.
- Replace once per humidifying season, or sooner if it's visibly scaled or discolored.
- A cheaper aftermarket filter can fit the same slot - check reviews for real-world fit before buying.
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Also known as
The 12 replaces (and is cross-referenced under) these part numbers: A12PR, A12W-PDQ-6, A12-PR, HC18P1009.
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Frequently asked
What filter/pad fits a Aprilaire 445 humidifier?
The Aprilaire 445 uses the 12 (Replacement Elite Water Panel for Whole House Humidifiers (#12) -), a furnace/whole-house water panel.
Is the 12 a wick or a furnace pad?
The 12 is a furnace/whole-house humidifier water panel, not a portable-unit wick.
How often should I replace the 12?
We don't have a manufacturer-listed replacement interval for the 12 - a common default is once per humidifying season, or sooner if it's visibly scaled or discolored.
Should I buy the OEM filter or an aftermarket one?
The genuine Aprilaire 12 is the safe, exact-fit choice. A cheaper aftermarket wick or pad can fit the same slot too - check reviews for real-world fit and how well it wicks water before buying, since humidifier filters aren't independently certified the way NSF-listed water filters are.