What filter fits a Winix C545 Filter S air purifier?
The Winix C545 Filter S air purifier uses the AXPPF174 replacement filter.
Key takeaways
- Replacement filter part number: AXPPF174 (Winix).
- True HEPA with an activated carbon layer.
- Replace about every 12 months.
- A cheaper aftermarket filter can fit the same slot - check reviews for real-world fit before buying.
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Frequently asked
What filter fits a Winix C545 Filter S air purifier?
The Winix C545 Filter S uses the AXPPF174 (AIRx Replacement HEPA Filter Kit for Winix C545 Filter S).
Is the AXPPF174 True HEPA?
Yes - the AXPPF174 is a True HEPA filter, meaning it's rated to capture at least 99.97% of 0.3-micron particles.
How often should I replace the AXPPF174?
About every 12 months under typical use, or sooner if airflow drops or your purifier's filter indicator lights up.
Should I buy the OEM filter or an aftermarket one?
The genuine Winix AXPPF174 is the safe, exact-fit choice. A cheaper aftermarket filter can fit the same slot too - check reviews for real-world fit and filtration performance before buying, since air purifier filters generally aren't independently certified the way NSF-listed water filters are.