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Replacement filter set

GermGuardian Filter K – FLT9400 replacement filter

Filter K (FLT9400) fits GermGuardian AC9400W according to the cited GermGuardian source.

Official manufacturer Filter K FLT9400 Check official GermGuardian availability Non-affiliate link to the cited official product page.
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Quick fit check

Filter K fit and replacement facts

Part numberFLT9400
Compatible models1
Filter roleReplacement filter set

The cited page describes FLT9400 as a True HEPA and treated-carbon replacement filter but does not state a replacement interval.

Compatible GermGuardian models

Follow a model link for its complete primary, optional, specialty, and alternative filter list.

Model Filter Part number Role Source Marketplace
GermGuardian AC9400W Filter K FLT9400 Replacement filter set Guardian Technologies GermGuardian FLT9400 - Filter K Check prices

Buying checklist

What to check in a filter listing

Confirm that the listing names part FLT9400 and one of the compatible models: GermGuardian AC9400W. Similar-looking filters are not proof of fit.

Decide whether you want an OEM or aftermarket filter, then compare the included pieces, product photos, seller details, delivery estimate, and total price.

Care guidance

Replacement schedule

The cited page describes FLT9400 as a True HEPA and treated-carbon replacement filter but does not state a replacement interval.

Usage conditions can affect service life. Follow the cited manufacturer guidance for this part.

Frequently asked questions

How often should I replace the GermGuardian Filter K (FLT9400)?

The cited page describes FLT9400 as a True HEPA and treated-carbon replacement filter but does not state a replacement interval.

Which GermGuardian models use the Filter K FLT9400?

According to the official GermGuardian product page, Filter K (FLT9400) fits GermGuardian AC9400W. Verify the model label on your unit before ordering.

Do aftermarket FLT9400 filters work?

Marketplace listings may be from the manufacturer or a third party. Match the exact part number FLT9400, review the listing details, and verify the model label on your unit before buying.

Manufacturer source

Official Guardian Technologies product page identifies Filter K, SKU FLT9400, as compatible with model AC9400W.

Guardian Technologies GermGuardian FLT9400 - Filter K

Source compatibility checked 2026-07-22. Recheck the listing and your purifier label before ordering.