Searching for a Frigidaire water filter replacement and landing on multiple results with slightly different names and part numbers is more common than it should be. The ULTRAWF, WF3CB, and EPTWFU01 all appear in Frigidaire refrigerator filter searches, and they are not interchangeable. Ordering the wrong one means the filter either does not fit the housing, does not seat correctly, or reduces water flow to a trickle. This post covers what the ULTRAWF is, which Frigidaire refrigerators use it, how to confirm the filter code before ordering, and the most common mistakes buyers make when replacing it.
Why Frigidaire Filter Numbers Cause So Much Confusion
Frigidaire has used several different filtration systems across its refrigerator lineup over the years. The PureSource 2 system uses the WF2CB. The PureSource 3 system uses the WF3CB. The PureSource Ultra system uses the ULTRAWF. The PureSource Ultra II system uses the EPTWFU01. Each system uses a different housing design, and the filters are not interchangeable in most cases, with one exception that catches buyers off guard regularly, which is covered below.
The names look similar enough that many buyers assume any Frigidaire filter fits any Frigidaire refrigerator. That assumption leads to a lot of returns.
Where to Find Your Filter Part Number Before Ordering
The fastest way to avoid ordering the wrong filter is to check the part number before searching. Here is where to look:
Step 1. Open the refrigerator door and locate the filter housing. On most Frigidaire PureSource Ultra models, the filter housing is mounted on the ceiling of the fresh food compartment.
Step 2. Check the label on the current filter. The part number -- ULTRAWF, WF3CB, EPTWFU01, or another code -- is printed directly on the filter body.
Step 3. If the current filter label has worn off, check the refrigerator model number on the sticker inside the door frame. That model number can be used to cross-reference the correct filter code before ordering.
Step 4. If neither is visible, check the refrigerator use and care manual. The filter part number is listed in the maintenance or filter replacement section.
What Is the Frigidaire ULTRAWF Filter
The Frigidaire ULTRAWF uses a premium activated carbon block with a 0.5 micron rating, reducing chlorine taste and odor, Class I particulates, lead, mercury, cysts including Cryptosporidium and Giardia, select VOCs, and trace contaminants. It is rated for 200 gallons or six months, whichever comes first. It fits Frigidaire, Frigidaire Gallery, and Frigidaire Professional side-by-side and French door refrigerators with PureSource Ultra ice and water filtration.
The ULTRAWF uses a push-to-release, push-to-lock installation design. The filter housing sits on the ceiling of the fresh food compartment rather than in the upper right corner like some other Frigidaire filter systems. This ceiling-mount position is a quick visual confirmation that the refrigerator uses the ULTRAWF rather than the EPTWFU01 or WF3CB.
What Is the Frigidaire EPTWFU01 Filter
The EPTWFU01 is the PureSource Ultra II filter, an updated filtration system introduced on Frigidaire French door and side-by-side models produced after 2015. It uses a push-and-twist installation in the upper right corner inside the refrigerator compartment rather than a ceiling-mount housing. The EPTWFU01 carries NSF 42, 53, and 401 certifications, covering a broader contaminant list than the ULTRAWF. It is rated for 200 gallons or six months.
The EPTWFU01 and ULTRAWF are not interchangeable. They use different housing designs and different installation methods. The most reliable way to confirm which one the refrigerator uses is to check the label on the current filter before ordering.
What Is the Frigidaire WF3CB Filter
The WF3CB is the PureSource 3 filter used in an earlier generation of Frigidaire side-by-side refrigerators. The ULTRAWF can be used as an upgraded filter option in refrigerators that previously required the WF3CB. This cross-compatibility is the one exception that causes confusion. Some buyers with older Frigidaire refrigerators originally using the WF3CB can upgrade to the ULTRAWF if the housing accepts it. Confirming this upgrade compatibility with the specific refrigerator model number before ordering is the safer approach.
Is the ULTRAWF the Same as the EPTWFU01
No. The ULTRAWF and EPTWFU01 are separate filters designed for different Frigidaire filtration systems. The ULTRAWF fits the PureSource Ultra system with a ceiling-mount housing. The EPTWFU01 fits the PureSource Ultra II system with an upper right corner push-and-twist housing. They use different installation designs, different housings, and different part number codes.
The naming similarity between PureSource Ultra and PureSource Ultra II creates most of the confusion. Both systems are Frigidaire and both use activated carbon block filtration, but the physical filter cartridges are not the same and will not seat correctly in each other's housing.
Compatibility Checklist Before Ordering the ULTRAWF
Before placing an order, run through this checklist:
- Confirm the current filter label shows ULTRAWF, 242017800, 242017801, or A0094E28261
- Confirm the filter housing is located on the ceiling of the fresh food compartment
- Confirm the refrigerator uses the PureSource Ultra filtration system, not PureSource Ultra II
- Confirm the refrigerator model is a Frigidaire, Frigidaire Gallery, or Frigidaire Professional side-by-side or French door model
- If upgrading from WF3CB, confirm the refrigerator housing accepts the ULTRAWF before ordering
If all five points check out, the ULTRAWF is the correct replacement. If the current filter label shows EPTWFU01, the EPTWFU01 product page covers the correct replacement for that system.
Common Mistakes When Buying a Frigidaire ULTRAWF Replacement
- Ordering by appearance rather than part number. The ULTRAWF and EPTWFU01 look similar but fit different housings. Always check the part number on the current filter before ordering.
- Assuming any Frigidaire filter fits any Frigidaire refrigerator. Frigidaire uses at least four different filter systems, each with a different code and housing design. The brand name alone does not confirm compatibility.
- Skipping the flush after installation. Run water through the new filter for 3 minutes and discard before drinking. Cloudy water or an off taste after installation is usually just air and carbon particles, not a defective filter.
- Not resetting the filter indicator light. The indicator does not reset automatically. Check the use and care manual for the reset process or the light stays on after a successful swap.
- Waiting too long past six months. A saturated filter may start releasing previously trapped contaminants. Replacing on schedule is more reliable than waiting for visible signs.
When to Replace or Order a New ULTRAWF Filter
Replace the ULTRAWF when any of the following apply:
- Six months have passed since the last replacement
- The filter indicator light on the refrigerator panel has activated
- Water picks up a faint chlorine taste or flat odor
- Dispenser flow has slowed noticeably
- Ice is coming out cloudy or with an off smell
- The refrigerator is used by three or more people daily and the last replacement was four to five months ago
Recommended Replacement
The Frigidaire ULTRAWF PureSource Ultra refrigerator water filter is available on the product page at purefridgewater.com. Confirm the current filter label shows ULTRAWF or one of the compatible part numbers listed above before ordering. If the current filter label shows EPTWFU01, the EPTWFU01 product page covers that replacement.
Shop Frigidaire ULTRAWF Filter from purefridgewater.
FAQs
Is the ULTRAWF filter the same as the WF3CB?
No. The WF3CB is the PureSource 3 filter for an earlier Frigidaire side-by-side generation. The ULTRAWF is the PureSource Ultra filter for a newer generation. In some cases the ULTRAWF can be used as an upgrade in refrigerators previously requiring the WF3CB, but this depends on the specific refrigerator model and housing. Always confirm compatibility before ordering an upgrade.
Does the ULTRAWF reduce lead and mercury?
Yes. The ULTRAWF uses a premium activated carbon block with a 0.5 micron rating that reduces lead, mercury, chlorine taste and odor, cysts, and select VOCs. Results may vary depending on local water supply conditions.
How do I know if my Frigidaire refrigerator uses the ULTRAWF or the EPTWFU01?
Check the label on the current filter. The ULTRAWF housing is mounted on the ceiling of the fresh food compartment. The EPTWFU01 installs in the upper right corner using a push-and-twist design. These two installation positions are the quickest visual way to confirm which system the refrigerator uses.
Can aftermarket ULTRAWF replacements be used safely?
Aftermarket replacements are available for the ULTRAWF at lower price points. Performance varies between manufacturers. The key specification to verify is NSF 42 and NSF 53 certification. Aftermarket filters without independent certification may claim similar performance but carry no third-party verification.
What happens if the ULTRAWF is not replaced on time?
Using an expired ULTRAWF filter can reduce filtration effectiveness and may slow water flow. A saturated carbon block may also release previously trapped contaminants back into the water. Replacing on the six month or 200 gallon schedule maintains consistent performance through the full service life.