Your Sub-Zero refrigerator depends on both a water filter and an air purification cartridge working together to deliver clean water and a consistently fresh interior environment. If you are looking at the 4204490 and 7042798 combo pack and are not completely sure it is the right replacement for your unit, this guide will walk you through exactly how to confirm compatibility before buying so you can order with confidence and avoid a costly mismatch.
Why Sub-Zero Combo Pack Numbers Can Be Confusing
Sub-Zero refrigerators use both a water filter and an air purification cartridge, and different model generations use different cartridge combinations. Here is why buyers frequently run into confusion when searching for the right combo pack to order:
- Both Sub-Zero combo packs share the same 4204490 water filter but pair it with different air cartridges, making it easy to order the wrong combo if you only check the water filter part number and not the air cartridge
- The 7042798 and 7007067 air cartridges look physically similar but are designed for different Sub-Zero model generations and are not interchangeable, so ordering by appearance rather than part number leads to a mismatch
- Searching broadly for a Sub-Zero combo pack to buy without specifying both part numbers often returns results for both combo variations, leaving buyers unsure which one applies to their specific refrigerator
- Older Sub-Zero models may show worn or faded cartridge labels making it difficult to read the correct part number without removing the existing cartridge entirely
- Some product listings group multiple compatible codes together which can make it unclear whether the 7042798 or the 7007067 is the correct air cartridge for a specific refrigerator model
Confirming both part numbers before placing your order is the single most important step in avoiding a compatibility issue with a Sub-Zero combo pack purchase.
Where to Find Your Sub-Zero Filter and Cartridge Part Numbers Before Buying
Follow these steps to locate the correct part numbers for both the water filter and air cartridge in your Sub-Zero refrigerator before you shop:
- Check the existing water filter label — the part number is printed directly on the filter currently installed in the housing. If it shows 4204490, the water filter component of this combo is confirmed
- Check the existing air cartridge label — the part number is printed on the cartridge itself. If it shows 7042798, this is the correct combo pack to order
- Check inside both housing slots — some Sub-Zero models print the required part numbers on labels inside the filter and cartridge housing slots themselves
- Check the refrigerator model plate — the model number is typically located on a label inside the fresh food compartment along the upper door frame or side wall. Use the model number to cross-reference compatibility for both components before purchasing
- Check the refrigerator user guide — the maintenance section lists the correct replacement part numbers for both the water filter and air cartridge for your specific Sub-Zero model
- Search by refrigerator model number — if either label is worn or unreadable, entering your refrigerator model number into the compatibility lookup on the retailer page confirms the correct part numbers for both components before you buy
What Is the Sub-Zero 4204490 Water Filter?
The Sub-Zero 4204490 is an NSF 42 and 53 certified replacement water filter designed for select Sub-Zero refrigerator models. It uses activated carbon block filtration to reduce chlorine taste and odor, lead, heavy metals, VOCs, and sediment before water reaches the dispenser or ice maker. The 4204490 has a service life of 300 gallons or 12 months whichever comes first and uses a twist-in installation design that requires no tools. It is the water filter component shared across both Sub-Zero combo pack variations and is also available to buy as an individual replacement.
What Is the Sub-Zero 7042798 Air Purification Cartridge?
The Sub-Zero 7042798 is a replacement air purification cartridge designed for select newer generation Sub-Zero refrigerator models. It uses activated carbon filtration to continuously reduce food odors and ethylene gas that accelerates produce spoilage inside the refrigerator compartment. The 7042798 uses a snap-in installation design, requires no tools to replace, and carries a recommended replacement interval of 12 months. It is the air cartridge component specific to this combo pack and is not interchangeable with the 7007067 used in the other Sub-Zero combo pack variation. The 7042798 is also available to buy as an individual replacement for households that only need the air cartridge.
What Is the Sub-Zero 7007067 Air Cartridge and Why Does It Matter Here?
The Sub-Zero 7007067 is the air cartridge used in the alternative Sub-Zero combo pack variation paired with the same 4204490 water filter. It performs the same function as the 7042798 but is designed for earlier generation Sub-Zero refrigerator models with a different housing format. If your existing air cartridge shows 7007067 rather than 7042798, the 4204490 and 7007067 combo pack is the correct replacement to order, not this one. Buying the 7042798 combo when your refrigerator requires the 7007067 will result in an air cartridge that does not seat properly in the housing.
Is the 4204490 & 7042798 Combo the Same as the 4204490 & 7007067 Combo?
No. This is the most important distinction to understand before placing your order. Both combo packs include the same 4204490 water filter but they pair it with different air cartridges built for different Sub-Zero refrigerator model generations. The 7042798 fits newer generation models while the 7007067 fits earlier generation models. The two air cartridges are not interchangeable, meaning buying the wrong combo pack results in an air cartridge that either does not seat properly in the housing or leaves gaps that allow unfiltered air to bypass the cartridge entirely. Always confirm the air cartridge part number on the existing cartridge before completing your purchase.
Compatibility Checklist Before You Buy the 4204490 & 7042798 Combo Pack
Run through this checklist before placing your order:
- Does your existing water filter show the part number 4204490? If yes, the water filter component of this combo is confirmed
- Does your existing air cartridge show the part number 7042798? If yes, this is the correct combo pack to buy
- Does your refrigerator model appear on the 4204490 and 7042798 compatibility list? Cross-reference your model number before ordering
- Is your refrigerator from a newer Sub-Zero production generation? The 7042798 is designed for select newer generation Sub-Zero configurations
- Does your existing air cartridge show 7007067 instead of 7042798? If yes, the 4204490 and 7007067 combo pack is the correct replacement to order
- Has it been 12 months or 300 gallons since the last water filter replacement? If yes, it is time to buy a fresh combo pack regardless of whether water taste or refrigerator odor has changed noticeably
Common Mistakes When Buying a Sub-Zero Combo Pack
These are the most frequent ordering errors that lead to compatibility issues and returns:
- Checking only the water filter part number and not the air cartridge — both combo packs share the same 4204490 water filter so confirming only the water filter number is not enough to determine which combo pack is correct for your unit
- Assuming the 7042798 and 7007067 are interchangeable — they are not. Always confirm the air cartridge part number on the existing cartridge before buying
- Buying the combo pack when only one component needs replacing — if only the water filter or only the air cartridge is due for replacement, individual replacements are available to buy separately. The combo pack delivers the best value when both components are due at the same time
- Relying on physical appearance rather than part number — air cartridges from different Sub-Zero generations can look nearly identical but have housing tolerances that differ enough to prevent a proper seal
- Not flushing the water filter after installation — running 2 to 3 gallons through the dispenser after installing the 4204490 clears carbon fines and trapped air and ensures clean water from the first use
- Forgetting to note the installation date for the air cartridge — most Sub-Zero models do not include a dedicated air cartridge indicator light. Writing down the installation date at the time of replacement is the most reliable way to know when to buy your next combo pack
When Should You Order a Replacement Sub-Zero 4204490 & 7042798 Combo Pack?
Order a fresh combo pack when any of the following apply:
- It has been 12 months since the last replacement — this is the primary trigger for buying both the water filter and air cartridge replacement together
- The water filter has reached 300 gallons — households with higher water consumption may reach this mark before the 12 month period is up and should order a replacement water filter at that point
- Dispensed water develops a flat taste or noticeable odor — a sign the 4204490 carbon block is no longer reducing chlorine and contaminants effectively
- Persistent food odors develop inside the refrigerator between cleanings and after removing strongly scented food
- Stored produce is spoiling faster than expected — ethylene gas buildup from an exhausted 7042798 cartridge accelerates ripening in nearby fruits and vegetables
- The filter indicator light activates on the Sub-Zero control panel — order a replacement promptly rather than waiting for taste or odor changes to confirm it is due
Ready to Order the Sub-Zero 4204490 & 7042798 Combo Pack?
If your Sub-Zero refrigerator uses both the 4204490 water filter and the 7042798 air cartridge, you can shop the compatible combo pack replacement and confirm availability here. Buying the combo pack in a single order is the most convenient and cost-effective way to keep both filtration systems performing at full capacity on the same annual cycle.
Shop Sub-Zero 4204490 & 7042798 Combo Pack from purefridgewater.
FAQs
How do I know if my Sub-Zero refrigerator needs the 7042798 or the 7007067 air cartridge before I buy?
Check the part number printed on the existing air cartridge currently installed in your refrigerator. If it shows 7042798, this combo pack is the correct one to order. If it shows 7007067, the 4204490 and 7007067 combo pack is the correct replacement for your unit.
Is buying the combo pack better value than ordering the 4204490 and 7042798 separately?
Yes. Buying the combo pack in a single order is more convenient and cost-effective than purchasing each component separately, especially for households replacing both on the same annual schedule.
Do I need to turn off my Sub-Zero refrigerator before replacing either component in the combo pack?
No. Neither the water filter nor the air cartridge replacement requires the refrigerator to be turned off. The 4204490 twist-in water filter swap does not require the water supply to be shut off on most compatible models, and the 7042798 air cartridge snap-in replacement involves no water connections at all.
Why does my refrigerator still smell after replacing the 7042798 air cartridge from the combo pack?
A new cartridge reduces airborne odor compounds but does not remove odors embedded in refrigerator surfaces or food containers. Wipe down interior surfaces, remove any spoiled food, and allow 24 to 48 hours for the cartridge to reach full adsorption capacity before concluding there is a problem.
How long after buying this combo pack should I plan my next order?
Plan your next purchase at the 12 month mark from the installation date. If your household uses more than 300 gallons of water through the refrigerator dispenser within that period, order a replacement 4204490 water filter at the 300 gallon mark and wait until the 12 month mark to buy the full combo pack again.
Where can I find more detail on the difference between the two Sub-Zero combo pack variations before deciding which to buy?
The Sub-Zero 4204490 and 7042798 combo pack landing page includes a full head to head comparison table covering both combo pack variations side by side to help you confirm the correct one before ordering.