Water Filter for the GE ZIS420NMA (MWF)

Your GE refrigerator takes the MWF slot. Below is every filter that fits — OEM and certified alternatives — with real prices.

✓ 100% compatible — no bypass plug needed

🔧 5-min push-in swap

🇺🇸 Ships from Indiana

ZIS420NMA · Quick Facts

TYPE

refrigerator

YEARS MADE

—

FILTER LOCATION

in the lower fresh-food zone in most side-by-side layouts, knee height or below

FILTER SLOT

MWF bay

REPLACE EVERY

Every 6 months

ALSO BRANDED AS

—

ZIS420NMA · Quick Facts

Filter locationin the lower fresh-food zone in most side-by-side layouts, knee height or below

Filter slotMWF bay

Replace everyEvery 6 months

Typical installTwist or push — 5 minutes, no tools

Every cartridge that fits this model — pulled live from the catalogue:

✓

Verified fit for ZIS420NMA. Cross-checked against GE service documentation — this model family uses the MWF bay with no chip or bypass restrictions.

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ZIS420NMA specifics — where the filter actually lives

On the ZIS420NMA, the cartridge in the lower fresh-food zone in most side-by-side layouts, knee height or below, a spot that survives trim changes across the ZIS run. This is a twist-style bay, the friendlier design: one twist to release, one to lock; between them you are holding the entire service procedure.

Field notes: a first removal that fights a set o-ring, and a status light that needs a manual hold-to-reset before it acknowledges the new cartridge. ZIS is not a trim code, it is a chassis statement: ZIS is GE’s own coding for Monogram built-in side-by-side machines, and in that format the water path is long enough that a neglected cartridge shows up as flow drop before it shows up as taste. Finish codes such as MA change the look, not the plumbing — order the cartridge by model, ignore the finish letter.

ZIS vs PSS — what the prefix tells you

The ZIS/PSS pair divides this family by layout — Ordering by prefix works because ZIS means Monogram built-in side-by-side and PSS means Profile side-by-side in this catalog — and the cartridge pool overlaps both. The two digits after the letters are the cabinet size: this is a 42 cubic feet refrigerator, which sets how much dispenser work the cartridge does between changes.

Swap it in 5 minutes

Twist the old cartridge a quarter turn counterclockwise and pull it straight down — keep a towel in reach for the dribble.
Fill the new cartridge with cold tap water so the chamber is not fighting an air pocket.
Offer the new cartridge to the bay, push up, and twist a quarter turn clockwise until the stop catches.
Run two gallons through the dispenser to flush carbon fines, then hold the filter-reset control until the status light clears.

What this filter takes out of your water

What it targets	Standard that covers it
Chlorine taste & odor	NSF/ANSI 42 — aesthetic effects
Particulates, Class I	NSF/ANSI 42 — fine sediment
Lead	NSF/ANSI 53 — health effects
Cysts (cryptosporidium, giardia)	NSF/ANSI 53 — microbial
PFOA & PFOS	NSF/ANSI 53 (P473) — varies by cartridge

Coverage above lists what the standard addresses, not a performance claim for any specific cartridge — removal claims vary by certificate, so check the NSF listing for the exact part number you are buying.

ZIS420NMA filter questions

ZIS420NMA filter light will not turn off — what is the reset step?

With the new cartridge seated, press and hold the filter reset until the light clears — panel placement differs, so the ZIS420NMA manual’s filter section has the exact control for your trim.

Can I run the GE ZIS420NMA with no cartridge installed?

No — the MWF bay seals on the cartridge itself, so removing it just means unfiltered water until the next change, not a leak.

Are off-brand filters safe for a GE refrigerator?

Certified aftermarket cartridges are built to the same NSF test standards as the OEM part, and federal warranty law (Magnuson-Moss) protects your coverage when you use them.

Why is the OEM MWF cartridge so much more expensive?

Part of the OEM price is the badge and the distribution chain. Certified alternatives meet the same test standards at a lower unit price, especially in multi-packs.

How often should I replace the filter in my ZIS420NMA?

Every six months or at the rated gallon capacity, whichever comes first — the MWF class cartridges all share that service interval.

Do I need to turn off the water supply to change it?

No — the bay is designed for a live swap. Expect a small dribble, keep a towel in reach, and flush a couple of gallons through the new cartridge before the first glass.

Every filter that fits your fridge

OEM MWF cartridge

This bay takes the OEM MWF. ClearFit verified-fit alternatives for this exact slot are being staged — every compatible option for your fridge is one lookup away.

Check every filter that fits →