How to Flush a New Refrigerator Water Filter (And Why It Matters)
How to Flush a New Refrigerator Water Filter (And Why It Matters)
Flushing a new refrigerator water filter is the one step most people skip — and it is the step that explains why your first glass of water from a new filter looks grey, tastes odd, or leaves residue in your glass.
Every new activated carbon block filter contains fine loose carbon particles that are dislodged during shipping and initial water contact. Flushing removes them before you drink. It is harmless, takes 5 minutes, and is required for every filter brand regardless of OEM or compatible.
Run the water dispenser continuously for 4–6 minutes, discarding all the water that comes out. Expect grey or cloudy water for the first 1–2 minutes. Continue until the water runs completely clear. Do not drink or use the first 2–3 gallons from a new filter.
Why New Filters Need Flushing — The Science
Activated carbon filters are manufactured by heating coconut shell or coal to extremely high temperatures in the absence of oxygen, creating a porous carbon structure with a surface area of up to 2,000 square metres per gram. During this process and subsequent packaging, fine carbon dust particles settle throughout the filter media.
When water first passes through the new filter, it carries these loose particles out with it — producing grey, cloudy, or black-tinged water. This is completely harmless (activated carbon is used in water purification and in medical treatments for poisoning), but aesthetically unpleasant and unnecessary to drink. Flushing clears these particles out before the filter is used for drinking water.
Step-by-Step: How to Flush Your New Refrigerator Filter
Confirm the Filter Is Correctly Installed
Before flushing, confirm the new filter is fully seated and locked — fully rotated clockwise (twist-type) or fully clicked in (push-type). The protective O-ring cap must be removed. A partially seated filter will drip during flushing.
Place a Container Under the Dispenser
Use a large jug, bucket, or bowl to collect the flush water. You will be running approximately 2–3 gallons through the dispenser — having a container ready makes the process faster and less wasteful.
💡 Don’t waste it — use flush water for house plants, mopping floors, or watering the garden. It is perfectly safe for non-drinking uses.Dispense Continuously for 4–6 Minutes
Hold the dispenser lever down continuously. Do not pause between glasses — continuous flow is more effective than repeated start-stop cycles at clearing carbon particles from the media. Expect the first minute to produce grey or milky water.
Confirm Water Is Clear
Fill a clear glass and hold it up to light. The water should be completely clear with no grey tinge, cloudiness, or particles. If still slightly cloudy after 6 minutes, run another 2 minutes and check again.
Discard the First Ice Batch
If your refrigerator has an ice maker, the ice maker will fill using the same unflused water. After flushing the dispenser, also discard the first full ice maker cycle — usually 1–2 trays of ice. This ensures your first ice is made from fully flushed filtered water.
Flushing by Brand — How Long Each Takes
| Brand | Recommended Flush Volume | Approximate Flush Time | Common Flush Note |
|---|---|---|---|
| LG | 2–3 gallons | 4–6 minutes | LT1000P / LT700P flush relatively quickly |
| Samsung | 2–3 gallons | 4–6 minutes | DA29-00020B may take 7+ minutes in hard water areas |
| Whirlpool | 2–3 gallons | 4–6 minutes | EveryDrop filters flush cleanly within 5 minutes |
| GE | 3 gallons | 5–7 minutes | RPWFE benefits from a longer flush — higher carbon density |
| Maytag / KitchenAid | 2–3 gallons | 4–6 minutes | UKF8001 flushes similarly to W10295370A |
| Frigidaire | 2 gallons | 3–5 minutes | Usually clears quickly — smaller filter body |
If water is still cloudy after a 10-minute continuous flush, stop and check: (1) Is the filter fully locked? A partial seat allows unfiltered water to bypass the media. (2) Is the protective O-ring cap removed? (3) Is this the correct filter model for your fridge? Contact our support team — persistent cloudiness after thorough flushing may indicate a filter issue covered by our Guaranteed Fit Promise.
Frequently Asked Questions
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