What causes the Descale Light code on a Keurig coffee maker?

Calcium/mineral scale in heater and lines: Hard water deposits accumulate in the internal heating chamber and tubing Use of non-filtered tap water: Untreated water accelerates scale buildup Long interval since last descale: Keurig recommends descaling every 3-6 months or 250 brews

Keurig · Coffee Maker Minor

Descale Light — mineral buildup detected

The Descale indicator illuminates when the brewer detects mineral scale buildup based on brew cycles or flow restriction. It's a maintenance reminder — the brewer will continue to function but performance will degrade until descaled.

Keep using it?: Yes — fix when convenient
DIY difficulty: Easy
Typical cost: $10-15
Verified against: keurig.com ↗

The fix

Keurig Descaling Solution

Mineral scale buildup in the heater and lines (maintenance reminder, not a failure)

$10-15 easy difficulty 45 min

Diagnose first: This is routine maintenance, not a malfunction — the brewer keeps working either way. Adding a water filter cartridge going forward slows how fast scale reaccumulates, especially on hard water.

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Didn't resolve it? Next suspect: Keurig Water Filter Cartridges ($12-20)

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How to fix it

Empty the water reservoir and remove the water filter cartridge if installed
Pour a full bottle of Keurig Descaling Solution (or 14 oz white vinegar) into the reservoir
Add an equal amount of fresh water to fill the reservoir
Without a K-Cup, run repeated brew cycles into a large mug, discarding the liquid, until 'Add Water' appears
Let the brewer sit for 30 minutes powered on
Empty and rinse the reservoir thoroughly, refill with fresh water
Run at least 12 cleansing brews with fresh water to flush
On K-Supreme/K-Elite models, hold the 8oz and 12oz buttons together for 3 seconds to reset the descale light

Why it happens

Typical signs: Descale light glows steady · Slower brew times · Smaller cup volumes than selected · White flakes in cup · Light remains on after brewing

Calcium/mineral scale in heater and lines Hard water deposits accumulate in the internal heating chamber and tubing
Use of non-filtered tap water Untreated water accelerates scale buildup
Long interval since last descale Keurig recommends descaling every 3-6 months or 250 brews

More Keurig coffee maker codes

Add Water Add Water Light — reservoir low or sensor fault All Lights Blinking All Lights Blinking — internal water flow or sensor fault Auto Off Auto Off — power-save shutdown Brewer Needs Reset Brewer Needs Reset — control board lockup Brew Interrupted Brew Interrupted — cycle aborted mid-brew Drip Tray Full Drip Tray Full — empty drip tray

All Keurig codes → All coffee maker codes →

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: keurig.com.