Heating up · Keurig K-Duo
Keurig K-Duo: Brew indicator light pulsing slowly on and off
The brewer is heating the water. The first heat takes about 4 minutes; between brews it takes about a minute. The light goes solid when brewing starts.
- Which light
- Main button or power light
- Colour
- Colour not named by the maker
- Steady or flashing
- Fading in and out
What Keurig says to do
- Nothing to do: with Smart Start the brew begins by itself once the water is hot.
From K-Duo Use & Care Guide: Before You Brew, cleansing brews, Brewer Features, Auto Brew, Caring for your carafe and Troubleshooting. This is the K-Duo’s pattern; another Keurig machine may use the same light for something else — check the manual for your model.
Other Keurig K-Duo lights
Heating up on other machines
The same need shows up as a different light on each machine — which is why a light cannot be read without the machine.
Sources
Every line on this page comes from Keurig’s own documents, read on the date shown. Nothing is taken from third-party manual sites.
- Keurig: K-Duo Use & Care Guide: Before You Brew, cleansing brews, Brewer Features, Auto Brew, Caring for your carafe and Troubleshooting — K-Duo single serve and carafe coffee maker (US guide). dam.keurig.com Checked 2026-09-29.