DIAGNOSIS This is usually caused by severe limescale buildup inside the internal thermoblock heating system, which drastically reduces heating efficiency.
FIX
- You need to descale the machine. Use Keurig's official descaling solution or a citric acid-based descaler.
- Follow the process precisely: fill reservoir with solution, run multiple brew cycles (large cup size) until reservoir is empty, refill with fresh water, and run cycles again to rinse.
- After descaling, the heat-up time should return to the normal 1-2 minutes.
IF THAT DIDN'T WORK The machine might be in an energy-saving 'sleep' mode. You can disable this: when the machine is on, press and hold the 'Power' button for 3 seconds. The light will change from white to green, indicating it will maintain heat more actively.
HEADS UP If you use the frother for hot milk, that also counts toward the scale buildup. The machine tracks total heating cycles, not just coffee brews, for its internal maintenance timer.