Calcium deposits ("scale") from water will build up in the coffee
maker heat pump over time and impair brewing efficiency and
coffee quality. With normal use, scale should be removed every
three months or whenever the water filter icon appears on the brew
timer display. Local water conditions, use of the coffee maker more
than once a day, or use without a water filter may require more
The following conditions indicate an immediate need for descaling:
the presence of loud sounds during brewing
a brewing time greater than 10 minutes for 12 cups of coffee
the appearance of "E1" or "E2" on the brew timer display
Mixing the Descaling Solution
The coffee maker can be descaled using a packaged descaling agent
When using a descaling agent, follow the directions on the
package for the recommended amounts of descaling agent and
water to use.
When using vinegar, mix a solution of 6 cups vinegar and
6 cups water.
Before descaling, always remove the water filter (see "Installing
the Water Filter" on page 13) and make certain the brew basket
contains no coffee or coffee filters.
Run the coffee maker through a complete brewing cycle using
the descaling solution. If the coffee maker has not been descaled
for an extended period, run it through a second brewing cycle
using fresh descaling solution.
Rinse the coffee maker by running it through two brewing cycles
using fresh, cool water.
Wash the brew basket, brew basket insert, carafe, and carafe lid
in hot, soapy water and rinse with hot water. These parts can
also be washed in the upper rack of the dishwasher.
Reinstall the water filter and reset the water filter icon if
necessary (see page 23).
Error Codes During Descaling
If "E1" or "E2" error codes appear during descaling, unplug the
coffee maker for 30 seconds to reset the display, then plug it back
in and continue. If error codes continue to appear after cleaning,
see the KitchenAid Warranty and Service section on page 33.