Brewed coffee is very bitter or has a burnt taste.

Safety first: The hot plate can be very hot; avoid touching it directly.

• Reduce keep-warm time: Turn off the hot plate manually after 20–30 minutes or use a lower keep-warm setting if available.
• Use correct grind: For filter coffee makers, use a medium grind, not espresso-fine, to avoid over-extraction.
• Clean carafe and hot plate: Coffee oils burnt onto the carafe or plate can impart a burnt taste. Clean both thoroughly with non-abrasive cleaner.
• Check thermostat (advanced): If the hot plate seems excessively hot or boils the coffee, the thermostat may be faulty and should be replaced.

If bitterness persists with fresh beans and correct grind, the brew temperature control may be out of specification and require service.