Coffee tastes burnt or overly bitter

Safety: Avoid touching hot surfaces; unplug the unit before internal checks.

• Adjust usage: Do not leave coffee on the hotplate for extended periods. Use the lower hotplate setting if your model has a selector.
• Check brew temperature: Measure brew water temperature as it exits into the basket. If it is significantly above 96°C (205°F), suspect a thermostat issue.
• Inspect thermostats: Remove the base cover and locate both the brew thermostat and hotplate thermostat. Look for signs of overheating or damage.
• Test and replace: Use a multimeter to test thermostat operation. Replace any thermostat that does not open at its rated temperature with the correct Moccamaster part.
• Clean carafe and basket: Coffee oils can contribute to bitter taste. Thoroughly clean the carafe, lid, and brew basket with a coffee-specific cleaner.