What Does F84 Mean?
The F84 error code on your Miele dishwasher indicates a heating system malfunction. Your dishwasher's control board has detected that the water temperature is not reaching the expected level, or the heating element is not responding correctly.
This is a medium severity error. While it won't cause immediate damage to your appliance or home, continuing to use the dishwasher will result in poorly cleaned dishes and potential hygiene concerns.
Why Proper Heating Matters
Your Miele dishwasher heats water to specific temperatures for important reasons:
- 55-65°C (Main Wash): Dissolves grease and breaks down food particles
- 65-75°C (Final Rinse): Sanitizes dishes by killing bacteria
- Drying Phase: Hot rinse water aids in drying
When the heating system fails, none of these functions work properly, leaving you with dishes that look clean but may harbor bacteria.
Models Commonly Affected
The F84 error can appear on most Miele dishwasher models, including:
- G 4000 / G 5000 / G 6000 / G 7000 series
- Older G 800 / G 900 series
- Built-in and freestanding models
The diagnostic process is similar across models, though part numbers may vary.