F21Warning
Bosch Dishwasher F21 Error Code
The dishwasher took too long to drain, often due to a partial clog.
Common causes
- Partially clogged drain hose or filter
- Drain pump running slow or intermittent
- Air gap or high drain loop issues
How to fix it
- Clean the drain filter and check the drain hose for kinks.
- Ensure the drain hose is not too long or elevated incorrectly.
- Check the drain pump impeller for debris.
⚠ When to call a pro: If cleaning does not resolve, the drain pump may need replacement.
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Always unplug the appliance (and turn off the water for washers/dishwashers) before inspecting. These guides are for information only and are not a substitute for a professional repair.