Dometic Toilet: “Cassette tank full”
warning RV toilet warning lights
What it means
On the Saneo control panel, the 'cassette tank full' display lights to show the removable waste cassette has reached its full level and must be emptied. The toilet should not continue to be used until the cassette is emptied to avoid overfilling.
Most likely causes
- Waste cassette is full and needs emptying most likely
- Float in the cassette stuck or jammed by toilet paper giving a false full/level reading common
Safe checks you can do yourself
- Remove and empty the cassette at an approved disposal point.
- If the indicator is wrong, check that the level float in the cassette is free — clean it by hand (never with a high-pressure cleaner, which can damage the float).
- Check the electrical terminals/connections to the level sensor.
How to reset / clear Cassette tank full
- Empty the cassette and reinsert it; the level display updates automatically.
- If still wrong, free the float and recheck the panel.
When to call a technician
The full indicator stays on after the cassette is emptied and the float is confirmed free, indicating a sensor or panel fault.
Applies to
Dometic Saneo CS · Dometic Saneo C · Dometic Saneo B · Dometic Saneo BW/CW/BS/CS/BLP/CLP cassette toilets
FAQ
What does Dometic Toilet code "Cassette tank full" mean?
On the Saneo control panel, the 'cassette tank full' display lights to show the removable waste cassette has reached its full level and must be emptied. The toilet should not continue to be used until the cassette is emptied to avoid overfilling.
How do I reset Dometic Toilet Cassette tank full?
Empty the cassette and reinsert it; the level display updates automatically. If still wrong, free the float and recheck the panel.
What is the most common cause of Cassette tank full on a Dometic Toilet?
The most likely cause is waste cassette is full and needs emptying.
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Sources
- Dometic Saneo Operating Manual — Description of control panel — item 5 'Cassette tank full' display; Troubleshooting — float stuck/jammed remedy (Dometic GmbH)
Note: The Saneo is a cassette toilet with an electric level/flush panel, not a macerating toilet. Included because it is a Dometic electric RV toilet with panel indicator codes.
● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.