Error Code
Thermador Dishwasher E28 Error Code
E28 on a Thermador dishwasher is generally linked to a possible water-drainage problem. This guide gives a plain-language overview, the symptoms you might notice, safe checks you can perform, and when it is best to call a technician — with a reminder that exact behavior varies by model.
Reviewed by Daniel Reeves · Last reviewed August 18, 2026
Error guide
Code overview
Quick answer — E28 — commonly associated with a drainage issue on a Thermador dishwasher. Meaning can vary by model; verify before relying on it.
On many Thermador dishwasher models, the E28 code is commonly associated with a possible water-drainage problem. The exact meaning can differ between appliance series and model years, so treat this as general guidance and confirm it against your specific model’s documentation before acting.
Model note: ASKO reuses codes across series and model years, so E28 may mean something different on another appliance or generation. Confirm against your model’s documentation and record the full model number before acting.
- Error code: E28
- Appliance: Dishwasher
What to look for
Symptoms you may notice
These are the signs homeowners often see when E28 appears on an ASKO appliance.
- The dishwasher stops mid-cycle and shows E28
- Water is left standing in the dishwasher
- Draining seems slow, noisy or incomplete
Why it happens
Possible causes
Exact meaning can vary by model — treat these as common associations, not a final diagnosis.
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A blocked or dirty filter (on models that have one)
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A kinked, clogged or poorly routed drain hose
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A restricted drain pump or drain path
Before you call
Safe checks you can make
Simple, non-hazardous checks only. If anything is unclear, stop and contact a technician.
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Check and clean the accessible filter if your model has one
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Check the visible drain hose for kinks or blockages
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Confirm the drain or standpipe access is clear
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Record the full model number before contacting a technician
Safety first
Important safety warning
Do not open internal panels, access high-voltage wiring, or bypass any safety device. If you see smoke, sparks, a burning smell, or water near electrical parts, switch the appliance off at the outlet if it is safe to do so and call a professional.
Please avoid
What not to attempt
Get help
When to call a technician
If E28 persists after the safe checks above, or you are unsure at any point, book a diagnosis. A technician can confirm what E28 means on your specific model and resolve the underlying cause safely.
Likely related component:
Often related to the drain pump or drain hose (varies by model).
References
Sources & references
- Thermador appliance user manual — error/display messages section
FAQ
Frequently asked questions
Quick answers about E28, safe checks, and when to book a technician.
02 answers
You can safely try the basic checks above and a manufacturer-approved restart. If E28 returns, the underlying cause needs a proper diagnosis. Because the meaning can vary by model, confirm against your documentation.
Not necessarily. Thermador reuses codes across series and model years, and the exact meaning can differ. Record your full model number so the code can be interpreted correctly.
Book a repair
Tell us about your ASKO we’ll take it from there
Share your model and that you are seeing E28 — we’ll confirm an appointment. Prefer to talk? Call us and we’ll help right away.
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