Thermador E23 — Drain pump triac fault — drive circuit failure

What Thermador E23 error means on your dishwasher

Thermador dishwasher error code E23 indicates: Drain pump triac fault — drive circuit failure. This is classified as a High-severity issue — schedule service promptly to prevent further damage.

What E23 means

E23 indicates the electronic drive circuit (triac) that controls the drain pump has failed on the control board. Unlike E24/E25 (physical drain blockages), E23 is an electrical fault — the pump cannot receive power even though it may be mechanically functional.

Effect

The dishwasher cannot drain. Water remains in the tub after every cycle. The drain pump doesn’t run at all, even briefly.

Repair

Control board replacement — the triac is a surface-mounted component that isn’t individually replaceable in the field. Schedule service.

Error E23 quick reference

• Error code: E23
• Appliance type: Thermador Dishwasher
• Severity: High
• Repair type: Needs technician
• Affected components: Control board triac, drain pump, wiring

Troubleshooting Thermador E23 step by step

1. Power reset: Turn off the appliance at the circuit breaker for 5 minutes, then restore power. If E23 clears and doesn’t return, a transient electrical issue caused it.
2. Visual inspection: Check for obvious issues — loose connections, visible damage, water leaks, or unusual sounds from the affected components (Control board triac, drain pump, wiring).
3. Document the error: Note when E23 first appeared, whether it’s constant or intermittent, and any other symptoms (sounds, smells, performance changes).
4. Check related systems: Error codes can sometimes be triggered by adjacent systems — verify that water supply, electrical connections, and ventilation are functioning normally.

Professional diagnosis and repair

If E23 persists after a power reset, professional diagnosis is required. Our certified Thermador technicians use factory diagnostic tools to read stored error history, test individual components (Control board triac, drain pump, wiring), and identify the exact failure point.

Repair typically involves:

• Retrieving and analyzing stored fault codes from the control board
• Component-level testing of the Control board triac, drain pump, wiring
• Replacing failed components with genuine Thermador OEM parts
• Verifying the repair by running a test cycle and confirming the error clears

Preventing Thermador E23 from recurring

While some component failures are age-related and unavoidable, regular maintenance reduces the likelihood of error E23 recurring:

• Follow the maintenance schedule in your Thermador owner’s manual
• Keep the appliance clean — debris and buildup accelerate component wear
• Address minor issues early — small problems left unrepaired often trigger error codes
• Use a surge protector — power fluctuations can damage electronic control boards

For complete specifications and troubleshooting documentation, visit the Thermador official site. To schedule certified Thermador dishwasher repair, Schedule service online — we service all Thermador models in all 50 states with genuine OEM parts and a 30-day labor warranty.