Thermador Dishwasher Error Codes: Complete Guide for All Series

Thermador dishwashers — spanning the Emerald, Sapphire, and Star Sapphire series — are built on the BSH platform shared with Bosch, but with premium upgrades like the Star Speed wash system, CrystalDry with zeolite technology, and ultra-quiet operation (as low as 39 dBA on Star Sapphire models). When an error occurs, these units communicate through E-codes displayed on the panel or reported through the Home Connect app.

Understanding Thermador dishwasher error codes is critical because these machines cost $1,500–$3,500, and misdiagnosis can lead to unnecessary part replacements at premium BSH pricing.

How Thermador Dishwasher Errors Display

Thermador dishwashers show errors in two ways:

1. LCD panel models (Sapphire/Star Sapphire): Alphanumeric code appears directly on the display (e.g., "E15" or "E24").
2. LED indicator models (Emerald): Error indicated by a combination of blinking LEDs — typically the Clean and Drain lights flash in a specific pattern.

To reset: Press and hold the Start button for 3 seconds to cancel the current cycle. If the error persists, turn off the circuit breaker for 60 seconds. On Home Connect models, you can also clear non-critical errors through the app.

E15 — Water in Base Pan (Anti-Flood Activated)

E15 is the most common Thermador/BSH dishwasher error. The float switch in the base pan has detected water, triggering the anti-flood safety system. The drain pump will run continuously to evacuate the water.

Common causes:

• Loose or cracked hose connection inside the unit (spray arm hose, sump-to-pump hose)
• Failed door seal allowing water to seep into the base during wash cycles
• Cracked sump or wash tub housing
• Water inlet valve stuck open, overfilling the tub
• Blocked drain causing water to back up and overflow the tub into the base

Troubleshooting steps:

1. Turn off power at the breaker. Pull the dishwasher out from the cabinet (disconnect water supply and drain hose first).
2. Tilt the unit backward approximately 45 degrees to drain water from the base pan. Have towels ready.
3. Remove the base pan cover and inspect for the water source. Look for wet spots on hoses, the door seal area, and the sump housing.
4. The most common failure on Thermador models: the spray arm hose connection at the sump loosens over time from water pressure cycles. Check all hose clamps.
5. Dry the base pan completely and lower the unit. The float switch must drop to its resting position before the error clears.
6. Restore power and run a short cycle while monitoring for leaks.

Repair cost: $200–$500. Hose replacement is affordable; sump or tub housing cracks require $400+ in parts for Thermador-grade components.

E24 — Drain Error

The dishwasher cannot drain water from the tub within the expected time (typically 4 minutes). Water remains in the bottom of the tub after a cycle.

Common causes:

• Clogged drain filter at the bottom of the tub
• Kinked or obstructed drain hose under the sink
• Garbage disposal knockout plug not removed (on new installations)
• Failed drain pump motor (BSH part 00631200)
• Air gap or high loop issue in the drain hose routing
• Food debris blocking the drain pump impeller

Troubleshooting steps:

1. Remove and clean the drain filter assembly at the bottom of the tub — twist counterclockwise to remove. Rinse under running water and scrub with a toothbrush.
2. Check the drain hose under the sink for kinks, particularly at the garbage disposal or P-trap connection.
3. If connected to a garbage disposal, verify the knockout plug was punched out during installation. This is the most commonly missed installation step.
4. Inspect the drain pump impeller through the filter opening — use a flashlight to look for glass, bones, or other debris.
5. Test the drain pump: in diagnostic mode, activate the drain function. If the pump hums but water does not flow, the impeller is likely broken.

Repair cost: $0 (if just a clogged filter or kinked hose) to $250–$400 for drain pump replacement. Thermador drain pumps are BSH-standard parts, moderately priced compared to other Thermador components.

E01 — Water Inlet Failure

The dishwasher is not receiving water or is filling too slowly. The cycle cannot begin without adequate water in the tub.

Common causes:

• Water supply valve under the sink turned off or not fully open
• Clogged inlet valve filter screen (mineral deposits from Sacramento's hard water)
• Failed water inlet valve solenoid (BSH part 00637572)
• Aquastop safety valve activated (models with the Aquastop hose system)
• Low household water pressure (below 20 PSI)

Troubleshooting steps:

1. Verify the water supply valve under the sink is fully open.
2. Check for the Aquastop safety hose — if the indicator window shows red, the Aquastop has been triggered by a detected leak. The entire Aquastop hose assembly must be replaced.
3. Disconnect the water supply line at the inlet valve and inspect the screen filter. Hard water deposits are extremely common in the Sacramento and Bay Area. Clean with white vinegar and a toothbrush.
4. Test water pressure at the supply line — run water into a bucket and measure flow rate. The dishwasher needs at least 1 gallon per minute.
5. Test the inlet valve solenoid with a multimeter — coil resistance should be 500–1,500 ohms.

Repair cost: $100–$300. Screen cleaning is a basic service call. Aquastop hose replacement is $150–$200 for the genuine BSH part.

E09 — Heating Element / Water Temperature Error

The water has not reached the target temperature within the expected time. Thermador dishwashers heat water to 150–165F for optimal sanitization performance.

Common causes:

• Failed flow-through heater (BSH part 00648669)
• NTC temperature sensor reading incorrectly
• Relay failure on the control board (heater circuit)
• Incoming water temperature too cold (below 100F)
• CrystalDry zeolite system interference (on Star Sapphire models)

Troubleshooting steps:

1. Run your kitchen hot water faucet until it reaches maximum temperature before starting the dishwasher. The dishwasher heater is supplemental — it expects incoming water of at least 120F.
2. Access the heater element in the sump area (requires removing the base panel). The BSH flow-through heater is an inline element that water passes through, not a traditional submerged element.
3. Test the heater for continuity — resistance should be 10–15 ohms. An open reading means the element has burned out.
4. Check the NTC sensor: at room temperature, approximately 50,000 ohms (50kΩ). The sensor is integrated into the sump housing on newer models.
5. On Star Sapphire models with CrystalDry, ensure the zeolite container is properly seated — a misaligned container can trigger false temperature readings.

Repair cost: $300–$600. The BSH flow-through heater assembly is a premium component, and access requires significant disassembly.

E22 — Turbidity Sensor / Water Clarity Error

The optical turbidity sensor cannot get an accurate reading of water clarity, preventing the sensor-driven wash optimization from functioning.

Common causes:

• Sensor lens coated with grease film or hard water scale
• Failed turbidity sensor (optical emitter/receiver)
• Wiring harness damage between sensor and control board
• Excessive food debris in the wash water preventing any clarity reading

Troubleshooting steps:

1. Clean the turbidity sensor lens — located in the sump area near the drain filter. Use a soft cloth with white vinegar to dissolve hard water deposits and grease film.
2. Run an empty cycle with dishwasher cleaner (affresh or similar) to remove interior grease buildup that may be contaminating the sensor.
3. If cleaning does not resolve E22, access the sensor connector and check for corrosion or loose pins.
4. The sensor uses an infrared LED and photodiode pair — if either component fails, the entire sensor must be replaced.

Repair cost: $150–$300. Cleaning resolves most cases. Sensor replacement is moderate due to sump area access requirements.

E04 — Flow Sensor Error

The flow sensor that monitors water circulation through the wash arms is not detecting adequate flow, indicating a possible pump or circulation problem.

Common causes:

• Blocked spray arm jets (food particles, hard water deposits)
• Failed wash pump motor (BSH part 00239144)
• Obstructed circulation path (utensil fallen through the rack blocking the spray arm)
• Flow sensor malfunction (stuck or corroded turbine wheel)
• Air lock in the wash pump after a recent installation or drain error

Troubleshooting steps:

1. Remove both spray arms and clean all jets — use a toothpick or straightened paper clip to clear each hole. Hard water deposits frequently block the fine jets on Thermador's precision spray arms.
2. Check inside the tub for any objects that may have fallen and blocked the spray arm rotation.
3. Inspect the flow sensor (small turbine device in the circulation path) for debris blocking rotation.
4. Prime the wash pump: fill the tub manually with 1 quart of water and run a short cycle. An air lock after E24/drain events can prevent the pump from priming.
5. If the wash pump motor is failed, it will hum without circulating water. Replacement requires sump disassembly.

Repair cost: $200–$500. Spray arm cleaning is a basic service call. Wash pump replacement is labor-intensive due to sump access.

Home Connect Diagnostics for Thermador Dishwashers

The Home Connect app provides enhanced troubleshooting capabilities:

Remote cycle monitoring: Track cycle progress, time remaining, and receive completion notifications.

Error history and pattern analysis: The app logs all error events, helping identify intermittent issues like E15 water leaks that only occur during specific cycle phases.

Service scheduling: When an error occurs, the app can directly connect you with certified BSH service providers and share the diagnostic data automatically.

Cycle optimization: If you receive E09 temperature errors, the app shows whether the issue is consistent or intermittent, helping technicians diagnose whether the heater is failing completely or has a thermal intermittent.

Star Sapphire Specific Notes

The Star Sapphire series (DWHD870WFP and similar) includes additional components that generate unique error states:

• CrystalDry zeolite system: The zeolite mineral absorbs moisture during the drying phase and releases heat. If the zeolite container is not seated properly or the regeneration heater fails, you may see E09 or a specific CrystalDry error.
• Star Speed cycle: The accelerated 20-minute wash uses higher water pressure. If the pump cannot achieve the required pressure, the unit will show E04 during Star Speed but work fine on normal cycles.
• AutoAir door opening: The automatic door-pop feature at end of cycle uses a spring mechanism. Failure does not generate an error code but the door will not open automatically.

Frequently Asked Questions

Q: Why does my Thermador dishwasher keep showing E15 even after I dried the base? A: The float switch in the base pan is extremely sensitive — even a tablespoon of residual water can keep it triggered. After tilting and toweling the base, use a wet-dry vacuum to extract all remaining water. Also check that the float itself moves freely (not stuck in the up position from detergent residue). Some technicians apply a light silicone spray to the float guide.

Q: How do I access diagnostic mode on my Thermador dishwasher? A: On LCD-panel models, press and hold the two buttons directly left and right of the Start button simultaneously for 5 seconds. On Emerald LED models, close the door and press the Power Scrub and Regular Wash buttons in an alternating pattern 3 times within 5 seconds. The service manual for your specific model has the exact combination.

Q: Is E24 an emergency or can I continue using my dishwasher? A: E24 (drain error) is not an immediate emergency, but running additional cycles without resolving it can cause E15 (water overflow into the base) which can damage the motor and control board. Resolve E24 within 1–2 days. In the meantime, you can manually drain the tub using the emergency drain (pull the drain hose down to a pan on the floor — gravity drain).

Q: My Thermador dishwasher shows no error code but does not clean well. What should I check? A: On BSH dishwashers, subpar cleaning without an error code usually means: (1) spray arm jets are partially blocked by hard water deposits — remove and soak in vinegar, (2) the turbidity sensor is dirty — causing the dishwasher to think water is clean too early, (3) incoming water temperature is too low — run hot water at the sink before starting. Check these before calling service.

Q: How much does Thermador dishwasher repair cost compared to Bosch? A: Thermador and Bosch share the same BSH mechanical platform, so many internal components are identical. However, Thermador's premium trim pieces, panel-ready components, and Star Sapphire-specific parts (like the CrystalDry zeolite assembly) are more expensive. Expect Thermador repairs to run $400–$800 for major issues vs. $250–$500 for equivalent Bosch repairs.

Expert Thermador Dishwasher Repair from EasyBear

Thermador dishwashers demand BSH-trained technicians who understand the shared Bosch engineering plus the premium Thermador-specific systems. EasyBear's repair specialists service all Thermador series — Emerald, Sapphire, and Star Sapphire — with access to genuine BSH replacement parts. We offer a free diagnostic visit where our technician uses BSH diagnostic tools to identify the exact failure point, provides transparent pricing, and in most cases completes the repair same-day. Every repair carries our 90-day parts and labor warranty.