Bosch Dishwasher Error Code E20
The machine has measured an electrical value in the heat pump that is outside the expected range, covering its heater and motor windings. Independent references describe it as a circulation pump fault, while Bosch groups it with its heat pump heater faults. Either way the heat pump assembly needs testing with a meter, which is technician work.
Common causes
- Open or shorted heater winding in the heat pump
- Failed circulation pump motor winding
- Damaged wiring to the heat pump
- Control board measurement fault
What to check, in order
- Reset power at the breaker for 30 seconds and run a short cycle once.
- Note whether the wash motor runs and whether the water heats, and tell the technician.
- If the code returns, book a service visit; the heat pump needs electrical testing.
Clear the code and test
- Fix what the checks above found first — a filter cleaned, a hose straightened, the spray arms freed. Clearing the code without fixing the cause only brings it back.
- Close the door, plug the dishwasher back in (or restore its breaker) and make sure the water tap is open.
- Run the shortest programme and stay nearby for the first minutes, watching for leaks and listening for the drain pump.
- If the programme finishes with no code, the fault is cleared. If the code returns, write down the code and when it appeared before calling a technician — it speeds up the diagnosis.
When to call a professional
This code usually points to a faulty part, wiring or the control board on a Bosch dishwasher. Run the checks above to rule out the simple causes, then book a technician — and book one straight away if any of these apply:
- The code comes back after you have run the checks and a test cycle.
- You smell burning, see sparks or scorch marks, or the breaker trips.
- Water is leaking and you cannot stop it at the tap.
- The fix needs panels opened beyond what your manual describes, or a part tested with a meter, and you are not set up for that.
When you call, give the brand, the code E20, your model number (on a label inside the door or on the back) and the checks you already ran. It shortens the visit.
Repair or replace?
This fault is in professional territory: the fix usually means a major part or board-level work, and the labour adds up. If your machine is already well into its service life, get the repair quote first, then compare it with the price of a current equivalent model before you decide. Paying a large share of a new machine's price to repair an old one is rarely the better deal; replacing a machine over one cheap fault is wasteful too.
Parts that may be involved
Heat pump (circulation pump with heater)Wiring harnessMain control board
Parts are model-specific. Find your model number first — usually on a label inside the door, on the door frame or on the back — and match the part to that number before ordering.
Questions people ask about E20
What does E20 mean on a Bosch dishwasher?
E20 means: Heat pump electrical fault (heater or pump winding resistance out of range). The machine has measured an electrical value in the heat pump that is outside the expected range, covering its heater and motor windings. Independent references describe it as a circulation pump fault, while Bosch groups it with its heat pump heater faults. Either way the heat pump assembly needs testing with a meter, which is technician work.
Can I fix Bosch E20 myself?
Only the preliminary checks. Code E20 usually means a part, wiring or the control board has failed, which is a technician job. Run the checks to rule out simple causes before you book.
How do I clear Bosch E20?
Fix the cause first — clearing the code on its own brings it straight back. Then restore power and water, run the shortest programme, and watch the stage where the code appeared. If the programme finishes with no code, it is cleared.
Sources checked
- Bosch Home (US) owner support: dishwasher error codes
- Coolblue advice: Bosch and Siemens washing machine errors
The meaning and checks for this code were checked against the sources above in November 2026. Codes vary by model and region; if your manual lists a different meaning for your exact model, follow the manual.