E15
Bosch Dishwasher
Urgency
⚡ Medium
Attend to soon
Repair difficulty
✓ DIY Friendly
No specialist needed
Diagnosis

What this error means

Anti-flood protection activated — the dishwasher has detected water in the base tray and has locked out to prevent flooding.

The E15 error on a Bosch dishwasher means the AquaStop anti-flood system has been triggered. A float switch located in the shallow base tray beneath the machine has detected water and has activated E15 to halt all operation immediately. This is a safety-critical fault. Bosch dishwashers are fitted with the AquaStop system as standard, which automatically closes the inlet valve and locks the machine out the moment the float switch is raised. The most common causes are excessive foam from too much or the wrong type of detergent, a leaking or perished door seal, a loose or cracked internal hose connection, a leaking pump seal, or a cracked outer tub.

Also known as: Same as Siemens and Neff E15

⚠️
For information purposes only. Always consult a qualified engineer before attempting repairs. 🔌 Unplug your appliance before any inspection or repair.
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First steps
Fix time
15–30 minutes
🔧
Difficulty
Anyone
🏠
Appliance
Dishwasher

What you'll need first

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Step-by-step

1
Unplug the dishwasher from the mains immediately
E15 is a safety-critical fault and the machine must be completely de-powered before any investigation is carried out
2
Do not attempt to start any programme or override the lockout
The AquaStop anti-flood system is active and the machine will refuse to operate until the base tray is confirmed completely dry
3
Tilt the machine carefully backwards by approximately 45 degrees with a second person assisting
This drains water from the base tray toward the rear ventilation openings and out onto the floor, resetting the float switch
4
Place old towels behind the machine before tilting to absorb the water that drains out
Allow the base to dry fully and identify the source of the leak before running the machine again
Diagnostic

Symptoms to look for

  1. E15 displayed during or immediately after the start of a programme
  2. Dishwasher locks out completely and will not begin or resume any programme
  3. Water visible on the kitchen floor beneath or in front of the dishwasher
  4. Smell of damp, mildew, or detergent from beneath or around the machine
Step-by-step repair guide

Diagnostic steps

Time 30–60 minutes
Skill Anyone
Unplug and prepare safely

Disconnect the dishwasher from the mains power socket immediately. Water in the machine base is in close proximity to the motor, pump, wiring harness, and control board electronics. Investigating or attempting to operate the machine while powered is a serious electrocution risk.

Do not attempt to tilt or move the machine with it still plugged in. The combination of water in the base and mains power is extremely dangerous. Unplug before doing anything else, without exception.
Drain the base tray by tilting the machine

With the machine fully unplugged and the water supply tap turned off at the wall, open the under-sink cabinet and pull the dishwasher forward enough to access its sides. With a second person assisting, tilt it carefully backwards at approximately 45 degrees and hold this position for 30 to 60 seconds. Water in the base tray will run toward the rear ventilation openings and out onto the floor. Place towels behind the machine beforehand.

Always get help before tilting — undercounter dishwashers are heavy and difficult to control alone. Attempting to tilt one single-handed risks dropping the machine, causing personal injury, or damaging surrounding cabinetry and worktops.
Allow the base to dry completely

After draining by tilting, stand the machine upright and remove the lower front kickplate panel to allow air to circulate into the base tray area. If possible, direct a hair dryer on a cool, low setting into the base for several minutes to speed drying. The AquaStop float switch must be completely dry before E15 will clear and normal operation resumes.

Even a few drops of water remaining on or immediately near the float switch will keep E15 active even after the bulk of the water has been removed. Thorough drying is essential — do not rush this step.
Check the detergent type and quantity first

Excessive foam produced by using too much detergent, using non-dishwasher detergent, or using the wrong tablet format overflows during the wash cycle and drips into the base tray through internal gaps. This is the single most common cause of E15 in otherwise fully functional Bosch dishwashers. Confirm you are using a Bosch-compatible dishwasher detergent and the correct dose for your local water hardness setting.

If E15 appeared shortly after switching to a new detergent brand or format, revert to the previous product and run an empty 65-degree cycle to flush foam residue from the tub seal and base area before returning to normal use.
Run a leak identification test

Once the base is confirmed dry and E15 has cleared, restore power and water and run a Quick Wash programme. Remain present throughout the full cycle. Watch carefully around the door seal perimeter during the wash phase, beneath the machine at kickplate level during the drain phase, and around the soap dispenser door during filling.

Maintain a safe distance during this test. If water appears flowing quickly from beneath the machine at any point, unplug and turn the water supply off immediately before approaching the machine.
Inspect the base tray and AquaStop float switch

With the machine unplugged and tilted or on its back, remove the base cover panel to view the float switch assembly directly. The float arm should be in the lowered resting position with the tray completely dry. Confirm the float arm moves freely up and down with no debris or wiring holding it in the raised (triggered) position.

If the base tray is completely dry and E15 continues to appear after a full reset, the AquaStop float switch itself has failed in the triggered position. Inspect the switch body and its wiring connector and replace if defective.
Did this solve your issue?
Escalation

When to call an engineer

  • Door seal is visibly split, perished, torn, or has holes — must be replaced before the machine is used again
  • Pump seal confirmed leaking — water marks or residue visible around the pump body under the machine
  • Outer tub or base tray has a visible crack or fracture — requires specialist assessment and repair
  • E15 persists with the base tray completely dry after a full reset — AquaStop float switch has failed in the triggered position and must be replaced
Common questions

Frequently asked questions

Is E15 dangerous?
Yes — water inside the machine base is in close proximity to live electrical components including the motor, pump, and control board. Never use or investigate the dishwasher while it is plugged in when E15 is active. Always unplug from the mains first.
Can using too much detergent cause E15 on a Bosch dishwasher?
Yes — this is the most common cause of E15 in machines that have no physical fault. Excessive foam overflows the tub during the wash phase and drips into the base tray, triggering the AquaStop float switch. Reduce the detergent dose and use only products designed for automatic dishwashers.
How do I reset E15 after the base has dried?
Tilt the machine backwards to drain the tray, allow it to dry thoroughly with the kickplate removed, then unplug for 10 minutes and plug back in. E15 will clear automatically once the AquaStop float switch returns to its natural resting position.
Why does E15 keep coming back on my Bosch dishwasher?
Recurring E15 always means a recurring internal leak. Common ongoing causes include a gradually perishing door seal, a worn pump seal, a loose internal hose clamp that vibrates free during cycles, or consistent detergent over-dosing. The source of the leak must be found and permanently fixed.
Dishwasher E 15 code Bosch Neff Siemens - EASY Fix!
Watch time 8 Minutes - From Now FIX IT

This video shows the steps involved to diagnose and fix the E15 Error

Key points covered
  • E15 Causes
  • Seal Cleaning
  • Base removal and Aquastop cleaning

🎯 What is likely causing this fault?

💧
Internal leak (seals, sump, hoses) 45%
💧
Oversudsing / detergent issue (foam leak into base) 30%
⚠️
Tilt/transport water trigger (false activation) 15%
💡
Float switch / wiring fault 10%

⚠️ Estimates based on common faults — not a guaranteed diagnosis. Always verify before ordering parts.

🔩

Parts you may need

Enter your model number to filter results to your exact machine

Usually found on a label inside the door frame or on the back panel of the machine.

No model entered
Part Approx. UK Cost Find it
Door Seal £18 - £30
Sump Seal Kit £10 - £30
Door Seal £15 - £20
Sump Seal Kit £10 - £30

ℹ️ Prices are approximate. Always check the part number matches your model before ordering. Not sure of your model number? Find out how to locate it here.