What this error means
The E23 error code on your Bosch washing machine means the Aquastop anti-flood system has detected a water leak and has shut the machine down to protect your home.
The E23 error is triggered by Bosch's built-in Aquastop flood protection system. A float switch sits in the base tray of the machine — if water leaks into this tray from any internal component, the float rises, triggers the switch, and the machine immediately locks out and displays E23. This is a deliberate safety feature designed to prevent serious water damage to your home. You should not attempt to bypass or ignore this error. Common causes include a split or loose inlet hose, a leaking door seal (drum gasket), a cracked detergent drawer housing, or a leak from the drum, pump, or internal hose connections. The Aquastop hose itself (the blue or grey braided hose connecting the water supply to the machine) also contains its own valve that can trigger if the hose is damaged.
What you'll need first
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Step-by-step
Symptoms to look for
- E23 or Aquastop warning displayed
- Machine stops suddenly and will not restart
- Water visible on the floor around or under the machine
- Machine door locked and will not open
- Damp or wet base tray when machine is tilted
Diagnostic steps
Turn the isolation tap (the tap on the water supply pipe behind or beside the machine) to the closed position. If you cannot find an isolation tap, turn off the mains stopcock for your property. This stops any more water from entering the machine.
Press the power button to turn the machine off, then remove the plug from the wall socket. Do not touch internal components while the machine is plugged in.
The Aquastop hose is the braided hose at the back of the machine that connects your water supply to the machine. Inspect it along its full length for cracks, bulges, or splits. Check that both end connections are tight — one at the tap and one at the back of the machine. The Aquastop hose contains a built-in valve that can trigger E23 if the hose is damaged. If you find damage, replace the hose before using the machine again.
With a helper, carefully tilt the machine to one side or forwards to drain any water that has collected in the plastic base tray. Place towels on the floor first. The float switch that triggered E23 sits in this tray — once the tray is empty, the float will drop and the error should be able to reset.
Open the machine door and run your fingers all the way around the rubber door seal (gasket). Look and feel for tears, splits, holes, or objects such as coins, bra underwires, or broken zip teeth embedded in the rubber. These can cause the seal to leak during a wash cycle. Small tears can sometimes be sealed with a rubber repair kit, but a badly damaged seal should be replaced.
Pull the detergent drawer fully out (press the release tab) and check the housing inside the machine for cracks or lime-scale build-up that could be causing water to overflow into the machine body rather than into the drum. Clean with warm water and descale if necessary.
If you are comfortable doing so, remove the back panel of the machine (three or four screws) and inspect the internal hoses for cracks or loose jubilee clips. Tighten any loose clips. If you are not confident doing this, call a qualified engineer.
Once you are confident the leak source has been found and fixed, plug the machine back in and restore the water supply. Run a short cycle on a low temperature and observe the machine throughout — watch for any drips beneath or behind the machine. If E23 appears again or you can see water leaking, switch off immediately and call an engineer.
When to call an engineer
- Leak source cannot be identified after checking hose, seal, and drawer
- Water is coming from an internal hose or the drum bearings
- E23 returns immediately after reset even with no visible external leak
- Suspected crack in the outer drum or tub
- Water is near or appears to have reached any electrical components
Frequently asked questions
What does E23 mean on a Bosch washing machine?
Is it safe to use my Bosch washing machine when it shows E23?
How do I reset the E23 error on my Bosch washing machine?
What is the Aquastop system on a Bosch washing machine?
Can I fix a Bosch E23 error myself?
🎯 What is most likely causing your Bosch E23 error?
⚠️ 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.
| Part | Approx. UK Cost | Find it |
|---|---|---|
| Aquastop Hose | £10 - £20 | 🏷️ eBay UK → |
| Aquastop Hose | £20 - £25 | 🛒 Amazon UK → |
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.