Bosch Washing Machine Error Code F23

Reviewed by the ApplianceErrors Editorial Team · Verified against manufacturer service documentation · Last verified: July 19, 2026

⚠ High Severity 🔧🔧 Moderate DIY Also shown as: E23

Leak sensor activated — AquaStop or flood-protection sensor triggered

The most common cause of the F23 error on a Bosch washing machine is door seal/boot damaged or detached (~30% of cases); start with: tilt the machine to drain the base.

💰 DIY cost: $0–$100 👨‍🔧 Pro cost: $150–$380 Save $150+ by doing it yourself

Bosch Washing Machine error code F23 on the display panel — How the F23 code appears on a Bosch washing machine display

What Does Error Code F23 Mean on a Bosch Washing Machine?

Leak sensor activated — AquaStop or flood-protection sensor triggered.

F23 fires when the polystyrene float in the base tray rises far enough to trip the flood-protection microswitch, telling the control board water has collected under the tub. The machine halts and typically runs the drain pump continuously to prevent overflow. Unlike drain faults (F03) or fill/valve faults, F23 specifically signals standing water in the base — not a slow drain — so it persists until the tray is emptied and the leak source is corrected.

Models affected: Bosch front-load washers equipped with AquaStop or base-tray flood protection, including models such as WAT28400UC and WGA12400UC

What owners report: Owners commonly report F23 appearing mid-cycle or when starting after the machine has sat unused, and it can be falsely triggered by condensation or a minor spill that pools in the tray. A frequent quick win is tilting the unit to drain the base and letting it dry overnight before restoring power, though a persistent code usually points to an actual weeping hose or seal.

What Causes Error Code F23?

Here are the most common causes in order of frequency. Start with the most likely cause before moving to the next:

1

Door seal/boot damaged or detached 30% of cases
2

Supply hose fitting weeping 25% of cases
3

Internal hose connection loose 25% of cases
4

Base-tray float sensor triggered by condensation or spill 20% of cases

How to Fix Bosch Washing Machine Error Code F23

🔧🔧 Moderate DIY Est. time: 30–60 min

⚡ Safety first: Unplug the appliance before opening any panels or touching internal components.

1

Tilt the machine to drain the base

Power off and carefully tilt the machine forward to drain water from the base tray.

⚠️ Turn off water and power before tilting.
2

Inspect the door seal

Check the rubber boot gasket for tears or detachment.

🔩 Bosch washer door seal ($30–$75)
3

Check supply hose connections

Inspect both ends of the fill hose for any weeping.
4

Inspect internal hoses

After the base is dry, access the back and check internal hose connections.

How to Reset Error Code F23

Drain the base, find and fix the leak source, allow to dry, then reset by restoring power.

Note: If the error returns after resetting, the underlying issue has not been resolved. Work through the fix steps above.

Full Bosch washer reset guide → Enter diagnostic mode → Symptom guide: Washer leaking water →

Did this guide fix your appliance?

When to Call a Professional

If no external leak is visible after draining and drying, a pump seal or internal fitting is leaking — professional inspection needed.

Average professional repair cost for this issue: $150–$380

Related Error Codes

E04

Anti-flood device activated — water detected in base

⚠ High Severity

F03

Drain timeout — water did not drain within the expected time

⚠ High Severity

Same Code on Other Brands

Error code F23 appears on these other brands too. See every brand that shows F23 →

Whirlpool Dryer F23

Outlet thermistor failure (short circuit)

Kenmore Dryer F23

Outlet thermistor failure — reading shorted

Maytag Dryer F23

Exhaust thermistor short circuit

Find Replacement Parts

Use these links to find the exact replacement parts for your Bosch Washing Machine:

🔩

Search PartSelect

Bosch Washing Machine repair parts

🔧

Search RepairClinic

Step-by-step video guides

External links — ApplianceErrors.com is not affiliated with these retailers.

More Bosch Washing Machine Error Codes

E18 Drain time exceeded — water not draining within expected time E02 Door lock failure — cannot lock door for cycle E17 Water intake fault — fill time exceeded F01 Water intake timeout — machine failed to fill within the expected time F02 Heating timeout — water did not reach the target temperature F04 Motor fault — drive motor not running correctly

Frequently Asked Questions

Can I keep using my Bosch Washing Machine when error F23 appears? +

It is not advisable. The washing machine may still power on, but running it while F23 is active can worsen the leak fault or damage related parts. Treat it as a soon-as-possible repair.

What most commonly causes F23 on a Bosch Washing Machine? +

Across reported Bosch washing machine repairs, the most frequent is door seal/boot damaged or detached (30% of cases), supply hose fitting weeping (25%), then internal hose connection loose (25%). Check them in that order before replacing any parts.

F23 keeps coming back after a reset — what should I check next? +

A reset only clears the stored F23 fault; if it returns, the leak problem is still present. Move on to the physical checks — tilt the machine to drain the base, then inspect the door seal — since the code will reappear until the root cause is resolved. This is a moderate job — a multimeter and some disassembly are usually involved.

How much does it cost to fix Bosch Washing Machine error F23? +

A DIY repair typically runs $0–$100 in parts, versus $150–$380 for a professional service call, so handling it yourself saves around $150. Expect the work to take roughly 30–60 minutes.

Which Bosch Washing Machine models show error F23? +

F23 is documented on Bosch front-load washers equipped with AquaStop or base-tray flood protection, including models such as WAT28400UC and WGA12400UC. Other units sharing the same control platform can display it too, so the fixes here generally transfer across the series.

Sources & References

• Bosch Home Appliances Service — official manufacturer documentation
• Our editorial & verification policy

Content verified against manufacturer service documentation. Last verified: July 19, 2026.

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