Bosch WAT28401UC/06 washer Parts

Yes. The Bosch WAT28401UC washer includes Bosch AquaStop leak protection, which uses a safety water inlet system to help reduce the risk of water damage if the supply hose leaks or the washer detects a leak.

How AquaStop helps protect your home

AquaStop is designed to shut off water flow when a leak condition is detected. On front-load washers like this Bosch model, that protection typically involves the inlet hose and internal leak detection.

Common elements you may see described for AquaStop include:

• A double-walled (sleeved) water inlet hose
• A safety shutoff valve at the water supply connection
• A base pan (floor tray) that can collect water
• A float switch or sensor that triggers shutoff when water is detected

What to check on your specific installation

We recommend confirming the exact AquaStop components and how they’re serviced for your unit in the owner's manual.

Use this quick checklist:

• Verify the washer is connected using the factory water supply hose system
• Make sure the water supply valves fully open and close smoothly
• Check for drips at the hose connections after installation and after moving the washer
• Keep the washer level to help prevent water from sloshing into the base area
• If you see a leak, stop the cycle and unplug the washer before inspecting

Symptoms that can look like an AquaStop event

If the washer stops filling, drains unexpectedly, or shows a fill or leak-related error, AquaStop or leak detection can be involved.

What you notice	What it often points to	What to do next
Washer won’t fill	Water supply issue or safety shutoff triggered	Check valves, hose seating, and error display
Washer drains right after filling	Leak detected or drain hose issue	Inspect for water in the base and verify drain setup
Error code related to fill/drain	Fill, drain, or leak detection condition	Look up the code and follow the steps

For code lookups and next steps, use our Bosch nexxt front load washer error codes.

Why it matters

AquaStop protection helps prevent small hose leaks from becoming major water damage. Keeping the correct hose setup and addressing fill or drain errors quickly helps the system work as intended.

Last updated: February 2026

The most common issues we see with Bosch washers like model WAT28401UC are draining problems (often from a blocked pump filter or drain path) and vibration or banging during spin from an unbalanced load or an unlevel installation. These problems usually have quick checks before any parts replacement. See the troubleshooting section in the owner's manual.

Most common problems (and what they usually mean)

• Washer will not drain or drains slowly: pump filter blocked, drain hose kinked, or drain pipe restricted.
• Excessive vibration or loud banging during spin: load not distributed, washer not level, or floor not solid.
• Too many suds or foam: too much detergent or non-HE detergent.
• Spin canceled at the end of the cycle: unbalanced load detection stopped the spin for safety.

Quick checks we recommend first

1. Redistribute the load: mix small and large items; avoid washing one heavy item alone.
2. Confirm the washer is level: all four feet should press firmly and evenly on the floor.
3. Use HE detergent and reduce the amount: excess suds can extend cycle time and interfere with draining.
4. Check the drain path: inspect the drain hose routing and the home drain/standpipe for restrictions.
5. Clean the pump filter: a blocked pump is a top cause of “won’t drain” symptoms.

Parts that commonly relate to these symptoms

If the basic checks do not resolve draining issues, these model-matched parts are the most relevant starting points:

Symptom	Most likely area	Example part for WAT28401UC
Won’t drain / slow drain	Pump or blockage at filter	Washer drain pump filter 00647920
Hums but won’t drain	Drain pump	Washer drain pump 00145753
Leaks or poor drain routing	Drain hose	Washer drain hose 00656689

Why it matters

Drain and balance problems can look like “major failures,” but they are often caused by detergent choice, a clogged filter, or an installation that is not solid and level. Fixing those basics prevents repeat errors, long cycle times, and water left in the drum.

For code-based symptoms, we use the Bosch nexxt front load washer error codes guide to match the display message to the most likely cause.

Last updated: February 2026

On your Bosch washer, the model number (E-Nr.) is printed on the rating plate label. For WAT28401UC, you will typically find that identification plate inside the appliance door area or on the back of the washer; record the full model number including the slash and final two digits.

Where to look on the washer

Check these common locations first:

• Inside the washer door opening (around the door frame area)
• On the inside of the appliance door area where the identification plate is visible
• On the back panel of the washer
• Near the door boot opening where labels are often placed on front-load washers

What to write down (so parts match correctly)

Bosch uses the E-Nr. as the model number, and it often includes a slash plus two digits (example format: “/27”). Those last two digits matter for correct part matching.

Label item	What it means	Why you need it
E-Nr.	Model number	Ensures parts fit your exact washer version
FD	Serial number	Helps identify production details for service

Tips for reading the rating plate

• Copy the E-Nr. exactly as shown, including the slash and the final two digits
• Take a clear photo of the label before ordering parts
• If the label is worn, check the back of the washer for a second identification plate

Why it matters

Bosch washers can have multiple versions under the same base model name. Using the complete E-Nr. (including the slash and two-digit suffix) helps ensure parts like a drain pump, door boot, or control board match your specific machine.

For the exact label illustration and wording Bosch uses, see the WAT28401UC owner’s manual.

Last updated: March 2026