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On the WAT models the door seal collects grit and hair at the bottom of its fold, and that is where most leaks start. The tell is a wet floor directly under the door after a wash rather than a puddle that grows all day.
Symptoms on this family
- A slow drip that appears hours after the wash — Usually a fitting weeping under mains pressure rather than a tub leak, which would only show during a cycle.
- Wet wall or skirting behind the machine — That is the inlet side: a tap, a fitting or the hose union rather than anything inside the machine.
- Water only on the drain step — Timing places this at the pump housing, the drain hose or the standpipe connection.
- A puddle under the middle of the cabinet — Hoses, clips and the pump live there, and water travels along the base before appearing, so the exact spot is only a hint.
- Foam and water at the detergent drawer during fill — Overdosing or a blocked drawer housing rather than a machine fault, and it is the easiest of these to fix.
Causes, most likely first on this family
- Inlet hose union weeping at the tap — Under mains pressure all the time, so it leaks between washes as well as during them - a useful distinguishing feature.
- Internal hose clip relaxed with age and vibration — A drum machine shakes its own plumbing loose over years; clips at the sump and the pump are the usual ones to go.
- Drain hose out of the standpipe or clipped badly — Ranks high because a hose that has worked loose empties a full tub onto the floor rather than dripping, which is why it is so dramatic.
- Detergent overdose foaming back through the drawer — Second and the cheapest to fix: the drawer sits above the tub, so foam that backs up has an open route to the floor.
Working the fault in order
- Check the drain hose is clipped and seated at the standpipe — Do this early on any machine that has been moved: a hose out of its pipe is the most dramatic leak and the easiest to miss.
- Dry the floor completely and lay paper towel front, middle and back — The towel that wets first names the region, and that is a far stronger start than guessing from a puddle.
- Pull the machine out and watch a full cycle from behind — Slow and awkward, which is why it is low in the order, but it is the check that finds an internal clip.
- Run the seal fold with a cloth and look for grit and tears — Second because it is the leading cause, and the inspection and the fix are often the same action.
Before you open anything
Safety
Unplug the washer or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off, and on a drum machine the motor control board is the last thing to let go of it.
Models in the WAT family
Reference| Model number | Family key |
|---|---|
| WAT28400UC | bosch:washer:wat |
| WAT28401UC | bosch:washer:wat |
| WAT28402UC | bosch:washer:wat |
When to call a technician
Owner territory ends where the diagnosis needs a meter. If the checks in the order above leave you with a component that can only be tested electrically, that is the point to stop.
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Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
