The short answer
The Blomberg DWS dishwashers are grouped as one platform, and that grouping changes this diagnosis: the same causes apply, in a different order, for reasons of layout. A dishwasher leak is dangerous out of proportion to its size, because the machine sits under a worktop where the water is invisible until it has done damage. Anything behind the kickplate that is not obvious is where the owner side of this ends.
What you observe on these models
- A dark line along the cabinet base beside the machine — Water has been tracking sideways under the kickplate for some time.
- Water on the floor directly in front of the door — The door seal, the door itself, or suds escaping past a seal that is working.
- A damp cabinet side or a swollen worktop edge — A slow leak that has been running long enough to reach the joinery.
- NEAR MISS — the floor is wet but the sink waste is also backing up — A blocked shared waste line puts water on the floor without the dishwasher leaking at all.
Causes, most likely first on this family
- Door seal perished, displaced or fouled — Second: the door gasket runs around the whole opening, takes wear every time the door closes, and traps debris along its lower edge.
- Wrong detergent or too much of it — First on the list because it costs nothing to establish and because it accounts for a startling share of dramatic one-off leaks.
- Pump seal or tub seam failed — Last: a leak from the machine's own structure is the least common and the most expensive, and it is reached only when everything above is clear.
- Why this order is not the brand-generic order — Because the layout differs. On these models the first check is chosen for what it eliminates per minute of work rather than for its standalone probability, and that is what separates a family-level ranking from a brand-level one.
Check in this order, and why
- Establish where the first water appears — Front of the door, under the kickplate, or under the sink. Those three locations have almost no causes in common.
- Watch which part of the cycle produces the water — Fill, wash or drain — each implicates a different connection, and the distinction is free.
- Check the supply fitting with a dry fingertip when the machine is idle — Any dampness there is a pressurised leak and it takes priority over everything else.
- The access logic behind this sequence — Each step above is ordered by how much it rules out per minute spent. On this family that puts the external and audible checks first and anything requiring a panel last, which is the opposite of the order most people work in instinctively.
Before you open anything
Safety
Switch the machine off at its spur or breaker and close the supply valve under the sink before anything comes apart. Standing water in the tub is not the hazard; the heating element and the terminal block under the machine are.
When to call a technician
Call when the filter, the sump, the spray arms and the waste connection have all been checked and the fault has survived all four. Past that point the next suspects are the drain pump and the control, and both of them are behind the machine.
Other faults covered for this family
What this page generalizes over
What this page generalizes over is the set of Blomberg dishwasher models carrying the DWS prefix. They share a platform and therefore a fault pattern; they do not share every part. Anything that varies model by model is deliberately absent, and the pages linked below give both the wider and the narrower view.
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