The short answer
Water standing in the bottom of a DWT machine is a blocked or badly routed drain far more often than a failed pump. On a built-in the drain route is hidden behind the cabinet, which is why an installation fault outranks a component fault. Work from the tub outwards and you will find it without tools in most cases. There is one number under the DWT label in the table below, so nothing here depends on which variant you own.
What you observe on these models
- Standing water over the filter at the end of every cycle — The classic built-in finding, and the filter is underneath it.
- The machine hums at the end of the cycle with nothing moving — The pump is running against a block.
- The sink drains slowly at the same time — A shared waste rather than a machine fault.
- It has been getting slower for months — Grease narrowing the line, not a sudden blockage.
- NEAR MISS — the machine will not fill at all — That is a supply fault and belongs on the no-start page.
Causes, most likely first on the DWT family
- The filter and the sump — First on this platform: water standing over a filter packed with debris is the classic finding on any built-in.
- The drain hose high loop, the air gap or a disposer knockout left in place — Second: a hose without a high loop siphons the sink back into the tub; a disposer fitted without its knockout removed blocks the drain completely from day one.
- Control or the water reservoir on models that carry one — Third: where a number fills from its own reservoir, an empty or unseated tank stops the cycle in a way that looks like a drain fault.
- A sink waste shared with the machine — Fourth: where the machine drains into the same trap as the sink, a blocked sink backs up into the machine. The tell is a sink that empties slowly at the same time.
- The machine running a cycle it has not finished — Last: a paused or interrupted programme leaves water in the tub legitimately. Restarting and letting it complete is the first thing to try.
Check in this order, and why that order
- Scoop the standing water out and lift the filter — You cannot judge anything under water, and the filter is under it.
- Check for a high loop in the drain hose or an air gap at the sink — An installation without one siphons the sink back into the tub every time.
- Check the coupler and the tap — A machine that has not filled properly has less to drain than you think.
- Check the tub is not overfilled before the cycle starts — Filling past the line gives water the pump was never meant to clear.
- Run the sink tap and watch whether it drains freely — A shared waste that is blocked explains both machines at once.
Before you open anything
Safety
Unplug the appliance or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off. Treat that as the first step of every check below that involves a panel, a grille or a cover.
Models in the DWT family — The numbers this page covers.
Reference| Model number | Family key |
|---|---|
| DWT18V3S | avanti:dishwasher:dwt |
When to call a technician
Clearing a filter, re-routing a hose and straightening a kink are yours. On these models the line falls at the drain pump, the door switch and the control board. Call without working through anything at all for water arriving from under the machine with every visible joint dry.
Nearest pages of this class
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