The short answer
On a Walsh dishwasher standing water is usually a blocked air gap at the sink, not a failed pump. The pump is the part people replace and the part that is least often at fault. The first two checks need nothing but a cloth and a few minutes.
What you are looking at
- A rattle during the drain phase, then nothing — Something hard has reached the pump impeller.
- Drain water backs up into the sink or the sink backs up into the machine — That is the shared waste, not the appliance.
- NEAR MISS: dishes are dirty but the machine drains — That is a cleaning fault and belongs on the cleaning page for this unit.
What it usually turns out to be, in order
- A blocked air gap at the sink — Where an air gap is fitted on the worktop, it is a small chamber the drain water passes through. Full of soil, it stops the flow and often overflows onto the worktop first. Ranked first on this unit: it is the part of the drain path that is on show and still never cleaned, because most owners do not know what it is, which counts for more here because this is a nameplate you will not find a service bulletin for, so the ranking below is built from the failure modes of the class rather than from a model-specific note.
- The filter and sump packed with debris — Everything the machine washes off ends up here. Next, and for a closely related reason: it is the first restriction in the path, it is reachable without a tool, and on most machines it has never been cleaned.
- A waste disposer knockout plug never removed — A new disposer comes with a sealed inlet spigot. Third: it explains a machine that has never drained properly since the day the kitchen was fitted, and it costs nothing to check.
- A failed drain pump or a stuck check valve — A dead pump makes no noise at all at the drain phase, and a check valve stuck shut gives the same standing water with the pump running normally. Bottom of the list, deliberately: everything above it leaves the same water in the sump and costs nothing to rule out.
Check in this order, and why
- Lift the chrome cover on the worktop fitting and look inside — Debris there stops the machine draining and is trivially cleared.
- Twist out the filter and look into the sump beneath it — A packed filter explains both a slow drain and a total one.
- Ask whether the machine has ever drained properly since installation — A machine that never worked is an installation fault, not a failure.
What an owner can safely check
- Lift the air gap cover, pull the inner cap and clear the chamber — Rinse it through and refit. It takes minutes.
Tools: a clothAbout 15 min
- Bail out the standing water, twist out the filter assembly and clear the sump by hand — Wash the filter under a hot tap and refit it locked home.
Tools: a cup, a cloth, a brushAbout 25 min
- STOP HERE if the next step needs a meter on live terminals — That is where an owner check ends and a service call begins.
Before you open anything
Safety
Switch the dishwasher off at its breaker or unplug it before you put a hand into the sump, and turn the supply valve off under the sink before touching a hose. There is broken glass in a dishwasher sump more often than anyone expects, so use a cloth and work by feel only where you can see. The heating element stays hot long after a cycle ends.
The line between a fix and a service call
Call once the filter, the drain hose, the air gap and the household waste are all clear and the machine still holds water, because at that point the pump or its valve is the fault. Call sooner if the machine trips a breaker, if water is reaching the floor, or if you find glass you cannot safely remove.
Where to go next in this class
Scope of this page, and where to go for more
This page covers the Walsh dishwasher as a class, not one family or model line. Where a family- or model-specific page exists it is linked here. Deliberately not here: pump part numbers, check valve procedures and any wiring detail, all of which differ by family and belong on the page for that family.
Links: - [Water escaping from a Walsh dishwasher, and where it comes from](/blog/walsh-dishwasher-water-leak) - [Walsh refrigerator noise: which sounds matter and which do not](/blog/walsh-refrigerator-abnormal-noise) - [Westbend dishwasher left full of water: what to check first](/blog/westbend-dishwasher-drainage-failure)
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
