The short answer
Water left in the bottom of a dishwasher is a blockage far more often than a failed pump, and most of the blockage is within reach: the filter, the drain hose and the disposal connection under the sink. The pump is the last thing to suspect, not the first. On a RecPro dishwasher the cause that ranks first is drain hose kinked or without its high loop.
What you observe
- Standing water in the sump at the end of every cycle — The classic blockage picture: filter, hose or waste connection.
- The pump audibly runs but nothing leaves — A restriction downstream of the pump rather than a pump failure.
- NEAR MISS — water appears only when the sink is used — That is a backflow problem from the waste, not a drainage failure of the machine.
Causes, most likely first on a RecPro dishwasher
- Drain hose kinked or without its high loop — A hose crushed behind the machine blocks it; a hose that never rises above the machine lets waste water run back in. Ranked first on this dishwasher, because the hose is fitted once at installation and then never looked at again.
- Filter and sump loaded with soil — The filter fills, then the coarse screen behind it, and flow falls away until the cycle cannot clear the sump.
- Air gap blocked or disposal knockout plug still in — A new disposal is supplied with its dishwasher inlet plugged, and fitting one without removing that plug blocks the dishwasher completely.
- Debris in the sump or check valve — Glass, seeds, labels and bone fragments lodge at the check valve and hold it open or shut.
Check in this order, and why
- Open the cabinet beside the machine and look at how the hose runs — A hose with no rise above the machine will siphon back every time.
- Bail the sump, take the filter out and look at it — It is the first step because it is free and it is usually the answer.
- Ask whether any work has been done under the sink — A new disposal with its plug in place blocks the machine completely.
What an owner can safely check
- Open the adjacent cabinet, straighten the hose and secure it so it rises above the machine before falling — A hose clipped high under the worktop is what stops waste water returning.
Tools: torch, screwdriverAbout 25 min
- Bail the sump out with a cup, then remove and wash the filter and the screen behind it — Refit it locked home; a filter that is not seated lets soil straight past.
Tools: cup, towels, soft brushAbout 25 min
- Check the disposal inlet plug has been removed and clean the air gap cap if there is one — The plug is a moulded disc inside the disposal inlet and must be knocked out before connecting.
Tools: torchAbout 20 min
- STOP HERE if the next step needs a meter on live terminals or a panel off — That is where an owner check ends and a service call begins, whatever the ranking above says.
Before you open anything
Safety
Switch the machine off at its breaker or unplug it before reaching into the sump or opening the cabinet beside it — a capacitor can hold a charge after the power is off. Water in the sump after a cycle can still be hot; let it stand. Wear a glove when clearing the sump, because broken glass collects at the check valve. Never run a disposal while your hand is anywhere in the sink waste, and shut the water off under the sink before disturbing any joint.
When to call a technician
Call when the filter, the hose run, the disposal connection and the sump are all clear and water still stands, because what remains is the pump or its control. Call a plumber instead if the sink backs up while the machine drains: the shared waste is restricted and the dishwasher is only reporting it. Do not keep running cycles on a machine that will not drain, because each one adds hot, dirty water with nowhere to go.
Nearest pages of this class
What this page does not cover
This page is written for the RecPro dishwasher as a class, not for one family or model line. Where a family- or model-specific page exists for your unit it is linked above, it is the more specific answer, and it is the one to read first. Deliberately not here: part numbers, wiring colours, panel removal order and torque figures, which differ between families under the same nameplate.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
