The short answer for WQP models
When an Avanti WQP dishwasher will not drain, the most useful thing to know is whether the pump is running at all. A machine that hums at the drain step and moves nothing is blocked; a machine that is silent at that step has an electrical or control fault instead.
What the owner sees
- Water draining very slowly rather than not at all — A partial restriction, which points at the filter, the sump or a partly blocked hose.
- Dirty water in the bottom smelling strongly — Water that has sat through several cycles rather than one.
- Water returning into the machine after it has drained — A drain hose with no high loop, so the sink siphons back.
- Standing water in the bottom at the end of the cycle — The defining symptom, and how much is left tells you whether it drained slowly or not at all.
- NEAR MISS — the dishes are dirty but the machine drains — That is a cleaning fault and belongs on that page.
Causes on WQP, most likely first
- Filter and sump packed with food waste — Ranked first because it is the commonest and the only one the owner is asked to maintain.
- Drain pump failed — Less common than any of the above, and the symptom is silence at the drain step rather than a hum.
- Control board not calling for the drain step — The rarest of these and the hardest to confirm without a technician.
- Drain hose kinked behind the machine — Pinched when the machine or a cabinet was last moved, and invisible without pulling the unit out.
What to look at first, second, third
- Before anything else — This order exists because the cheap causes are also the likely ones: two of the four named above can be settled on WQP models before a tool comes out.
- Check the hose rises to a high loop under the worktop — Without it, sink water siphons straight back into the machine.
- Pull the machine out and follow the drain hose for kinks — It gets pinched against the wall or a cabinet foot whenever anything is moved.
- Fill the sink and let it drain — A sink that drains slowly means the household waste is the problem, not the machine.
Before you open anything on this machine
Safety
Switch off at the breaker or unplug, then close the water supply valve. A capacitor can hold a charge after the power is off. On a dishwasher the sharpest hazard is glass: broken fragments collect in the sump under the filter and they are invisible in standing water, so wear a glove and use a torch rather than feeling around.
Models in the WQP family
Reference| Model number | Family key |
|---|---|
| WQP8-7740-US | avanti:dishwasher:wqp |
When to call a technician
Call once the free checks are done and the fault stands: filter cleaned, spray arms cleared, hose proved, waste proved. Call immediately rather than finishing the list if the machine has tripped a breaker, if there is water reaching a socket, or if the leak is continuous with the machine switched off, because that last one is fed at mains pressure.
Other WQP problems we cover
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
