The short answer
A compact dishwasher that has stopped cleaning properly usually comes down to one thing: the water is not arriving hot enough. Next on the list: the spray arms cannot turn freely. Note the pattern first — whether it is the whole load, one rack, or one kind of item — because that decides which of these it is.
What you observe
- Dishes come out needing to be washed again — Note whether it is the whole load or only part of it.
- Long cycles clean well and short ones do not — Only the heating time is different between them.
- One whole half of the load comes out dirty — A stalled arm washes one sector and abandons the rest.
- A gritty film on glasses and the insides of cups — Debris is being carried back rather than carried away.
- NEAR MISS — dishes are clean but come out wet — That is a drying and rinse-aid question, not a cleaning one, and it belongs on a different page.
Causes, most likely first on this machine
- The water is not arriving hot enough — First where nothing is dissolving properly. Detergent needs heat to work, and a machine that draws its hot water from a distant tank starts every cycle by pushing a length of cold pipe into the tub.
- The spray arms cannot turn freely — Ranked here because it is free to check and because on a tightly-packed machine it happens constantly.
- The filter stack is fouled — Ranked here because it is the cheapest cause, the only one an owner can fully correct, and it is right most of the time.
- The spray arm jets are blocked — Last, and cleared with a cocktail stick in a few minutes.
Check in this order, and why
- Run the hot tap at the sink before starting a cycle — A machine fed from a cold pipe never catches up on a short programme.
- Spin each arm by hand with the racks loaded — An arm that catches is an arm that stops in service.
- Lift the filter stack out and look at what is in it — A dishwasher recirculates its water, so the filter decides what ends up back on the dishes.
- Take each spray arm off and hold it up to the light — A blocked jet always dirties the same part of the load.
What an owner can safely check
- Note exactly what comes out dirty and where it sat — Whole load, one rack, or one kind of item — each points somewhere different.
About 10 min
- Run the kitchen hot tap until it runs hot, then start the machine — Compare the result against a normal start.
About 30 min
- Load the machine as usual, then spin each arm by hand — If it catches anywhere, move the item that caught it.
About 10 min
- Remove the filter stack, rinse it under a hot tap and refit it — Twist it fully home; a filter left loose lets debris past.
Tools: warm water, brushAbout 15 min
- STOP HERE before removing the heater or the wash pump — Those are behind the tub with live terminals nearby. Service call.
Before you open anything
Safety
Switch the machine off at its spur or breaker before removing any panel, and close the isolating valve before touching a hose. A capacitor can hold a charge after the power is off. A countertop or slimline machine is light enough to move and heavy enough to hurt when it is full of water. Drain it before moving it, and keep the faucet adapter clear of a live outlet.
When to call a technician
Call once the filter is clean, the arms turn freely with the racks loaded, the jets are clear and the dose is right, and dishes still come out dirty. At that point it is the wash pump, the heater or the diverter, and all three are behind the tub. Call immediately if the machine trips the breaker, or if there is a burning smell during the wash.
Nearest pages of this class
What this page does not cover
This page is written for the brand and the machine class, not for one family or model line. Where a family- or model-specific page exists for your machine, that page is the more specific answer. Deliberately absent: place settings, adapter and hose part identifiers, cabinet dimensions and wiring colours, which differ between the countertop and slimline built-in families.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
