The short answer
On a Unique dishwasher, poor results are almost never a worn-out machine. They are the filter, the spray arms, the water temperature or the way the racks are loaded — and in that order. When a machine may be running on a supply that is not a standard house circuit, the supply itself has to be cleared before any part is suspected.
What you are actually seeing
- Gritty deposits left on the dishes — Recirculated debris, which is the filter.
- Clean on one side of the rack and dirty on the other — A spray arm that cannot turn, or something shadowing it.
- A white film on glassware — Water hardness and rinse aid, not soil.
- NEAR MISS — water standing in the bottom at the end — That is a drainage fault and it has its own page.
Causes, most likely first on this dishwasher
- A blocked filter recirculating debris back onto the dishes — Ranked first on Unique: a fine filter on a bought-in platform fills quickly and there is no warning when it does. On this one, remember that the supply may not be a standard house circuit, so clear the supply before suspecting a part.
- Spray arm holes blocked, or an arm stopped by a tall item — Second: a spray arm that cannot turn leaves a clean stripe and a dirty stripe, and that pattern is the diagnosis.
- The rack is stopping water reaching the soil — Third: a dishwasher cleans by line of sight, so a bowl over a plate leaves both dirty and neither looks like a machine fault.
- Wash pump or diverter not building pressure — Last, and that is the point of the order: it is real, it is uncommon, and every cause above it produces exactly the same dirty dishes for far less money.
Check in this order, and why
- First — lift the filter out and look at it — If it is loaded, nothing else on this list will make any difference until it is clean.
- Then — spin both arms by hand with the racks loaded as you normally load them — Anything they touch is a load fault; blocked holes are a cleaning job.
- Third — look at the dirty items and where they sat in the rack — Dirt in a pattern is loading; dirt everywhere is water, detergent or the filter.
- Only then — only after the filter, the arms, the water temperature and the loading are all cleared — A weak pump cannot be judged with the door shut, so it goes last, which is why it comes after everything above it.
What an owner can safely check
- Wash the filter and clear the sump — Twist it out, brush it under a tap, and scoop out the sump before refitting. Do this monthly from now on.
Tools: brushAbout 20 min
- Clear the spray arm holes and reload anything that fouls them — Take the arms off if they lift out, poke each hole clear with a cocktail stick, and rinse them through.
Tools: cocktail stickAbout 20 min
- Reload so nothing nests and every soiled face points at a spray arm — Bowls angled down, tall items at the sides, nothing lying flat over something else.
About 10 min
- STOP before testing anything electrical with the power on — The checks above are all cold checks. Anything that needs power applied is where an owner check ends.
Before you open anything
Safety
Switch the machine off at its breaker before reaching into the sump — the wash pump can start on a timer. Broken glass hides in a filter and in the sump beneath it, so use a brush and a cloth rather than bare fingers. Never mix a dishwasher detergent with any other cleaning chemical in the tub. Let a finished cycle cool before you reach in, because wash water is hot enough to scald.
When it stops being an owner job
Call when the filter, the spray arms, the water temperature, the loading and the detergent have all been dealt with and the results are still poor. At that point the wash pump, the diverter or the heating circuit is the suspect and all three need the machine open. Call sooner if the machine is also failing to drain, tripping a breaker or leaving the dishes cold at the end of a cycle.
Nearest pages of this class
What this page does not cover
This page is written for the Unique dishwasher as a class, not for one family or one model line. Where a family-specific page exists for your unit it is linked above and it is the more specific answer. Deliberately not here: part numbers, wiring colours, torque figures and any measured value, all of which differ by family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
