DishwasherNot Cleaning?
It runs a full cycle and the dishes come out worse than they went in. The good news: a majority of “not cleaning” complaints aren’t a broken dishwasher at all. The bad news: the fixes people try first usually aren’t the ones that work.
What's probably wrong
Ranked by how often this kind of fault turns out to be each one. A list isn’t a diagnosis — that takes someone looking at your specific machine — but it’s worth knowing what’s on the menu before anyone quotes you.
Nearly every dishwasher built in the last fifteen years has a removable filter in the floor of the tub, and a large share of owners have never taken it out. Once it loads up, the machine recirculates dirty water over clean dishes. Symptom: gritty residue, and often a smell. Pull it, rinse it under the tap, put it back.
The most common causes
Ranked by how often we see each one. The diagnostic that actually matters isn't a guess from a list — it's a tech listening to your machine, looking at the install, and checking the right things in the right order. But it's useful to know what's on the menu.
Clogged Filter
Nearly every dishwasher built in the last fifteen years has a removable filter in the floor of the tub, and a large share of owners have never taken it out. Once it loads up, the machine recirculates dirty water over clean dishes. Symptom: gritty residue, and often a smell. Pull it, rinse it under the tap, put it back.
Blocked Spray Arm Jets
The arms spin and fire water through small holes. Those holes plug with scale, seeds, labels and grit. Partially blocked arms produce the classic pattern where one rack cleans fine and another doesn’t. Holding the arms up to the light shows it immediately.
Water Arriving Too Cool
Dishwasher detergent needs genuinely hot water to dissolve and activate — roughly 49°C at the machine. If the tank is set low, or the dishwasher sits far from it on a long pipe run, the first fill arrives cool and the cycle never recovers. Very common, almost never suspected.
Scale Buildup on Elements and Arms
Hard water leaves mineral deposits on the heating element, spray arms and tub walls. Scale insulates the element so water heats more slowly, and narrows the jets so pressure drops. It accumulates over years, so the decline is gradual enough that people adjust to it without noticing.
Worn Wash Pump or Impeller
The pump that drives water through the arms loses pressure as the impeller wears or a bearing goes. Arms turn slowly or barely at all. This is a genuine repair rather than a cleaning job, and it’s where the real diagnostic value sits — because it looks identical to #2 from outside the machine.
Overloading and Load Pattern
Not a fault, but a real cause. Bowls nested over the lower arm, oversized trays blocking the middle jets, and plates packed face-to-face all shadow the spray. If the dishwasher cleans well when half-loaded, this is the answer.
Before you call
Worth ruling out first. If one of these is the answer you’ve saved yourself a service call, and if none of them are, the diagnosis starts from a better place:
Bottom of the tub, usually a twist-lock cylinder. If it’s the first time, expect it to be unpleasant — and expect a noticeable improvement.
They should turn freely. Hold them to the light; clear any blocked jets with a toothpick or a straightened paperclip.
This pushes the cooled water out of the pipe so the dishwasher’s first fill is genuinely hot. If results improve, water temperature was your problem.
Many are set conservatively. Detergent performance falls off sharply below about 49°C at the machine.
If everything comes out clean, the machine is fine and the loading pattern is the fix — which saves you a service call entirely.
Why a real diagnosis matters
Several causes on the list above produce an identical symptom, and they sit at very different price points. That’s the whole argument for testing rather than guessing — a wrong part fitted confidently still leaves you with a broken appliance and a smaller bank balance.
Both produce dirty dishes and they’re completely different repairs. Measuring water temperature at the machine settles it quickly.
Slow-turning arms can mean a worn pump or simply blocked jets. Confirming which one avoids replacing a pump that was working.
In a hard-water city this is often the underlying story, and it responds to descaling rather than parts. Selling a pump to a scaled machine solves nothing.
If the load pattern or detergent dose is the cause, you deserve to hear that instead of a quote.
What the repair typically costs
Kodiak quotes labour as a flat rate per repair type, after diagnosis but before any work begins. Parts are quoted separately on your invoice. Typical labour ranges:
Wash pump, spray arm assemblies, heating element, diverter valve and inlet valve work falls in the $220–$350 range for labour. Parts quoted separately.
Sometimes the honest finding is that nothing is broken and the machine needs a thorough filter, arm and element service plus a change of habits. We’d rather tell you that than sell you a part.
Applied toward the repair if you proceed.
Your firm quote comes from your tech after diagnosis, before any work begins. You approve before we touch anything. Full pricing details.
Ready when you are
Kodiak Appliance Repair covers Calgary and area. Send us the details, or call with a question — we pick up.
More resources
Dishwasher Repair Calgary
All brands, all dishwasher symptoms.
Dishwasher Not Draining
Standing water in the bottom is a different problem.
Right Detergent, Right Job
Dose, type, and why more isn’t better.
Appliance Maintenance Guide
What to clean and how often, appliance by appliance.
Honest, flat-rate appliance repair in Calgary and area. Run by a working tech who wants to do it right.