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Quick Answer
Most modern dishwashers run a sensing cycle that sets its own length based on how dirty the water is, so anything from one to four hours can be normal. A genuinely abnormal cycle usually traces to a turbidity sensor coated in film, mineral scale on the heating element, or low water pressure.
A dishwasher that used to finish in ninety minutes and now takes three hours looks broken. Usually it is not: machines built in the last decade set their own cycle length as they run.
Why "Longer" Is Usually Normal
Older dishwashers ran fixed timers, whether the load held six glasses or baked-on casserole dishes. Modern machines sample the wash water mid-cycle, judge how much soil is in it, and adjust on the fly — extending the wash, adding rinses, or holding to heat further. That is why the same "normal" cycle can finish in ninety minutes one day and take three hours the next.
How Long Should a Cycle Actually Take?
| Cycle | Typical Duration |
|---|---|
| Quick / Express | 30 – 60 min |
| Normal / Auto sensing | 1.5 – 3 hours |
| Heavy / Pots & Pans | 2 – 4 hours |
| Eco / Energy Saver | 3 – 4 hours |
Inside these ranges, the dishwasher is behaving as designed. Only a cycle well past four hours, one that never completes, or one that stops with water in the tub is genuinely wrong.
5 Real Causes of an Abnormally Long Cycle
1 A Dirty or Scaled Turbidity Sensor DIY
The turbidity sensor sits in the tub floor near the filter and shines light through the wash water to measure how cloudy it is. The control board uses that reading to decide how long to wash and how many rinses to run.
When food film coats the window, every reading looks dirty and the machine responds with another rinse, then another. This is the most common cause of a cycle that has quietly stretched out over months.
Fix: find the sensor in your owner's manual, then wipe the window with a soft cloth and white vinegar. Nothing abrasive — a scratched lens misreads permanently.
2 Mineral Scale on the Heating Element Maybe DIY
Much of the GTA has moderately hard water. Over a few years, minerals bake onto the heating element as a white crust that insulates it from the water. The dishwasher waits, re-checks the temperature, and waits again — adding an hour with no error code.
Fix: run an empty descaling cycle with citric acid or a dishwasher cleaner on the hottest setting, repeating monthly if buildup is heavy. If cycle times do not improve, a technician should assess the element.
3 Low Water Pressure or a Half-Closed Supply Valve DIY
Every fill and rinse phase waits for the tub to reach a set water level. If water arrives slowly, each phase stretches, and a cycle with five or six fills accumulates the delay quickly.
Fix: confirm the shut-off valve under the sink is fully open — these get nudged closed while people store things there. Then run the kitchen tap on hot: weak flow points to household pressure, not the dishwasher.
4 An Eco or Energy-Saver Cycle Is Selected Not a Fault
This catches people out constantly, especially when a new dishwasher arrives with eco as the default. Heating water is where a dishwasher spends most of its energy, so eco heats less and makes up for it with a long soak. Three to four hours is normal, and dishes come out just as clean.
Fix: nothing is broken. If you need the load sooner, select normal or heavy. Check the panel before assuming a fault — a household member changing the default explains many "sudden" complaints.
5 A Failing Heating Element or Control Board Professional
If the heating element has failed outright, the water never reaches target temperature and the machine sits in a retry loop — sometimes six hours, sometimes stalling with water in the tub. A control board fault does the same: it misreads the temperature sensor and repeats a completed phase.
Fix: both need a certified technician. The distinguishing symptom is a cycle with no end rather than one that is simply slow, often with dishes cool and wet.
Check These Before Booking a Technician:
Do not judge by the countdown display. The time shown at the start is an estimate from the last similar load, and sensing dishwashers revise it mid-cycle. A jump from 1:20 to 2:40 is honest reporting, not a fault.
What a Repair Costs
| Cause | DIY Possible? | Pro Repair Cost |
|---|---|---|
| Dirty turbidity sensor | Yes — free | Not needed |
| Scale on the heating element | Maybe | $150 – $280 |
| Heating element replacement | No | $180 – $320 |
| Control board failure | No | $200 – $350 |
Prices include parts and labour. We charge an $89 Diagnostic — Waived with Repair, with a 90-day warranty. See our dishwasher repair cost guide.
Limited-time offer: $40 OFF any repair. Book online or call (437) 747-6737.
When to Call a Technician
Book a visit when a cycle runs well past four hours, never completes, stops with water in the tub, or ends with dishes cool and wet — the machine cannot finish, rather than choosing to take longer.
We service Toronto, North York, Scarborough, Etobicoke, Mississauga, Brampton, Vaughan, Richmond Hill, Markham, Oakville and the surrounding GTA, Monday to Saturday 8am–8pm and Sunday 9am–6pm.
Frequently Asked Questions
Anywhere from about one hour to four, depending on the cycle and how dirty the load is. A quick wash runs roughly one hour, a normal sensing cycle two to three, and an eco cycle three to four. Modern machines set their own length, so two runs of the same cycle can differ by an hour.
Usually a turbidity sensor coated in film, which keeps reading the water as dirty and makes the machine add rinse phases. Mineral scale on the heating element is next most likely, because the water takes longer to reach temperature. Also check nobody changed the cycle setting, since eco modes run longer by design.
A small optical sensor, usually in the tub floor near the filter, that shines light through the wash water to measure how cloudy it is. The control board uses that reading to decide how long to wash and how many rinses to run. Food film on the window makes every reading look dirty.
Yes, and that is the point of it. Heating water is where a dishwasher uses most of its energy, so an eco cycle heats less and compensates with a much longer soak. Three to four hours is normal. If your cycle time jumped and nothing else changed, check whether eco is selected.
Yes. Much of the GTA has moderately hard water, which leaves mineral scale on the heating element. Scale insulates the element so water heats more slowly, and the machine waits and keeps checking until the target temperature is reached. Descaling every few months usually brings cycle time back down.
When the machine runs far past its longest normal cycle, never finishes, or stops partway with water still in the tub. A cycle stretching well beyond four hours or repeating phases indefinitely usually means a failing heating element or a control board stuck in a retry loop. Both need a technician.