Direct answer
For the Whirlpool WDT730HAMZ dishwasher, plastic retention, rinse aid, selected option, final-rinse heat and vent/fan design affect drying. First, compare glass, ceramic and plastic in one load with the supported dry option.
What this covers
- Whirlpool WDT730HAMZ dishwasher (WDT730HAMZ)
- Whirlpool dishwasher; exact model determines filter, third rack, fan/heat and code display.
- The specific fault this record addresses: does not dry dishes
What it does not cover
- ×The same symptom on a different Whirlpool product line, which has its own record and its own cited source
- ×An on-screen error code whose meaning has not been checked against this exact model's manual
- ×Live electrical, gas, sealed-system, internal battery-cell or structural repair — a technician boundary, not a self-service step
Differential
What actually causes this, and how to tell them apart
These are ordered by how often each one is the answer, not by how easy it is to try. The point of the middle column is that two causes producing the same headline symptom rarely produce the same detail — that detail is what tells you which one you have before you change anything.
- 1
Rinse aid is empty or disabled
What separates it Water beads on glassware instead of sheeting off, and the rinse-aid indicator shows empty or the dispenser setting has been turned to zero.
How to confirm Refill it and set the dosage to the middle of the range. Many machines allow rinse aid to be switched off entirely, and it is often turned off by accident or left empty for months.
- 2
The final rinse is not getting hot enough
What separates it Everything comes out damp, including glass and ceramic, and the incoming water supply is not reaching the temperature the machine expects.
How to confirm Run the kitchen hot tap until it runs hot before starting the cycle, so the machine draws hot water from the first fill rather than heating a tub of cold. Selecting a Sanitize or Extra Dry option raises the final-rinse temperature further where the model offers it.
- 3
The load is packed so items nest and hold water
What separates it Pooled water in upturned cup bases, bowls and container lids, with items touching or overlapping.
How to confirm Angle concave items so they cannot hold a pool, and leave space between pieces so air and heat reach them.
- 4
The door was opened too early, or kept shut too long
What separates it Dishes are dry at the end of the cycle but damp later, or steam is released when the door is opened straight after the cycle.
How to confirm Cracking the door open at the end of the cycle lets the humid air escape rather than recondensing onto the dishes. Unloading the lower rack first also stops water trapped on upper-rack items from dripping onto dry ones below.
- 5
A heated-dry or extra-dry option is available but not selected
What separates it Drying is poor on the default cycle, and the control panel offers a drying-related option that has never been turned on.
How to confirm Check which drying options the model actually offers rather than assuming — the naming and the underlying method vary between brands and between models in the same range.
Before you touch a setting
Record this first — changing settings destroys the evidence
Every item below stops existing the moment a reset, re-pair or settings change is made. Written down first, they are what separates the causes above; recovered afterwards, they are guesswork.
- Whether the split is by material — plastics wet, glass and ceramic dry — or whether everything comes out damp. These are two different problems.
- The rinse-aid level and dispenser setting, including whether it has been switched off entirely.
- Whether the kitchen hot tap was run before starting the cycle.
- Whether the door is opened at the end of the cycle or left shut until unloading.
Fill the rinse aid and confirm the dispenser is not switched off
ReversibleRinse aid lowers surface tension so water sheets off instead of beading, and it is frequently found empty or disabled.
Run the kitchen hot tap until it runs hot, then start the cycle
ReversibleThis lets the machine draw genuinely hot water on the first fill rather than starting from a tub of cold.
Select Sanitize or Extra Dry where the model offers it
ReversibleBoth raise the final-rinse temperature, which is what leaves the dishes hot enough to dry themselves.
Reload so concave items are angled and nothing nests
ReversibleCup bases, bowls and container lids left flat will hold a pool of water no drying method can remove.
Crack the door open at the end of the cycle and unload the lower rack first
ReversibleReleasing the humid air stops it recondensing, and unloading low-to-high stops upper-rack drips landing on dry items.
Model-specific
What is true of this model and not of its siblings
Generic advice for the product line fails here. Each item below is a property of this specific model family that changes which of the steps above apply to you.
- Model scope
- WDT730HAMZ. Whirlpool dishwasher; exact model determines filter, third rack, fan/heat and code display.
- Drying — heated dry (has an element)
- Heated-dry option with an element — dries plastics better than Bosch, but keep plastics off the tub floor to avoid melting. Rinse aid helps.
- Wash & racks
- Stainless tub with adjustable racks and a sensor cycle; check your build for a 3rd rack. Manual filter must be cleaned periodically.
- Drain path
- 'Won't drain' is usually the filter, drain hose, air gap, or an un-removed disposer knockout plug.
- Symptom boundary
- This record covers Whirlpool WDT730HAMZ dishwasher when it does not dry dishes. A different symptom on the same hardware, or this symptom on a different Whirlpool product line, has its own record with its own causes and its own cited source.
Stop boundary
When this stops being a self-service repair
Continuing past any one of these costs more than the repair saves — in safety, in warranty, or in evidence a technician needs.
- !Stop for melted items, a burning smell, smoke, or visible damage to any heating component — those are not drying-performance problems.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Where the manufacturer's article stops. Whirlpool Product Help publishes this as "Product Help". Official Whirlpool use, installation, maintenance, error-code and troubleshooting library. What that article does not carry is the model boundary — it is written for a product line, and WDT730HAMZ is the scope applied here. Where a control label, terminal, indicator pattern or reset sequence differs on your unit, the manual for that exact model is the authority, not this page and not the article.
Exact questions
Common follow-ups
My Whirlpool WDT730HAMZ dishes are wet at the end.+
If you are not using the heated-dry option, dishes rely on rinse aid and residual heat, so plastics stay damp. Turn on Heat Dry (or Sani Rinse) for hotter, drier results, keep the rinse-aid tank filled, and crack the door open after the cycle. Unload the bottom rack first so drips from above do not fall on it. This model does have a heating element, so it can dry better than a Bosch if you enable it.
Does rinse aid actually make a difference?+
Yes, and more than most people expect. It lowers the water's surface tension so it sheets off surfaces instead of forming droplets that have to be evaporated. If it has been empty or switched off, refilling it and setting the dosage to the middle of the range is usually the single biggest improvement available.
Should I open the door when the cycle finishes?+
Cracking it open helps. It lets the humid air escape rather than recondensing onto the dishes as everything cools. Unloading the lower rack first also matters, so water still sitting on upper-rack items does not drip onto pieces you have already dried.
Does this answer apply to every Whirlpool model?+
No. It is scoped to WDT730HAMZ. Whirlpool dishwasher; exact model determines filter, third rack, fan/heat and code display.
What should I record before troubleshooting not drying or wet dishes?+
Record the complete model identifier, exact message or indicator, software/firmware where visible, the operating stage and what still works.
Why is a factory reset not the first step?+
A reset can erase accounts, networks, maps, schedules or preferences without distinguishing not drying, wet dishes. The ordered checks preserve that evidence.
When should I stop and use qualified service?+
Stop for melted items, smoke, burning smell or a damaged heater.
Answer for the exact device and software version shown above.