The sanitize option makes the dishwasher heat its final rinse hotter than a normal cycle and hold that temperature long enough to kill most bacteria. It adds time and energy, so it is worth knowing what it actually does and when it makes sense.
How it works, step by step
- You add the option to a wash cycle. On most models, sanitize is a button you press with a cycle like Normal or Heavy.
- The wash runs as usual. Soil removal is handled by the same washes and rinses as the cycle you chose.
- The final rinse gets extra heat. The heater raises the last rinse to a higher target. Under the NSF/ANSI 184 standard for residential dishwashers, a certified sanitizing cycle must reach a final rinse temperature of 150°F.
- The cycle holds at temperature. The dishwasher waits while the heater works, which Whirlpool's water temperature guide describes as extra time needed to heat water to the proper temperature for cleaning or sanitizing.
- The result is checked. NSF says certified models must achieve at least a 99.999 percent (5-log) reduction of bacteria, and that only the sanitizing cycle is evaluated. Many models then light a "sanitized" indicator if the target temperature was reached.
What you'll notice because of it
- A longer cycle, because the final rinse has to heat further and hold.
- Hotter dishes and more steam when you open the door.
- A "sanitized" light at the end on many models, which only comes on if the rinse got hot enough.
- Higher energy use than the same cycle without the option.
- Better drying, since hotter dishes shed water faster.
Where it can go wrong
The sanitized light never comes on
Symptom: the option runs but the indicator stays off. Cold incoming water, a weak heater or a faulty temperature sensor can keep the rinse from reaching its target.
Cycles that run far longer than usual
Symptom: sanitize loads take much longer than they used to. The heater is taking longer to reach temperature, which often points to a heater or supply problem.
Warped plastics
Symptom: containers bent out of shape after a sanitize load. The higher heat is hard on plastics placed on the bottom rack near the heater.
A false sense of security
Symptom: no visible problem, but food residue left on dishes. Sanitizing is about the rinse temperature; it doesn't clean dishes the wash missed.
Getting the most out of it
- Use it when it matters, such as for cutting boards or after someone in the house has been sick, rather than on every load.
- Run the kitchen hot water until it is hot before starting, so the heater has less work to do.
- Keep plastics on the top rack.
- Look for NSF/ANSI 184 certification if a verified sanitizing claim matters to you. NSF keeps a searchable list of certified products.
- Keep the filter clean so the wash does its part before the rinse.
Because the sanitize rinse uses the same heater and temperature sensor as every other cycle, a light that never comes on is often the first sign of a heating problem. How a dishwasher heats its water walks through that system, and a dishwasher service visit can test it.
Sources
Worth knowing: A sanitized light that never turns on usually means the rinse isn't getting hot enough.
If your dishwasher's sanitize light stays off, call ProFix Miami at (786) 723-6874 to have the heating system tested.