Dishwasher High Temperature Wash: What It Does and Limits

What the high temperature wash option does

The high temperature wash option is a supplemental setting that raises the main wash temperature beyond the default low or medium setting. Many dishwashers let you activate it independently of the chosen cycle, so you can pair it with a normal or heavy cycle when you want extra heat.

The extra heat helps dissolve fats, oils, and baked-on residue that cool water cannot lift. It also shortens the drying time because the dishes are warmer when the rinse ends. For a full-size unit with this feature, compare models in our 24-inch dishwasher guide.

On most machines, the option works by energizing the heating element during the main wash phase. Some models also extend the wash time to allow the water to stay hot longer. This is why a high temperature wash often adds 10 to 20 minutes to the cycle, depending on the chosen program.

The sanitizing effect

Water temperature plays a role in reducing microorganisms on dishes. ENERGY STAR notes that certified dishwashers can boost water temperatures to 140 degrees Fahrenheit, which allows for improved disinfection compared to hand washing. That is the same range the high temperature wash option typically targets.

Still, a high temperature wash is not the same as a dedicated sanitize cycle. A sanitize cycle is designed to meet a stricter standard for pathogen reduction, often validated by certification. For everyday cleaning, the high temperature option reduces bacteria, but for immune-compromised households, use the sanitize cycle or follow local health guidance. See our sanitize cycle explainer.

The high temperature wash also helps with the removal of food residues that can harbor bacteria. By keeping the water hot enough, it minimizes the chance of bacterial regrowth during the cycle. However, you still need to scrape off large food pieces; otherwise, the heat will bake them on instead of loosening them.

Which loads benefit from high temperature wash

Heavily soiled loads such as lasagna pans, roasting dishes, and greasy frying pans respond well to the extra heat. The higher temperature softens caked-on food and helps the detergent work more effectively.

Loads that have sat overnight or for many hours also benefit because the water stays hot enough to prevent food from hardening further. If you are washing baby bottles, cutting boards, or items that touched raw meat, the high temperature wash adds a degree of reassurance, though it is not a replacement for thorough sanitization. Compact units with this option are listed in our countertop dishwasher guide.

Another good candidate is a load with a mix of plastic and metal items. The heat helps remove grease from plastic lunch containers and metal utensils without warping, as long as the plastic is marked dishwasher-safe and placed on the top rack. For very delicate items like fine china or crystal, skip this option because the high temperature can stress materials.

Limits and trade-offs

The main limit of the high temperature wash is energy use. Heating water takes time and power. Models with this option still must meet ENERGY STAR efficiency criteria, but using it on every load will increase your annual operating cost compared to a standard cycle.

Cycle time also stretches. The built-in heater runs longer to reach and hold the temperature. For lightly soiled dishes, this is unnecessary and can waste energy. You can skip it and rely on a shorter normal or light cycle.

Water use remains close to the base cycle because the option only changes the heating, not the spray volume. However, the extended runtime can cause the pump to work longer, which adds to overall consumption. As the EPA points out, less than 1 percent of Earth's water is available for human use, so keeping water use efficient is worthwhile.

Another trade-off is the potential for spotting on glassware. Very hard water plus high heat can leave mineral deposits that are harder to remove. If you have hard water, you might need to use a rinse aid or a water softener setting to prevent film. See our rinse aid article for details.

When to skip the high temperature wash

If your plates are only lightly used, like cereal bowls, coffee cups, and standard dinnerware, a normal wash at default temperature is sufficient. Running the high temperature option adds no benefit for these loads.

Also skip it when you are in a hurry. Quick cycles are designed for speed, and adding the high temperature option defeats their purpose, often pushing the total time well beyond an hour.

For energy-conscious users, reserving the high temperature wash for two or three loads per week can keep your energy usage lower. The ENERGY STAR program emphasizes that certified dishwashers save energy, but that savings only materialize when you choose the right cycle for each load. If you have a soil sensor, you might not need to manually activate the option, as the dishwasher will automatically boost temperature when it detects heavy soil.

High temperature wash vs. sanitize cycle

A high temperature wash is an intensity booster; a sanitize cycle is a separate program with its own set of actions. The sanitize cycle usually maintains a higher water temperature for a longer period and may include additional rinses to satisfy certification standards.

If you want the highest level of hygiene, choose a model with a sanitize cycle. The high temperature option can help, but it is not designed to meet a defined sanitization standard. For a quiet model that offers both options, see our quiet dishwasher guide.

Another difference is user control. With high temperature wash, you decide when to use it. With a sanitize cycle, the dishwasher follows a fixed algorithm to ensure the water stays hot enough for the required dwell time. If you frequently wash items that need extra hygiene, such as pet bowls or nursing supplies, the sanitize cycle is worth having.

Common misconceptions

One misconception is that high temperature wash will dry dishes better. While the extra heat can help the dishes retain heat for drying, the primary purpose is cleaning, not drying. The drying phase still relies on a heating element or fan, not the wash temperature.

Another is that high temperature wash damages all plastics. In fact, many plastic items are dishwasher-safe and can handle high temperatures. The risk is for thin or single-use plastics that are not rated for heat. Always check the symbol on the bottom of the container.

Some assume that high temperature wash automatically makes dishes safe for anyone. That is overstating its effect. It reduces bacteria but does not kill all pathogens. For clinical sanitization, look for a cycle that meets NSF or similar standards. Our sanitize cycle article explains the differences.

Using the high temperature wash effectively

Scrape off large food pieces before loading. The extra heat does not replace the need for good loading and detergent, but it does help with stubborn residue.

Position greasy cookware on the bottom rack where the spray arms are most powerful. The high temperature wash works best when the water can reach the soiled surface directly.

If your dishwasher has a soil sensor, it might automatically increase the temperature when it detects heavy soil. You can still manually activate the high temperature wash for consistent results. Drawer-style models are another option if you prefer a dedicated lower rack; see our drawer dishwasher guide.

For best results, use the option with a heavy or normal cycle rather than a quick cycle. The longer wash phase gives the heat time to work. Also, make sure your water heater is set at least 120°F; otherwise, the dishwasher has to heat the water more, which increases cycle time and energy use.

What to pick for your use

Questions

Is high temperature wash the same as sanitize?

No. High temperature wash raises water temperature to around 140°F to improve cleaning and disinfection, but it does not meet a specific sanitization standard. A dedicated sanitize cycle is designed to kill more microorganisms. See our sanitize cycle article.

Does high temperature wash use more water?

Generally, it uses about the same amount of water as the base cycle because the extra heat comes from the heating element, not additional water. The longer cycle may cause a slight increase in overall water usage due to extended pumping.

Will high temperature wash damage plastic items?

Plastics that are not marked dishwasher-safe can warp or melt at high temperatures. Check the item's label or place plastics on the top rack, away from the heating element. Use the high temperature option only for dishwasher-safe materials.

Can I use high temperature wash for every load?

You can, but it increases energy consumption and cycle time. For lightly soiled dishes, a normal or light cycle is more efficient. Reserve high temperature for heavy loads or when you want extra hygiene. Also, using it on every load may cause excessive wear on the heating element over time.

How do I know if my dishwasher has this option?

Look for a button labeled 'High Temp' or 'Sani' on the control panel. Some models include it as part of a heavy cycle, while others allow you to add it to any cycle. Check the user manual or the model's spec sheet. Our buying guides list which models include this feature.