The correct dishwasher temperature, according to GE, is between 120 and 150 degrees Fahrenheit. This high temperature allows the dishwasher to effectively clean and sanitize dishes. The water is heated by your home's water heater before entering the dishwasher, but many modern dishwasher models have a heating element that increases the water's temperature even further. This heating element also allows the dishes to dry in a hot environment for additional sanitation.
The water inside dishwashers is typically between 120 and 150 degrees Fahrenheit.
Why Do Dishwashers Get so Hot?
Dishwashers operate at high temperatures to increase the efficiency of cleaning and to help kill germs. Hot water is simply more effective than cold water at lifting debris from dishes and activating dish soap.
For a dishwasher to kill bacteria, its temperature must reach at least 140 degrees Fahrenheit, according to the World Health Organization. Since most water heaters aren't set this high, the heating element in the dishwasher helps kick the water temperature up to this germ-busting level.
It's important to note that not all bacteria will be killed by this temperature. Some require water to reach its boiling point (212 degrees Fahrenheit), which can't be reached inside a dishwasher machine. Don't rely solely on the heat from your dishwasher to sanitize dishes if you have a concern about food allergens, viruses or other health threats.
Adjusting the Dishwasher Temperature
The only way to adjust the temperature of your dishwasher is to adjust the temperature of your water heater. However, this will alter the temperature of hot water throughout your entire home, so make sure everyone in the household gets plenty of warning if you're cranking up the temperature in order to avoid scalding while showering or handwashing. An ideal temperature for your water heater is between 115 and 120 degrees Fahrenheit.
Is Your Dishwasher Running Cold?
If you suspect your dishwasher isn't getting hot water at all, make sure it's hooked up to the correct water line. It may have accidentally been installed on the cold water line instead of the hot water line. Unlike washing machines, dishwashers only connect to one water line since they don't offer a "cold wash" cycle.
After you're sure it's connected to the hot water line, verify the water heater is set to an appropriate temperature and that it's producing hot water by opening the hot water tap on the kitchen sink, allowing it to run and measuring the temperature of the water with a food thermometer. If the water heater isn't working, it may be time for a new one (water heaters have a lifespan of only 10 years, according to the International Association of Certified Home Inspectors).
It's also possible that the dishwasher isn't performing efficiently because the heating element is broken. Call an appliance service professional for assistance or, depending on the age and overall condition of the dishwasher, consider upgrading to a newer model.