Reasons why 120 degrees is optimal
The US Department of Energy and the American Society of Sanitary Engineering concur that 120 degrees is the ideal temperature for a water heater. The advantages of this temperature include:- It’s better for the environment.
- Saves you money
- Prevents mineral buildup
- Prevents scalding
Reasons why 140° F is optimal
Given the risk of scalding, why would anyone risk using a higher temperature? According to the Occupational Safety and Health Administration 140° is considered a safe temperature. The website specifically states that bacteria are killed at this temperature. Bacteria that can spread Legionnaires' disease (pneumonia-like disease) are killed at 140° Fahrenheit. However, homeowners don’t have to be too concerned as most bacteria are eliminated at 120° F.![](https://cdn.shopify.com/s/files/1/0540/7899/6674/files/fresh-shower.jpg)