Illinois Plumbing Code Practice

The correct temperature setting for a thermostatic mixing valve to prevent water from exceeding safe levels is 120 degrees Fahrenheit. This temperature prevents scalding while still providing a comfortable water temperature for typical household use. Setting the valve at this temperature ensures that water delivered to fixtures, such as showers and sinks, is hot enough for effective use without posing a risk of burns, especially for vulnerable populations like children and the elderly.

In the context of the Illinois Plumbing Code, maintaining safety guidelines around water temperatures is essential for reducing the risk of thermal injury. Lower settings, such as 90, 100, or 110 degrees, may not provide sufficient heat for effective sanitation and comfort, particularly in situations where a higher water temperature is required for specific tasks, such as washing dishes or laundry. Therefore, 120 degrees strikes a balance between safety and functionality.