What is a tempering valve?

What is a tempering valve? www.americanplumbingla.com #americanplumbing #geriatricgymrat #temperingvalve #federalgovernment #plumbingrepairs

A tempering valve is a plumbing device that mixes hot water with cold water to deliver water at a safe, controlled temperature.

What it does

• Blends hot and cold water automatically

• Prevents water from getting too hot, reducing the risk of scalding

• Keeps outlet water temperature consistent, even if pressure or supply temperature changes

Where it’s commonly used

• Showers and bathtubs

• Sinks (especially in healthcare or childcare settings)

• Water heaters (to allow storage at high temperatures while delivering safer water)

• Commercial buildings and residential homes with safety codes

Why it’s important

• Water heaters often store water at 60°C / 140°F or higher to prevent bacteria growth

• Direct hot water at that temperature can cause burns in seconds

• A tempering valve allows safe delivery (often around 49°C / 120°F or lower)

Tempering valve vs. mixing valve

• Tempering valve: typically controls temperature for a whole system

• Thermostatic mixing valve (TMV): more precise, often used at individual fixtures

Simple example

Think of it like a thermostat for your water—it adjusts the mix so the water coming out isn’t dangerously hot.