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Hot Water Temperature

Hot water temperature - How can I control the hot water temperature?

by David Sanner

A common way to moderate water temperature is to use a mixing valve. A mixing valve has a setting for maximum temperature (usually adjustable). They are also referred to as anti-scald mixing valves. On a typical three way mixing valve, one side has a supply hot and cold water connection, on the other side the mixed water continues on, supplying hot water to the system. If the hot water entering the mixing valve is below the mixing valve setting it simply passes through but if it is above the setting it is mixed with enough cold water to lower the temperature to the set temperature. They are pretty basic thermo-mechanical devices that can be found at most plumbing supply stores. Make sure that you size the valve correctly for your typical flow rate. It's nice to always have the same hot water temperature, regardless of the hot water tank's temperature, until you run out of hot water that is... Besides the benefit of not scalding oneself, you save time and *hot water* not adjusting the temperature each time you turn on the faucet.


Craig Illman, Espresso #1150, Seattle

I added a tempering valve to Espresso last year. I purchased one online from Pex Supply. I'd recommend getting the Low-Temp 100-130 degree version.