water heaters and tempurature settings

interesting article


It was interesting, especially since the manufacturer’s recommended setting is usually 120°F-125°F, and the article says that anything under 140°F will allow Legionnaire’s Disease to incubate. Hmmmmmmmmmmm. Seems like the water heater manufacturers would have picked up on that.

I believe all new tanks In Canada are set so the temp can not go below 150 degrees . they also must have a tempering valve with all new installations . Roy Cooke

Wont anything over 120 degrees burn small children on contact?

thus the requiremnet for the tempering valve

The mixing valve will not allow water to exceed 120 degrees.

I have found tempering valves that will not go above 108 degrees .
Many plumbers do not know if they take the handle off they can set the inside to raise the temp to 120 degrees.
Roy Cooke Royshomeinspection.com


I suspect they didn’t torture any small children to find out, but here’s some information for adult skin. Draw your own conclusions.

About Homes


Thanks For Info!! Resposible Parents Should All Know This Info.


Here is the time to burn info for a child’s skin.
Water Heater Safety.pdf (45.3 KB)

So someone did torture children. Probably juvenile delinquents. :slight_smile:

Probably when they were very youg so they would forget.:twisted::wink:

Or they were under the influence of Ms Margarita and Dr Cuervo. :margarit:

most new water heaters come set all the way down so the installer is forced to adjust the temp. thus relieving the manufacturer of the responsability of scalding. The temps set in NH are 120 at showers and 130 at sinks. Our town requires the mixing valve mainly because a 40 gal water heater does not get the proper first hour gallon rating required by the plumbing code. By installing the mixing valve you can over fire the water heater to 160 and temper it down to 130 by adding cold resulting in more gal. per hour of hot water. This also a way to install a smaller water heater when you have a large whirlpool and not size the heater to match a fixture that gets used so little. A plumbing inspector showed me a quick way to test temps that is really amazingly accurate, on a sink, if you can hold your hand under the hot water for roughly 3 or 4 seconds befor it starts to burn that should be about 130. If you can’t keep it for even a second, tooooo hot.

Our local plumbing inspector would fail you if it were set over 120 degrees. It’s a catch 22 situation- Legionnaires disease or law suits for burns.

Then would they take the responsibility for diseases from insufficiently hot water?