Getting and keeping the proper hot water temperature requires you as a home owner to properly test your hot water. The only way to do this is with a thermometer which can be purchased at any hardware store. See picture.
As of today the CDC recommends that domestic hot water not exceed 120′ Fahrenheit at any faucet. Since it is difficult to keep your water heater at 120 Fahrenheit constantly I recommend you set your water heater from 110′-120′ Fahrenheit.
Test your house water temperature by starting at the furthest fixture. Let the hot water get hot and then proceed to test. See picture.
Record this temperature. Next you will want to go to the next bathroom or floor depending on your home. If you have three floors to your home you probably started on the third level taking your first water temperature sample. You would go to the second level and then down to the first level. Record all the temperatures to insure the temperatures are very close in degrees.
If after taking the temperature of all your faucets you find the water is too hot or too cold you will need to adjust the temperature to your water heater, boiler, etc. Adjusting the temperature on a water heater is simple. You will see a controller on the bottom of most water heaters that looks something like the picture you see here.
On this controller you would adjust the black knob to the left to increase the temperature and to the right to increase the temperature. Check your particular controller for direction of heat. Once you make your adjustment I recommend yo wait at least one hour and re-test the water to insure you set the temperature correctly between 110′-120′ Fahrenheit.
Safety warning: After properly adjusting your water heater throughout your house you could add mixing valves to all your showers to prevent a possibility of scolding in case the water heater over heats. This is a plumbing code requirement for commercial buildings such has hospitals, schools, etc.
Hot water temperatures for commercial buildings including hotels, hospitals, commercial kitchens and many others should be tested monthly or more frequently in some instances, to insure hot water temperatures are correct and safe to control diseases. Normal ranges of hot water for these type of buildings range from 110F -180F. Check with your local Health Department and with the Center For Disease Control & Prevention.
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