Safe Water Heater Temperature – What Temperature Should You Set?

The appropriate temperature must ensure while doing a shower. Nothing is worse than getting scalded in the shower because of the high water temperature. Many diseases occur due to stagnant water, like legionnaires disease, one type of pneumonia. A water heater user should know the Safe Water Heater Temperature in their home if they set the right temperature according to a situation like doing showers, washing things, seasonal demand, and many more.

Safe Water Heater Temperature

Water heater – Issue of Goldilocks

In the segment, there are two primary and opposing risks:

  • If the temperature of the water heater is too high, a person may get scalded in many cases.
  • The low temperature of the water heater may develop the risk of pathogens, particularly a disease called Legionnaires.

Problems with minimum temperature

There is a research paper called Legionella and its way of prevention found on the website of the World Health Organization. In that paper, it showed the details of the temperature in water and the effect of the survival of Legionella.

Summary of the research paper

  1. Legionella bacteria dies instantly when the temperature is above 70 degree Celsius (158 degrees Fahrenheit).
  2. With 60 degree Celsius or 140 degrees Fahrenheit, 90% of the disease bacteria die within minutes.
  3. At 48 to 50 degree Celsius (118 to 122 degrees Fahrenheit), the bacteria disease survives but cannot multiply.
  4. The disease grows quite effectively when the temperature is around 32 to 42 degree Celsius (90 to 108 degrees Fahrenheit).

The dishwasher temperature is to be set at

There are many changes in the dishwasher models, including in the temperature section. Today’s model dishwasher has a minimum requirement of 49 degrees Celsius (120 degrees Fahrenheit). You will find heaters in most products. Heaters heat the interior according to need. A user checks specifications if they have an older model. Many dishwasher detergents vary in temperature requirement. But it works ideally between 50 and degree Celsius. Cold water detergent on the market works at any temperature required to wash.

When the temperature s set to a maximum limit?

Scalding happens when the temperature is set very high. When the tap s opened first, the water in the pipe gets slightly more relaxed, and the temperature will increase dramatically once the water from the tank reaches the point for use. Tiny babies, older people, and children are at risk because of their thin skin. Conversely, older people’s skin is less sensitive, and they feel the scald damage later. Older people will get many problems because of their slow movement when they find the water is boiling. The Consumer Product Safety Commission (CPSC) suggested setting the temperature at 49 degree Celsius or 120 degrees Fahrenheit. The commission is very experienced in research, and their recommendation is highly reliable.

Related Link: How to Condense Hot Water Consumption for Energy Savings?

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Related Link: How many gallons of water is used in a shower per minute?

Dead Legs

Dead legs contain stagnant water. It’s the ideal breeding ground for bacteria and contaminates the entire system. Water found in the dead leg gets warm but never gets too hot. It does not mix with the temperature of the main flow.

The valve needs to e installed in the closed section of the main line. The valve would be no more than one pipe diameter away. Thus, it minimizes the risk of developing stagnant water and bacteria.

Pipe issue in PEX vs. Copper

In a research study, it has found that Legionella grows faster in PEX than copper. The development occurs for throughout 500 days. Again, within 800 days, the growth is stable. Both pipes have similar biofilm formation.

Copper cools down faster than PEX. If there is enough given time, the temperature of both will cool to low. In some cases, insulation does not work. Even with insulation, water in pipes gets excellent at its ambient level.

Some conflicting views

In a debate, some experts of the Canadian Commission on Building and Fire Codes (CCBFC) rejected the lower maximum of the hot water tank temperature, which is 49 C. By keeping the statement in mind, many trusted organizations are advising homeowners to be quiet the temperature at 49 C as a precaution against scald comes from the tap. Many people offer tips to find the thermostat so the user can adjust the issue by them.

Bottom-line view

Water should be stored at a high temperature to prevent getting bacteria into it. Then, it is to be delivered from the tap at a low temperature to avoid scald problems.


Our team of experts researched many papers and articles. The best way is to install anti-scald mixing valves at each human point, like the sinks, tubes, taps, and those places where water comes out for use. Whether it is integrated into the shower valve or installed under the sink. The tank is to be set to 60 degrees Celsius, according to the World Health Organization (WHO) report. Many scientists and biologists have found the temperature in this view of WHO is a proven fact. In each human point of use, the limit is 49 degree Celsius or 120 degrees Fahrenheit. The temperature can be low in a kid’s bathroom, like 110 degrees Fahrenheit. For other use like dishwashers, washing machines, and humidifiers, the temperature is a bet placed to full 60 degree Celsius. So safe water heater Temperature is the most critical factor in preventing the risk of unexpected accidents.

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