Average Hot Water Heater Temp

Being hot or being cold? One of the questions for the ages but is there a better solution? How hot is enough and how can we be more effective when it comes down to setting the temperature in the water heaters. Simple searches (and reports by The Consumer Product Safety Commission) will let you know that having the temperature set on 120 F (or 49 C) is best for your home – but is it really that simple? One setting to rule them all – is our shower using the same temperature setting as the dishwasher for example? Here is more information about this topic and what should we stress on.

The 120 F Shower Rule

Different researches will show you that the regular temperature set in our homes should be 120 F or 130 F (especially for the United States). This is because of a small bacteria called Legionella. The bacteria is reportedly dying in 5 minutes or less if the temperature is above 122 F (growing if less than 108 F and just surviving if the temp is between 108 F – 122) F. Of course, we can try going over 140 F and the bacteria will die even quicker, but that is definitely not recommended as we would suffer as much as the bacteria itself. And this is not even mentioning the fact that by having a higher temperature set in our house, the electric (or gas) bill will rise as well.

Many studies show that showering with cold water is very beneficial to our body but yet – we still take long, hot showers. Let’s face it – who likes cold water? And wanting to have a normal (hotter) shower is part of being human. If the water heater is far from the shower, then we might need to set the temperature even higher.


The shower is not the only thing we need to think about when we are adjusting the water heater at home. Most modern dishwashers are generally set at 140 F by the manufacturers and they will be heating the interior as well. If you have an older model – please check the specifications. Most detergents are different, having different proportions and requirements, but there is a general rule with them as well – setting the temperature between 122 F and 140 F will deliver the most satisfying results from the dishwasher.

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