Many people are unsure of the correct temperature to set their hot water tank at and do not realize that the temperature of your hot water is an important factor in household safety.

There are a few things to keep in mind when thinking about hot water temperature in the home, particularly if your home’s occupants include young children, the elderly, or those with suppressed immune systems. It is important to take the appropriate safety precautions to ensure that your hot water system prevents disease and injury, so you can rest easy knowing that your home is safe for you and your family.


Water Temperature and Safety Risks

Household hot water needs to be stored at a high enough temperature to kill potentially disease-causing bacteria, particularly Legionella, which causes Legionnaires’ Disease. Legionnaires’ Disease is a respiratory infection that leads to pneumonia and can be harmful and even fatal in some instances.

60 degrees C is often the default factory setting on hot water tanks. 60 degrees C (140 degrees F) is hot enough to ensure that dangerous bacteria like Legionella cannot survive. However, this temperature can scald you and cause serious damage to the skin, particularly for young children and the elderly.

Some people recommend setting your tank to 49 degrees C (120 degrees F) to prevent scalding. 49 degrees C is hot enough to kill most harmful bacteria, but it does not guarantee getting rid of all of it.


How to Keep Your Hot Water Safe

Both injury from scalding and disease from bacteria are legitimate safety concerns, so it can be difficult to determine the best course of action when it comes to your hot water tank temperature. You can protect yourself from both harmful bacteria and scalding hot water with a system that stores water in the tank at a high enough temperature to eradicate bacteria while giving you cooler water at the tap to prevent scalding. There are a couple of different ways that you can do this.

One option is to install a hot water tank booster. This is a device that keeps the water in the tank at 60 degrees C, then mixes it with cold water as it leaves the hot water tank so that the water coming out of your taps will be about 49 degrees C—hot enough for all your household needs but not enough to scald.

The other option is to have anti-scald devices installed right at each tap. Anti-scald devices monitor the temperature of the water and ensure that water comes out of the tap at a comfortable 49 degrees C. Anti-scald devices also account for changes in water pressure, so even if you are showering while someone else in the household is using cold water elsewhere, the anti-scald device will change the hot water pressure accordingly so that you don’t have a sudden burst of very hot water pouring onto you unexpectedly. Some faucets and showerheads have anti-scald devices built right in.