Even though most units will go up to 160 degrees, you really shouldn't ever set the temperature higher than 140 degrees in order to reduce the risk of scalding. The EPA recommendation is to always leave your water heater set to 120 degrees.
That said putting the heater at maximum has two detrimental effects. It can heat the water too high increasing the risk of scalding and two, it can cause build up of pressure that will cause the pressure release valve to open and vent after which you may need a new valve.
Set the temperature too low, and you could turn your water heater into a breeding ground for dangerous bacteria. Set it too high, and you could be setting yourself up for a scalding accident. How Low Can You Go? The short answer: 120 degrees Fahrenheit.
Most homeowners mistakenly believe that their water heater's temperature is something they can't do anything about. In reality, your water heater has a thermostat that can be adjusted up or down, all in about five minutes.
If you put your water heater at maximum temperature set, or if the pressure relief valve of the water heater not functioning well then too much pressure can build in the tank, it may eventually spring a leak or might burst.
If you have younger children in the house, you are always better to have your water heater set to 120 degrees to prevent scalding. If there are no kids in the home or your children are older, we would usually recommend turning the unit up to 130 or 140 degrees.
120 degrees Fahrenheit is the safety recommendation against scalding, but 140° is the common default setting.
If the thermostat on the tank is set to a higher temperature, hot water may run out more quickly. Lowering it just a few degrees won't feel much different (it may even avoid being scalding burns). It'll also avoid a sudden rush of chilly water. Hot water can also run out if the heater is set too cool.
If you notice signs of overheating like scalding water, a leaking pressure relief valve, unusual sounds, rusty water, and climbing energy bills, you need to take swift action to repair your water heater before it causes more problems.
Manufacturers often recommend a hot water heater temperature between 120 to 140°F, and there's a reason for this. The Occupational Safety and Health Administration (OSHA) recommends a recommended hot water temperature of at least 122 degrees to prevent the growth of harmful bacteria.
As the water temperature increases, the faster pathogens are killed. That's one reason why some health experts recommend 140 degrees Fahrenheit for households with family members who may be immunocompromised. It is important to point out, however, that 140 degrees is very hot.
Savings resulting from turning down your water heater temperature are based on reducing standby losses (heat lost from water heater into surrounding area). Set too high, or at 140ºF, your water heater can waste anywhere from $36 to $61 annually in standby heat losses.
Faulty fixtures or leaking connections and pipes can go unnoticed at the water heater because it is not an appliance you see every day. The leaks can become significant and result in an increase in the water usage bill and your energy usage bill.
If the temperature is too low, your water heater can become a breeding ground for dangerous bacteria. On the other hand, setting the temperature too high puts your family members at risk of scalding themselves, leading to potentially serious injuries.
Elevating a Water Heater Addresses Safety Concerns
Elevating the water heater helps protect it from water damage and minimizes the risk of electrical malfunctions or gas leaks that could result from flooding.
The best temperature setting for a hot water heater is between 120 and 140 degrees. Below 120 degrees, bacteria can develop in the stagnant water sitting in the tank. Above 140 degrees, the water is so hot that you and your family members can be at risk for scalding in as little as two seconds.
THE DANGERS OF SETTING WATER HEATER TEMPERATURE TOO HIGH
When the temperature is above 140 degrees Fahrenheit, it takes only a few seconds to cause a serious burn. A higher temperature setting can also increase the risk of pressure buildup in the tank, leading to potential explosions or leaks.
While today's water heaters are better designed than older models, they still require regular maintenance in order to prolong their lives. With regular inspection, draining, and flushing, you can expect a gas water heater to last anywhere from 8-12 years and an electric water heater to last anywhere from 10-15 years.
At 150 degrees Fahrenheit (66 degrees Celsius), it only takes two seconds to suffer third-degree burns. The Consumer Product Safety Commission (CPSC) recommends setting the water heater at no more than 120 degrees Fahrenheit (49 degrees Celsius) to prevent scalding.
Most manufacturers set the temperature at 120 degrees Fahrenheit, which is the temperature we also recommend. Anything above 120 degrees Fahrenheit, puts you at risk of scalding. This is especially dangerous to children, the elderly, and anyone with sensitive skin.
Yes, it's very bad to turn your water heater all the way up. To do so will reduce its life, increase your electricity bill and could possibly cause scalding—particularly if you have young children or an elderly relative living in your home.
C - 150° F - About 1-1/2 seconds. B - 140° F - Less than 5 seconds. A - 130° F - About 30 seconds. HOT - 120° F - More than 5 minutes. LOW - 80° F - No hazard.
Most homeowners should flush their water heaters every 6 months or so, but if you have extremely hard water, you may want to do it more often. Flushing your hot water heater could be necessary as often as every few months depending on the mineral content of your local water supply.
According to most dermatologists, the ideal shower temperature is anywhere between 98°F (37°C) and 104°F (40°C)—and no more than 105 °F (41°C). Rinsing under lukewarm water allows you to stay comfortable and maintain your body temperature while reaping all the benefits of both hot and cold showers.