You Can Adjust Your Water Heater’s Temp and Save

That water heater sitting in your garage or basement silently accounts for about 18% of your home’s energy use. The good news is you can knock that energy use back a bit with one simple adjustment. Then you can go back to letting it provide you with warm showers and clean dishes.

By adjusting your water heater down by a few degrees, you can enjoy the same water heating performance for less water heating cost. Here’s how to do it and what else you need to know.

What temperature should you set your water heater to?

For most water heaters, 120 degrees Fahrenheit is the recommended temperature for safety, energy efficiency, and health. While many water heaters are factory-set to 140 degrees, lowering the temperature can have significant benefits.

• Energy savings: Reducing the temperature by 10 degrees can save 3-5% on your energy bill.
• Safety: A setting of 120 degrees greatly reduces the risk of burns. Water at 140 degrees can cause a third-degree burn in as little as five seconds, a risk especially dangerous for children and the elderly.
• Longer lifespan: A lower temperature setting slows the buildup of mineral deposits or scale in the tank and pipes, which helps maintain efficiency and extends the lifespan of your plumbing and water heater.

If you are looking for more significant improvements, you might also consider upgrading to a heat pump water heater or a tankless water heater.

There are valid reasons to leave your water heater’s temperature at 140 degrees. One, if you have a high demand for hot water, which could be due to a larger household or certain appliances. An older dishwasher, for example, may not have its own heating element and require hotter water for effective cleaning.

Additionally, a higher temperature is a critical safety measure in specific health-related situations according to the Centers for Disease Control and Prevention. For households with immunocompromised individuals or those with a chronic respiratory disease, a 140-degree setting is necessary to kill bacteria like Legionella that can grow in warm water.

How much can you save by adjusting your water heater?

Reducing your water heater's temperature from 140 to 120 degrees can cut your water heating energy costs by 6-10%. The exact amount you save will depend on factors like local utility rates, tank size, and water usage.

This adjustment also saves you money on reduced standby heat loss — the heat that escapes from water on standby in the tank. The Department of Energy estimates this can save an average household $36-$61 per year.

The Department of Energy estimates this change can reduce your annual water heating energy consumption by 4-22% and spending less on hot water across all home uses and appliances can save more than $400 a year. While savings depend on your local electric and gas rates, electric water heaters generally see a slightly greater reduction in cost.

(Another way to tackle standby heat loss is with insulation. Insulating the first few feet of the pipe leaving the water heater can help. So can adding a water heater blanket to a standby tank that feels warm to the touch, if it’s safe to do so.)

How to change the temperature on your water heater

Changing the temperature on your home water heater is a fairly easy task, but turning power off to the heater before working on it is a critically important safety step. When in doubt, ask the technician when they're next at your house to service your water heater.

For electric water heaters: 

• Turn off the power: Turn off the electricity to the water heater at your electrical panel to prevent electric shock.
• Remove access panels: On the tank, there are normally two panels. Remove them with a screwdriver. 
• Pull back insulation: After opening the panels, there could be insulation you need to move to get to the thermostat and dials.
• Adjust the thermostats: You might need a flathead screwdriver. Set both thermostats to the same temperature.
• Replace insulation and panels: Replace everything and secure the panels.
• Turn the power on: Turn the power on at the circuit breaker.

For gas water heaters:

• Find the temperature dial: It is usually on the bottom of the tank, on the gas control valve.
• Adjust the dial: Turn it to 120 degrees, or sometimes it’s a “warm” or “vacation” setting.
• Wait then check: Wait a few hours, then you can check the water temperature at a faucet with a thermometer.

If you’re interested in more ways to save energy (and money) at home, download the new Palmetto app or explore Palmetto’s Savings Maximizer. You can also learn more about home solar panels and get a solar estimate for your home with our solar savings tool.

Frequently asked questions

What temperature should a water heater be set at?

Water heaters are typically factory set at 140 degrees Fahrenheit. For most homes, a water heater can be set at 120 degrees for energy savings and a safe water temperature. 

How do you adjust the temperature on an electric water heater?

Adjusting your water heater temp involves a few steps. First, turn off the electricity to the water heater before doing any work with it. Then, remove any access panels, find the thermostats and adjust them. Then, replace the panels and turn the power on.

Can I set my water heater below 120 degrees?

You can, but it’s not recommended. Water cooler than 120 degrees is susceptible to bacterial growth and can cause illnesses.

Are there other simple energy changes that can save me money?

Yes, depending on your home. Conduct a quick DIY energy audit to see what efficiency gaps your home has. Swapping in LED lightbulbs, sealing gaps around doors and windows are quick fixes. Buying or leasing solar panels are bigger moves that can pay off in the long run.