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Want Lower Utility Bills? Lower Your Water Heater Temperature


As an efficiency-minded homeowner, you should be constantly on the lookout for ways to save money on utility bills. One way to improve energy savings that you might have overlooked is by reducing your water heater temperature.


Have a look at the thermostat of your water heater. Is it set on 140 degrees?

Water heater manufacturers often choose a factory setting of 140 degrees, but you need not leave it there. For most households, a temperature of 120 degrees is adequate. Lowering the temperature that much not only saves energy, but also reduces the chances for scalding. A slightly cooler temperature also reduces the mineral buildup and corrosion that occur over time in the water heater and its plumbing.


Turning down the thermostat helps you save in two ways.

Standby losses are continuous when you have a storage tank water heater, as the heating element works non-stop to keep the water from losing temperature in the tank. Those losses are increased when the water heater is in an unconditioned space, such as a basement or garage. Trying to maintain a continuously high temperature of 140 degrees obviously makes the heating element work even harder.

There's also a question of demand. Whether you're one person to a house, or in a house full of people, the more demand for hot water, the harder the heating element has to work. Once again, if you lower the thermostat, the water heater doesn't have to work as hard to keep replenishing that hot water.


Sometimes dishwashers without booster heaters require water temperatures of 130-140 degrees to optimize cleaning, so check your manual before lowering the water heater thermostat.

Also, if you have individuals in your home with compromised immune systems or chronic respiratory issues, you might need to keep the water at 140 degrees. There is a slight risk that legionellae can grow at a lower temperature.

Visit the Valley Heating, Cooling, Electrical website for in-depth information on most HVAC topics, or just give us a call at (408) 868-5500.

Our goal is to help educate our customers in the greater San Diego and San Marcos, California area about energy and home comfort issues (specific to HVAC systems).

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