Setting the right temperature on your water heater affects more than just comfort. It plays a key role in both safety and energy efficiency. If the water is too cool, harmful bacteria like Legionella can thrive. If it’s too hot, it can cause scalding injuries and drive up your utility bills. Striking the right balance helps ensure you have reliable hot water without added risk or waste.
Standard Water Heater Settings
Most water heaters are factory-set at 140 degrees Fahrenheit. While this temperature guarantees consistently hot water, it is not necessarily the best setting for your home.
The US Department of Energy recommends setting your water heater to 120 degrees for safety and efficiency. Although the 20-degree difference might not seem like much, it can lower your energy costs, reduce the risks of scalding injuries, and extend your water heater’s lifespan.
The Right Spot for Efficiency and Comfort
Setting your water heater to 120 degrees provides water that is hot enough for most household tasks, such as showers, laundry, and hand-washing dishes. It also reduces the risk of burns and uses less energy than higher settings. This setting can help lower standby energy losses and reduce your overall utility bills.
Protect Against Scalding Injuries
A 120-degree setting is safer for households with young children, older adults, or anyone with sensitive skin. At 130 degrees, a third-degree burn can happen in just 30 seconds. At 150 degrees, it takes only two seconds.
In addition to lowering your water heater’s temperature, you can install an anti-scald device. Also known as mixing or tempering valves, these devices blend cold and hot water to reduce the risk of burns. They provide extra protection, but the most important step is to lower the temperature at the source.
When You Might Need a Higher Temperature
In some situations, a higher water heater setting may be necessary. For example, if someone in your household has a compromised immune system, setting the temperature to 130 degrees can help prevent the growth of Legionella bacteria.
In these cases, many homeowners in Littleton choose to install a water heater booster. This device keeps the tank at a higher temperature but blends in cold water before it reaches your faucets, reducing the risk of scalding.
The Risks of Going Too Low
While higher temperatures may be necessary in some households, going too low can also introduce problems. Although it might seem like a good way to save energy, setting your water heater below 120 degrees can increase the risk of bacterial growth.
Several types of bacteria thrive in water temperatures between 77 and 113 degrees. If your water heater does not consistently maintain a temperature above this range, especially during periods of low water usage, bacteria can multiply in the tank. This is especially concerning in older systems or in homes where hot water sits unused for long periods, such as in vacation homes.
A 120-degree setting strikes a balance between energy efficiency and safety. It is hot enough to keep most harmful bacteria in check while reducing the risk of scalding and cutting down on energy costs. For most households with regular hot water use, this temperature provides safe, reliable hot water without the risks that come with either extreme.
Energy Savings and Monthly Impact
According to the US Department of Energy, water heating accounts for around 18% of a home’s energy usage. The department states that reducing your water heater temperature from 140 to 120 can help you save up to 10% on energy costs. Even if you don’t see an immediate impact on your monthly bills, the cumulative savings you experience can add up over time.
Adjusting the Temperature on Your Water Heater
Changing the temperature of your water heater is usually a straightforward process. The exact method depends on your type of water heater. Always follow the manufacturer’s instructions, but here are brief guidelines for standard models.
Gas Water Heaters
Most gas water heaters have a temperature control dial near the tank’s bottom, usually behind a removable panel or cover. This dial usually has settings between 90 and 160 degrees and labels such as “Warm,” “Hot,” and “Very Hot.”
Electric Water Heaters
First, shut off the electricity. Then, open the access panels on the side of the tank to reveal the thermostat. Most units have upper and lower thermostats, and both need adjusting.
Tankless Water Heaters
Tankless water heaters feature a digital display. You can adjust the temperature to 120 degrees or your preferred level from the settings menu.
Professional Services to Keep Your Water Heater Running Efficiently
Aside from changing your water heater temperature, a few simple habits can help you get the most efficiency from your unit.
Tank and Pipe Insulation
Pipe and tank insulation helps reduce heat loss, especially during the cold months. Insulation prevents freezing, reduces condensation, and can help improve overall efficiency.
Annual Tank Flushing
Over time, sediment buildup reduces heating efficiency and can shorten the tank’s lifespan. Annual flushes are essential parts of water heater maintenance. Flushing the tank removes the sediment buildup and helps your water heater work more efficiently.
Repair Problems Promptly
Plumbing problems like dripping faucets can waste water and the energy used to heat it. An annual plumbing inspection can help us find and repair minor issues immediately.
Install Low-Flow Fixtures
Low-flow fixtures help conserve hot water and reduce the overall demand on your water heater. We can help determine which fixtures work best in your kitchen and bathrooms.
Seasonal Adjustments and Special Considerations
During the winter, the water coming into your tank is much colder, making your water heater work harder. You may need to slightly increase the temperature to around 125 degrees to improve comfort without risking serious burns.
Larger households with multiple simultaneous hot water users may also benefit from a slightly higher temperature adjustment. Installing thermostatic mixing valves at each fixture can provide safety and allow you to meet hot water demands.
When to Call a Professional
While adjusting your water heater’s temperature is usually simple, certain issues may require professional help. If you’ve set your thermostat but still experience inconsistent water temperatures or difficulty maintaining your preferred setting, there may be a problem with the thermostat or heating element. Some older units lack clear temperature markings or have internal controls that are hard to access safely. In these cases, our plumbing professionals can inspect your system, confirm safe temperature settings, and ensure your water heater is operating efficiently and correctly.
Contact Your Local Water Heater Professionals
At Summit Heating, A/C, Plumbing & Electrical in Littleton, CO, we help homeowners keep their water heaters running safely and efficiently. We provide services for residential and commercial customers in Littleton and surrounding areas. Our plumbers install, maintain, and repair all water heaters, including gas, electric, and tankless. Contact us at Summit Heating, A/C, Plumbing & Electrical today to schedule an appointment with one of our experienced plumbers.
