How to make a water heater less hot?

You can make a water heater less hot by adjusting its thermostat setting. Most water heaters have a dial or digital display that allows you to lower the temperature. It’s important to do this safely, as excessively hot water can cause scalding injuries.

Why Lower Your Water Heater Temperature?

Many homeowners wonder if their water heater is set too high. The truth is, most are set higher than necessary. Lowering the temperature can offer several benefits, from energy savings to increased safety.

Understanding Scalding Risks

Water temperatures above 120°F (49°C) can cause scalding burns in seconds, especially for children and the elderly. A typical factory setting is often around 140°F (60°C), which is unnecessarily high for most households. Reducing this temperature to 120°F is a common and recommended practice.

Energy Efficiency Gains

Heating water is a significant portion of a household’s energy bill. By turning down your water heater, you reduce the amount of energy required to keep the water hot. This simple adjustment can lead to noticeable savings on your monthly utility costs.

How to Adjust Your Water Heater Thermostat

Adjusting the thermostat is usually a straightforward process. However, it’s crucial to follow safety precautions and consult your owner’s manual. The exact steps can vary depending on the type and model of your water heater.

Gas Water Heaters

Gas water heaters typically have a control dial located near the bottom of the tank, often behind a small access panel. This dial usually has settings like "Low," "Medium," and "High," or specific temperature markings.

Turn off the gas supply to the water heater. This is a critical safety step.
Remove the access panel to reveal the thermostat.
Adjust the dial to a lower setting. Aim for 120°F (49°C) if a specific temperature is indicated.
Replace the access panel.
Turn the gas supply back on.
Wait for the water to heat up and test the temperature at a faucet.

Electric Water Heaters

Electric water heaters usually have thermostats behind access panels on the side of the tank. There are typically two thermostats, one for the upper heating element and one for the lower.

Turn off the power to the water heater at the circuit breaker. This is essential for preventing electric shock.
Remove the access panels for both thermostats. You may need a screwdriver.
Locate the temperature adjustment screw on each thermostat.
Turn the screws clockwise to decrease the temperature. Use a flathead screwdriver.
Replace the access panels.
Turn the power back on at the circuit breaker.
Allow time for heating and test the water temperature.

Tankless Water Heaters

Tankless water heaters offer more precise digital controls. You can usually adjust the temperature directly through a digital display panel on the unit or via a remote control.

Access the control panel on the unit or the remote.
Navigate to the temperature setting menu.
Use the up/down arrows or buttons to select your desired temperature, typically 120°F (49°C).
Confirm the setting. The unit will automatically adjust.

Important Considerations for Water Heater Settings

Setting your water heater to the right temperature involves more than just turning a dial. Consider these factors to ensure optimal performance and safety.

Finding the Ideal Temperature

While 120°F (49°C) is a good general recommendation, your ideal temperature might vary. Factors like the size of your household and your specific hot water usage patterns can play a role.

Small Households: May find 115°F (46°C) sufficient.
Larger Households: Might prefer 120°F (49°C) to ensure enough hot water.
Dishwashers without Boosters: Some older dishwashers may require hotter water (around 130-140°F) for optimal cleaning. Check your dishwasher’s manual.

Preventing Legionella Bacteria

A common concern with lower water heater temperatures is the potential growth of Legionella bacteria. This bacteria thrives in warm water. However, setting your water heater to 120°F (49°C) is generally considered safe for most households.

To mitigate risks, consider periodically raising the temperature to 140°F (60°C) for a short period (e.g., once a month) if you have individuals with compromised immune systems or if recommended by a plumbing professional. This is often referred to as a "heat cycle."

Testing the Water Temperature

After adjusting the thermostat, it’s vital to test the water temperature at a faucet furthest from the water heater. Run the hot water for a minute or two to get an accurate reading. Use a thermometer if possible to confirm the temperature.

Troubleshooting and When to Call a Professional

If you’re uncomfortable making these adjustments or encounter issues, it’s always best to contact a qualified plumber. They can safely adjust your settings and ensure your water heater is functioning correctly.

Common Issues After Adjustment

Water not hot enough: The thermostat may be set too low, or there could be an issue with the heating element or gas burner.
Water still too hot: The thermostat may be faulty, or you might have residual heat in the tank.
Leaking: If you notice any leaks after adjustment, turn off the water supply and call a professional immediately.

When to Seek Expert Help

You are unsure about any step in the adjustment process.
Your water heater is old or showing signs of damage.
You experience persistent problems with water temperature.
You need to perform maintenance like flushing the tank.

How long does it take for a water heater to cool down after lowering the thermostat?

It typically takes a few hours for the water temperature to significantly decrease after you adjust the thermostat to a lower setting. The exact time depends on the size of your water heater tank and how much hot water is currently stored within it.

Can I set my water heater to 110 degrees Fahrenheit?

Yes, you can set your water heater to 110°F (43°C). This temperature is generally considered safe and can help reduce energy consumption. However, it might not be hot enough for some dishwashers or for households that require very hot water for specific cleaning tasks.

What is the recommended temperature for a water heater to prevent bacteria?

The recommended temperature to prevent bacteria like Legionella from growing in your water heater is generally 120