How to Adjust Your Water Heater Temperature Setting

Water heaters are an essential part of any modern house. Gas water heaters and electric water heaters provide us with warm water throughout the day, making our lives easier and more comfortable. However, not everyone is aware that adjusting the hot water heater temperature is a critical task that can affect the safety and efficiency of your home’s plumbing system. In this blog post, Jarboe’s Heating, Cooling & Plumbing will discuss why adjusting your water heater temperature is essential, and go over a step-by-step guide on how to do it.

Why Adjusting Your Water Heater Temperature Is Essential

Most hot water heaters come with a default setting of 140°F. High temperatures are used to prevent bacterial growth that can lead to Legionnaires’ disease and other problems. While this may seem like a comfortable temperature to have your water heater set to, the hotter water can be too hot for some people. This hot water can even be dangerous in certain situations. Here are some reasons why you may want to adjust your water heater temperature setting:


Having a water heater that is too hot can be dangerous, especially if you have small children or elderly family members. Scalding from hot water is a common issue that occurs when the water temperature is too high, causing severe burns and even third-degree burns. In extreme cases, it can even be fatal.

Energy Efficiency 

Water heating accounts for a large chunk of the typical home’s energy bills. By adjusting your water heater’ thermostat to a lower setting, you can reduce your energy usage, and in turn, save money on your utility bill each month.

Water Quality  

Water that is heated to 140°F is more prone to causing mineral deposits, corrosion, and scaling in your plumbing system. This can lead to a reduction in water quality, and eventually, damage to your pipes and appliances.

How to Adjust Water Heater Temperature Control

Now that you understand why it’s essential to adjust your water heater’s temperature setting, let’s go over how to set your water heater’s thermostat. Here is a step-by-step guide to help you get the job done quickly and safely:

Step 1: Turn off the Power 

The first step before adjusting your water heater’s temperature is to turn off the power. If you have an electric water heater, you’ll need to locate the circuit breaker or fuse box and turn off the breaker or remove the fuse that controls the water heater. If it’s a gas water heater, you’ll need to find the on/off switch or valve to shut off the gas supply.

Step 2: Locate the Thermostat 

Next, locate the thermostat on your water heater. It may be a small temperature dial or a digital display located on the outside of the tank if you have an older hot water heater. For newer-model gas water heaters and electric water heaters, the thermostat is usually located behind an access panel cover, which you’ll need to remove. Most electric water heaters have two thermostats – one for the upper heating element and one for the lower. You’ll need to adjust both thermostats if you want to change the temperature for the entire tank.

For tankless hot water heaters, the thermostat is typically positioned close to the unit’s heat exchanger, which is where the heating process takes place. This location allows the temperature of the water to be accurately regulated, ensuring that it is delivered at a consistently desirable temperature. Additionally, many tankless water heaters come with digital or remote thermostats that allow for easy temperature adjustment and monitoring.

Step 3: Adjust the Temperature 

Using a flathead screwdriver or your hand, adjust the thermostat or temperature dial to the desired temperature setting. When you adjust the temperature, the recommended water temperature setting is 120°F. However, if you have a dishwasher that is not equipped with its own booster heater, you may want to set the temperature closer to 140°F.

Step 4: Restore Power

Once you adjust the temperature, turn the power back on by flipping the circuit breaker or turning on the gas valve. Wait for a few minutes to make sure the water in your tank has heated to the right temperature before using it.

Is My Water Heater Thermostat Bad?  

Your home’s water heater is responsible for providing hot water for your daily needs, from showering to washing dishes. However, if something goes wrong with your water heater, it can be a major inconvenience and impact your daily routine.

One of the most crucial components of your water heater is the thermostat. The thermostat regulates the temperature of the water and ensures that it stays within a safe temperature range. If your water heater thermostat is faulty, you may experience problems with your hot water supply. In this section, we will explain how you can tell if your water heater thermostat is bad.

  • You may notice that the temperature of your water is not consistent. If the water is not heating up to the desired temperature or is overheating, this may be an indication that your thermostat is not functioning properly. The thermostat may be failing to regulate the temperature of the water, resulting in uneven heating and fluctuations in water temperature.

  • If you notice that your water heater is producing insufficient hot water or water is not the same temperature as usual, this may also be a sign that your thermostat is not working correctly. This problem occurs because the thermostat is unable to measure the water temperature accurately, causing the water to be heated inadequately. This often occurs when the thermostat sensor is not properly installed.

  • You may notice that your water heater is constantly switching on and off, indicating that the thermostat is struggling to maintain a steady temperature. This can occur when the thermostat is clogged with debris or mineral buildup, which hinders its ability to detect the water temperature accurately.

  • If you have an older hot water heater, it is essential to consider the lifespan of the thermostat. Over time, the continual use of the thermostat can cause it to wear out and malfunction. If your water heater is over ten years old and you notice symptoms of a faulty thermostat, it may be time to replace it entirely.

Get Help Setting Your Hot Water Temperature

By following these simple steps, you can make sure that your water heater is set to a safe and efficient temperature. Remember to check the temperature setting periodically throughout the year since your water usage may vary depending on the season. If you’re not comfortable adjusting your water heater’s temperature yourself, don’t hesitate to call in a professional plumber for Louisville water heater repair. They have the knowledge and expertise to ensure that your water heater is set up correctly. At Jarboe’s, we have a team of experienced plumbers who can assist you with any water heater issues you may have. Get in touch with us today!

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