Your water heater is designed to always heat water to the same temperature, which means that you usually don’t ever need to worry about adjusting it. However, there are times when you may find that your water isn’t hot enough or is way too hot. In case this ever happens, here is a full overview of how to adjust the temperature on different types of water heaters and also recommendations for what temperature your hot water should be.

What Temperature Should a Water Heater Be Set At?

Most water heaters are designed to operate safely at temperatures between 120 and 160 degrees. Many tank-style units also have a low-temperature setting where the unit will only heat up the water to around 90 to 100 degrees. While this is great for minimizing energy waste, the unit should never be left on this setting any time you’re home and using your hot water.

If the water inside the tank isn’t heated to at least 120 degrees, it can quickly result in harmful bacteria starting to grow. The biggest risk is Legionella—the bacteria that causes Legionnaire’s disease—as this thrives in warm water. Making sure your water heater is always set to at least 120 degrees minimizes this risk, as the water should be hot enough to kill any bacteria.

Even though most units will go up to 160 degrees, you really shouldn’t ever set the temperature higher than 140 degrees in order to reduce the risk of scalding. The EPA recommendation is to always leave your water heater set to 120 degrees. This is both so that the unit loses less energy and also to prevent possible scalding. OSHA, on the other hand, recommends setting your water heater to 140 degrees in order to aid with cleaning and sanitation.

Anything between 120 and 140 degrees is within the safe range, which means it really all comes down to a matter of personal preference. If you have younger children in the house, you are always better to have your water heater set to 120 degrees to prevent scalding. If there are no kids in the home or your children are older, we would usually recommend turning the unit up to 130 or 140 degrees.

It is also usually a good idea to turn your water heater up to the next highest setting during the winter. Your water lines are always colder during the winter, and this can cause your hot water to cool down quite a bit as it travels from the water heater to your sink or shower. If you don’t turn your water heater up for the winter, this issue can often lead to your water never feeling quite hot enough.

How to Adjust the Temperature on a Gas Water Heater

If you have a tank-style gas water heater, the temperature control knob will be located somewhere near the base of the unit. Adjusting the temperature on this type of unit only takes a second and is simply a matter of turning the knob to the higher or lower setting. The only issue is that most of these units use numbers and symbols for the different settings instead of listing the actual temperatures. This means that you first need to know what temperature each setting corresponds to so that you don’t accidentally turn the unit up too high or down too low. Luckily, these symbols are usually fairly standard across most all units.

The first setting just past the “Off” setting is usually either labeled as “Low” or marked with a solid circle, and this setting corresponds to between 90 and 100 degrees. The next highest setting is usually either labeled as “Hot” or with a triangle, and this setting should correspond to 120 degrees. From there, you will typically see three higher settings marked either as 1, 2, and 3 or A, B, and C that correspond to 130, 140, and 150 degrees, respectively. The highest setting corresponds to 160 degrees and is usually labeled as “Very Hot.”

If you have an older water heater, it will most likely also have a “Pilot” setting that is used whenever you need to relight the pilot light. Most newer units won’t have this setting since they typically use an electronic igniter instead of a standing pilot light. If your unit has a pilot light, it may also have a “Vacation” setting. When set to Vacation mode, the unit won’t turn on and waste energy while you’re away. However, gas will still flow to the pilot light so that it stays lit.

How to Adjust the Temperature on an Electric Water Heater

Adjusting the temperature on a tank-style electric water heater is mostly the same as it is for gas units. However, electric units typically have the temperature control hidden behind an access panel located near the bottom of the unit, and you will usually need to remove a few screws to take the cover to the panel off. There will also usually be some insulation that you need to remove before you can access the temperature control. From there, all you need to do is adjust the control knob up or down to the desired temperature or corresponding symbol. Once you’re done, make sure you replace the insulation to prevent heat loss and energy waste.

How to Adjust the Temperature on a Tankless Water Heater

Raising or lowering the temperature on a tankless water heater is even easier than on any other type of unit. This is because most tankless units have a digital display that shows you exactly what the temperature is set to. To increase or decrease the water temperature, all you need to do is push the up or down arrows until the display shows your desired temperature.

How to Measure Your Water Temperature

All water heaters can occasionally experience issues that cause them to heat to a higher or lower temperature. If you ever find that your water suddenly feels hotter or colder than normal, we would recommend measuring the temperature as this will help you to determine if your water heater is working correctly.

To measure your hot water temperature, first, turn the hot water on at a sink as high as it will go. Let the water run for at least 30 seconds to ensure that it is fully hot, and then use a kitchen thermometer to measure the temperature. If the temperature isn’t the same as what your water heater is set to, it is a good idea to have the unit inspected to determine why it is heating too much or too little.

At Meade’s Heating and Air, our team can help with any water heater issues you may be having. We repair and service all water heater models, and we also install both tankless and traditional units. Our team of certified technicians also specializes in ductwork and indoor air quality services, as well as all types of heating and cooling repairs, maintenance, and installation. If you need any water heater or HVAC service in the Sterling area, give us a call today.

Meade's Heating and Air

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