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Should I Raise My Water Heater Temperature?

Do you find that your home’s water just doesn’t feel as warm as it should? This may leave you wondering whether or not you should turn up the dial on your water heater temperature. Here is everything you need to know about raising your water heater temperature, brought to you by the plumbing experts at Bonney.

Cold Weather and Water Heater Temperatures

Should I raise my water heater temperature in the winter? While there is no way to know for sure without taking a look at your unit, most winter water heater troubles are solved with a simple temperature increase. 

Any time the outdoor temperature drops, you could potentially feel the impacts on your water heater. This happens for two reasons: colder water input and a lower temperature environment. 

  • Colder water input: The water entering your unit will be much colder in the winter, meaning that your water heater will have to bridge a wider temperature difference. 
  • Lower temperature environment: Your pipes, tank, and home environment will also be colder, which can naturally impact the temperature of your water heater. 

Every water heater, individual preference, and home plumbing system is different. However, if your water heater tank functioning has become impacted by the winter weather, you can consider raising the temperature. Read more on this process below and its impacts below. 

Pro Tip: While a higher water heater temperature may solve your immediate unit troubles, they will not protect your unit from the impacts of the winter season. Each time cold water hits the steel of your unit, the metal contracts internally, which is not visible from the outside of the tank. Keeping up with your maintenance is essential to winter water heater care. 

Summer Weather and Water Heater Temperatures

Should I raise my water heater temperature in the spring or summer? The short answer is no. In fact, the warmer seasons are often the time to turn down your water heater temperature following any cold-weather increases. 

If you find that you do not have sufficient hot water in the warmer months, this is often a sign of trouble with your unit. Your water heater may be due for maintenance, repair, or replacement. In this case, consider contacting your local experts at Bonney for support.

Tankless Water Heaters

Should I raise the temperature on my tankless water heater? While this question is a bit more complex, the answer is often no. Tankless units heat water on demand. These systems are preset to a temperature that will give your home a consistent flow of hot water. Many homeowners find their tankless hot water flow is already weaker than the output produced by standard tank units, especially in the winter.

This is because the colder water requires your unit to heat a larger differential. In the summer, your water input might be ~50℉, while in the winter it might be ~35℉. This 15℉ difference causes tankless units to slow the flow of water, allowing it to raise the temperature from 35℉ to 120℉. Meanwhile, summer temperatures only require the unit to raise the temperature from ~55℉ to 120℉. The harder your tankless water heater has to work, the less volume of hot water it will produce. 

When you raise this temperature beyond 120℉, your unit has to work even harder to keep up. Ultimately, this can drop your hot water flow down to a trickle. While this process is technically possible, it may not be feasible for your home. 

How to Raise Water Heater Temperature

Most homeowners can raise the water heater temperature themselves. To do this, simply turn the dial on your water heater up by one notch or letter. Each notch often signifies a ~10℉ temperature increase—though you should read the specifics in your owner’s manual.  Assuming your water heater is in good working condition, this will successfully boost your water temperature. 

Caution: Be Mindful of Potentially Scalding Water

It bears repeating that after raising your water heater temperature to offset winter seasonal changes, you must lower it back down when the weather becomes warmer. You also must ensure that you do not raise your temperature more than what is needed to combat the cold weather. Otherwise, you may find yourself with scalding water, which can burn you within seconds. This is especially true for any vulnerable members of your household, such as children, elderly adults, and those with sensitive skin. The U.S. Consumer Product Safety Commission (CPSC) recommends maintaining a water heater temperature of 120℉, citing the following stats:

  • Most adults will suffer third-degree burns if exposed to 150℉ water for two seconds.
  • Burns can occur with a six-second exposure to 140℉ water,
  • Burns can occur with 30-second exposure to 130℉ water. 
  • Even at 120℉, a five-minute exposure could result in third-degree burns.

Again, these statistics apply to most adults. Every individual is different, and the statistics change across demographics. 

Water Heater Settings vs. Fixture Output

Conversely, it is also important to note that the temperature settings on your water heater do not necessarily reflect the temperature of the water you are getting out of your shower or sink. Here are some of the common reasons for this difference:

  • Water may cool slightly when running from your tank to your faucet. This is especially true when your house is built on a slab foundation. Your pipes will run hot water under and through the cold foundation concrete.
  • Your water output will vary based on your shower, sink, or faucet configurations. 
  • Sinks and showers all have both hot and cold water pipes that mix together Your resulting hot water will be cooled down when it mixes with the cold pipe’s water supply.
  • Showers, sinks, and other fixtures may have heat regulators or anti-scald devices that limit the amount of hot water you are receiving. 

To read the exact temperature of your running water, the CSPC recommends using a food-grade thermometer. The temperature reading is ALWAYS accurate. However, some water heaters are coolest in the morning or at the end of a “sleep” cycle. 

What is a sleep cycle? Your water heater tank does not reheat at every degree drop. When your control valve is set at ~120℉, it will heat to 120℉ (or maybe up to 122℉-123℉) before shutting off (or “sleeping”). The unit will set/sleep until the hot water is used or it naturally drops about 8-10 degrees, then it turns back on. This is why you might have to turn the shower valve handle a little more to the hot side in the morning. Whereas if someone took a shower 30 minutes before you did and the tank is fully recovered, you might get water that feels a bit warmer. 

If you still feel like your water is not getting hot, you may have a plumbing problem or an issue with your water heater—in which case, you can contact the experts at Bonney for support. 

Bonney: Water Heater Service Near Me

If you have any questions about your water heater adjustment, give the professional plumbers at Bonney or Boyd a call. You can also ask your Bonney expert all of your water heater questions during your next plumbing maintenance visit, service visit, or virtual plumbing consultation. We provide world-class plumbing solutions—including water heater repair, replacement, and maintenance—to the greater Sacramento area. This includes Citrus Heights, Folsom, Carmichael, Rancho Cordova, Gold River, Fair Oaks, Roseville, and beyond! You can make your appointment here online to get started today!