A hot bath or steaming shower is one of life’s pleasures. Whether it’s after a long weekend hike in the hills, a 20-min run at lunch, or simply just to relax and unwind in the evening, there’s nothing quite like a good soak.
But if your heating system uses any type of hot water storage cylinder, it’s vital that you keep it at the correct temperature: 60-65 degrees Celsius. And here’s why...
It’s healthiest
The most important reason to make sure your cylinder thermostat is doing its job properly is your health. Because keeping it at the recommended hot water tank temperature is a sure-fire way to ward off bacterial nasties.
Legionella bacteria thrives at temperatures between 25 and 45 degrees Celsius – but 60°C and above is enough to kill the bacteria. Legionella bacteria is what causes the type of pneumonia we call Legionnaires’ diseases – and it can be very serious. But at 60°C and above? You’re good to go and your household will have nothing to worry about.
But not too hot
Storing hot water at between 60 and 65 degrees Celsius is not only hot enough to ward off dangerous bacteria, it also means you’re not paying to overheat the water. So if your thermostat’s up to scratch, you could be saving money, too. It also helps to avoid scolding-hot water. If your stored hot water is consistently kept between 60-65°C, by the time it reaches your taps (by way of your water system), it should have cooled from down to around 35-46°C. And that should be just right for piping hot, but safely so.
Control your hot water via our smart home app
With our smart thermostats you can also control your hot water wherever you are via the Hive app. So if you’re expecting to be away, you can easily adjust the schedule so you don’t pay to heat water you won’t need.
It also has a quick boost functionality that works for both your hot water and room temperature. So if there’s a chill in the air or you fancy a longer, more luxurious bath, a quick tap is all you need. And you don’t have to worry about turning it off because it will do that automatically.
Interested to find out more? Check out our smart thermostats and we’ll get the ball rolling.
Skip to content
- About Us
- Meet the Team
- Videos
- Service Area
- Employment
- Caccia Care Club
- Services
- Emergency Plumbing
- Boiler Repairs
- Apartment Plumbing
- Faucets & Fixture Services
- Gas Line Repairs & Leak Detection
- Repiping
- Septic Tank Repair
- Slab Leak Repairs
- Trenchless Sewer Replacement
- Water Filtration Systems
- Water Heaters
- Tankless Water Heaters
- Backflow Testing Certification
- Commercial TI
- Drain Cleaning
- Garbage Disposals
- Hydrojetting
- Bathroom Remodeling
- Sewer Line Repair Services
- Sump Pumps
- Clogged Toilet Repairs
- Water Softeners
- Water Heater Installation
- Water Heater Repair
- Reviews
- Coupons
- Blog
- Contact Us
What Temperature Should a Hot Water Heater be Set At?
What is the Right Water Heater Temperature?
You probably don’t think too much about your water heater, unless you take a shower and run out of hot water. Or worse, if the water is too hot and causes scalding. You can adjust the temperature of your water heater, but should you?
While you may think water heaters have a standard recommended temperature, it’s not that simple. Some manufacturers factory-set their water heaters at 120°F (49°C), while others are set to a default 140°F (60°C). The Department of Energy recommends setting a water heater to 120 degrees to save on energy costs, and the Consumer Product Safety Commission advises the same temperature to prevent scalding. OSHA (the Occupational Safety and Health Administration) recommends setting the temperature to at least 122 degrees to help prevent the growth of harmful bacteria.
Should I Change the Water Heater Temperature?
There are several factors you may want to consider to determine the most appropriate water heater temperature for your home:
- Safety
- Cost
- Energy efficiency
Hot Water Kills Harmful Pathogens
Legionella, the bacteria that causes Legionnaires' disease, can become a health concern when it grows in home water systems. Water heaters maintained below 140 degrees and that contain scale and sediment may foster Legionella growth, according to OSHA. Luckily, most healthy people exposed to Legionella do not get sick, but before you decide to turn up the temperature dial on your water heater, read on.
Hot Water Can Scald
Hot tap water is a primary cause of burn injuries and deaths. Scald burns can be a real hazard, especially if you have young children or senior adults in the home. These two age groups are at the highest risk for scalds: Young children, because their skin is thinner, and the elderly because they can be less sensitive to temperature and may be slower to respond to scalding water.
The CPSC warns that adults may suffer third-degree burns if exposed to 150-degree water for as little as two seconds. Burns can also occur with a six-second exposure to 140-degree water or with a 30-second exposure to 130-degree water. Even if the temperature is 120 degrees, a five-minute exposure could result in third-degree burns.
Minimize Risk with Anti-Scald Devices
So how do you negotiate the opposing risks of bacteria growth and potential scalding? Newer homes typically have anti-scald devices, but if you live in an older home, you can add anti-scald guards and devices to showerheads and tub spouts to help avoid dangerously hot water. Talk to a plumber about installing a thermostatic mixing valve (also called tempering or anti-scald valve) that limits the max temperature coming out of your water heater.
Will Changing the Water Heater Temperature Save Money?
The temperature at which you set your water heater can definitely make a difference in your home energy bill.
The water heater is one of the largest single costs on a home energy bill, with estimates ranging from 17 to more than 25 percent of your monthly energy costs.
According to the Energy Department, turning down your water heater temperature significantly reduces the costs of standby losses – heat lost from the water heater into the surrounding area. Set at 140 degrees or more, your water heater can waste anywhere from $36 to $61 annually in standby heat losses. More savings can be had by using a lower temperature for tasks including clothes washing, taking showers, and dishwashing. The Energy Department estimates these consumption savings may amount to more than $400 per year.
What is My Water Heater Temperature?
On most tank water heaters, and some tankless, you won’t be able to tell the temperature just by looking at the temperature dial, as most are simply marked from “Low” to “Hot” (or “Very Hot.”) If you have your water heater manual, the default temperature should be noted. If not, simply search the internet for the brand and type of water heater and its “default temperature.”
However, the water heater’s default temperature isn’t necessarily the temperature that is coming out of your taps. To be safe, check your tap water temperature.
How to Check Your Tap Water Temperature
- Do not use your hot water for at least two hours before testing. If you have a tankless water heater, you can skip this step.
- Let the hot water run for at least three minutes. Test the temperature with a candy, meat, or water thermometer.
- Adjust the temperature on your water heater thermostat. Repeat steps 2 and 3 until you reach the desired temperature.
- Wait a full day to allow the water temperature to change, then test again. You can skip this step for a tankless water heater.
Pro Tip: When you find the temperature you want, mark the spot on your water heater's temperature dial with a permanent marker.
Find the Right Water Heater Temperature
The “right” temperature for your water heater is really an individual one – for your own level of comfort, any safety concerns, your monthly bill, and energy efficiency concerns.
Home Warranty Coverage for Water Heaters
Regular maintenance of your water heater can help prevent breakdowns and may even extend the life of the unit.
The most diligent care, however, may not be enough to prevent a problem with your water heater. A home warranty can protect your budget from unexpected repair or replacement costs when appliances like your water heater stop working. Learn about the many other appliances and home systems you can cover with a home warranty plan, or get a quote today.