Understanding Plumbing Basics
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Understanding Plumbing Basics

As a new homeowner, I can tell you that things aren't always as simple as they appear. I started thinking about it a few years ago, and I realized that there were some serious problems with our plumbing system. We had issues with drains working correctly and toilets flushing like they should, so I started focusing more heavily on understanding the basics of our plumbing system. Within a few short months the entire system was operating more fluidly because of a few changes that I made, so I wanted to create a blog all about my journey. Check out these articles to learn more about the plumbing basics.


Understanding Plumbing Basics

The Highs And Lows Of Your Water Heater's Thermostat

Jorge Alexander

Every hot water heater has one – that little knob which lets you adjust the temperature of the water being heated inside. Some simply read hotter and warmer with an accompanying directional arrow, allowing you to choose whether to raise or lower the temperature. Others are a bit more sophisticated, and give actual temperature choices in Fahrenheit, like 110, 120, and so on. The big conundrum facing you now is how high or low should you set your system?

Finding That Delicate Balance

The temperature mystery all boils down to energy efficiency and safety, and here's why:

  • The lower the temperature of the water heater's thermostat, the greater the savings in energy cost.  Your water heater doesn't have to work as hard to keep the water at a lower temperature, which is more energy efficient.
  • The lower the temperature, the safer it is for children and the elderly. The majority of burn incidents involve the elderly and children under the age of 5, often from hot tap water.  Because of this, the US consumer Product Safety Commission recommends water heaters be set at 120 degrees.

But what if you need your water to be hotter? Dishwashers need to have a water temperature of 130 to 140 degrees to properly kill germs during the rinse cycle. Also, the threat of Legionella bacteria prompts some homeowners to set the thermostat higher. This bacteria requires a minimum temperature of 140 degrees for 32 minutes to be completely killed. Also, some people prefer to wash their laundry whites in hotter water to get their clothes looking bright, clean and white.

Water temperatures hovering around 140 degrees have horrifying consequences for children and the elderly, who can receive 3rd degree burns in only 5 seconds.  Remember, 3rd degree burns are serious – the entire skin depth is destroyed. Even if you lower your water to 130 degrees, it only takes 30 seconds to burn that badly. At that temperature, some bacteria are not affected anyway.

Determine Your Priorities

The best way to choose the right temperature for your household is to look at your needs and your liabilities. If you have children, it's better to keep it set around 120 degrees to be safe. Check the feel of the hot water before allowing small children to wash hands or bathe. If you're still concerned about germs, make sure your dishwasher is a newer model. Many have a feature that boosts the temperature of the water inside solely during the rinse cycle to kill germs.

If you do not have children in your home and you feel confident that you can stay safe around hotter water, setting your water heater thermostat higher might be right for you. For more information about changing your water heater settings, contact a residential plumber near you.