How to Determine What Size Tankless Water Heater You Need For Your Home

Tankless Water Heater
So, your traditional hot water heater finally kicked the bucket. It’s OK! All good things come to an end at some point.  This is probably leaving you with some tough decisions to make.

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So, your traditional hot water heater finally kicked the bucket. It’s OK! All good things come to an end at some point.  This is probably leaving you with some tough decisions to make. Do you have another traditional water heater installed? Or do you take the plunge and switch over to a tankless water heating system? With so many sizes and models to research, it can be difficult to know which one will best suit your needs.  Here are a few important factors to look at before you make your decision.

The Number of Bathrooms in Your Home

One of the most important factors you need to consider when choosing a tankless water heater is the number of bathrooms in your home. This is important because each bathroom has it’s own fixtures, such as sink, toilet, and shower.  If you have two or more bathrooms in the house, you will need to add up something called the flow rate of all the fixtures. This will help you determine your peak hot water demand. If you have two bathrooms, each with a sink and shower, the peak hot water demand would be around 4.5 gallons per minute. 

Bathroom Water Heater

How Many People in Your Home

We all know that teenagers are notorious for hogging the bathroom, especially the shower. They often leave younger siblings to take a lukewarm or even cold showers! Everyone in the family should be able to have a hot shower when they need it.  The number of people in your home also determines what size tankless system you need.  If you only have two people in your home, you won’t need as big of a tankless system as you might think. However, if you have a larger family, it is more likely that multiple fixtures will be in use at the same time. So, if: Dad is cleaning the dishes, Mom is showering, little Jonny is brushing his teeth, and little Debbie is also brushing her teeth, then you will have to consider the flow rate of all the fixtures in your home. This again will help you determine your peak hot water demand.

The Climate in Which You Live

 Tankless water heaters are a great option for homes located in all types of climates. However, if your like us here at T.J. Huggard Plumbing, and live in a colder climate, there are some other factors to consider. If you live in an area that tends to have really cold winters (here in Utah), we recommend considering a gas tankless hot water heater.  This is because gas tankless systems work better than their electric counterparts in colder climates. They produce a high flow rate which gives you the hot water you need during winter. You will also need a bigger system to help keep your pipes from freezing.

 Lehi Utah in Winter

The Temperature Rise

Another important thing to know about is something called Temperature rise. Temperature rise is the difference between the cold water temperature and the temperature you want your hot water to be. The higher the rise, the hotter the water you will need. For example, if your incoming cold water is 50 degrees, and you want hot water to be 120 degrees, your temperature rise would be 70 degrees. If your water is always really cold, you may need a bigger tankless system to counter the rise.

Water Heater Temperature

Calculating Tankless Sizing

Now it’s time for the math part for determining the tankless size you will need. To start, multiply the number of bathrooms by three. This gives you the gallons per minute flow rate that you will need. Next, multiply the gallons per minute by 60 to get your maximum flow rate per hour. Lastly, divide that number by 1000 to get the kilowatts required.

Benefits of Switching to a Tankless Hot Water Heater.

  • Improved energy efficiency
  • Lower utility bills
  • Extended life span
  • Plentiful hot water
  • Saves space in your home
  • Less Maintenance

We hope this gets you started on your search for the right size tankless water heater. If you ever have any questions or need plumbing services in the greater Salt Lake City area, be sure to give us a call!

Benefits of a Water Softener

The Benefits of Installing a Water Softener in Your Home

When water contains high amounts of dissolved calcium and magnesium, it can become a source of discomfort or inconvenience. This is what we call hard water. If you’ve noticed a foggy residue on your drinking glasses after the dishwasher or your hands feeling slimy after washing with soap, your home could have hard water.