If you are replacing your water heater and looking for an energy efficient option, you may be thinking about a tankless version.

(You can read about the advantages and disadvantages of both types of water heaters in our blog Tankless vs. Traditional Water Heaters.)

But there are dozens of different sizes and models available, so how do you choose the best tankless water heater for your home? Here are two key factors to consider before making your final choice.

Fuel Type

The first step in finding the best tankless water heater for your home is to determine the fuel type you need. You have two options here in the Atlanta area:

  • Natural gas
  • Electric

If you are going with an electric water heater, you must ensure that:

  • You have the proper voltage outlet
  • Your home can support the amperage draw of the new water heater
  • Your water heater is on its own circuit.

If you decide natural gas is the way to go, you will need to make sure the gas supply line will support your new water heater. The gas supply line to your old water heater may not be sufficient.

You also want to make sure you have adequate venting for your new gas tankless water heater. This is where you would need to retrofit your home if you previously had a traditional, tank-style water heater.

Flow Rate/Demand

Running hot water from a faucet uses less water than a dishwasher or shower (measured in GPM or gallons per minute.)

You will need to add up the flow rates of each fixture you want to use simultaneously and find a tankless water heater that will be able to keep up with that demand.

For example, some lower-end tankless water heaters may be able to provide adequate hot water for one shower at a time, but falter if the dishwasher or washing machine is also running while you are taking a shower.

You can determine the best tankless water heater for your home by looking at three things:

  • Temperature rise
  • Flow rate
  • Incoming water temperature

Let’s say that you want to be able to take a shower while your dishwasher is running (a reasonable request). The flow rate of your dishwasher is 1.0 GPM, and your showerhead is 1.5 GPM. The incoming water temperature in the Atlanta area is usually around 60° F.

You probably want to shoot for hot water that is around 110-115°F. This means you need a tankless water heater that will raise the water temperature at least 50° F at 2.5 GPM.

Keep in mind, the higher the demand for water (the more fixtures requiring hot water simultaneously), the lower the temperature increase will be. So doing this little bit of math ahead of time will save you from cold showers.

The Best Tankless Water Heater

The best tankless water heater is the one that’s right for your home. Every family’s hot water use and every home’s plumbing is a bit different. But if you get the right tankless water heater, you’ll never run out of hot water again!

Need help selecting the tankless water heater that’s best for your Atlanta-area home? Our plumbing experts are ready and willing to help.

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