The Difference Between Tank and Tankless Water Heaters

Which Is Right for You?

Today’s water heaters come in all different sizes and efficiencies, but they also come with the word “tank” or “tankless”. Whether you’re in the market for a new model or a replacement, it’s important to know the difference between tank and tankless designs so you can choose the best one for your home.

Operational Differences

While both tank and tankless water heaters do their job and heat your water, they use different methods to do so. In a tank water heater, 30-80 gallons of water is stored in a large tank and is continuously heated by an internal element. This means when you turn on your hot water, you’ll have a reserve of hot water to use.

With a tankless water heater, however, water isn’t stored continuously. Instead, when you turn the water on, the water you need travels into the unit and is heated by a heating element before it’s distributed. You’ll still get hot water on demand, but it won’t be from a stored area.


Because of their design, tankless water heaters cost about three times more than tank water heaters. This is because these models usually require larger gas lines and vent lines than tank models. And when it comes to replacements, a new tank water heater can usually use the same lines as the previous heater; tankless heaters may need new lines, but they also tend to last a few years longer.

Energy Efficiency

On average, tankless water heaters are more efficient than tank water heaters, however, the type of energy you use to heat your home can play a part. According to, gas-fired tankless water heaters tend to have higher flow rates than electric ones and can waste energy if they have a constantly burning pilot light. This means that they be less efficient than their gas-fired tank counterpart.

Another Factor to Consider

Before you decide on a tank or tankless water heater, another factor to consider is power outages. If you live in an area with frequent power outages, you may want to stay away from tankless water heaters. Since tankless models don’t store hot water, you won’t be able to activate the heating element if you don’t have power (meaning you won’t have hot water). If you have a tank heater, however, you’ll have several gallons on hand until you regain power.

If you’re not sure which type of water heater is right for your home, give our water heater experts a call. We’ll help you decide.

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