What is a tankless water heater? As the name implies, these devices heat the water without a tank. They use a heating element to heat the water directly as the fluid runs through it. As a result, these devices can provide hot water only as it is needed, and there is no energy loss from keeping the water in a tank hot.
When you turn on the hot water, cold water runs through a pipe into the device. Then a gas burner or electric heating element in the unit raises the temperature of the water. So, you can get as much hot water as you need, without waiting for the storage tank to refill. However, because of the way tankless units heat the water, they have a more limited flow rate of about two to five gallons per minute. Gas tankless heaters are able to produce more water than electric ones.
But even gas tankless heaters may have trouble providing enough water if there is a real surge in demand, such as running the shower and dishwasher at the same time. The way to handle this problem is to install more than one tankless heater. You can even install a tankless heater for an individual appliance that uses a lot of water, such as a washing machine.
If you use 40 gallons of water or less a day, a tankless heater can save you up to one-third the energy cost of a regular water heater. If you use 85 plus gallons a day, you can save up to 14 percent on your energy bill compared to a regular heater. And, if you install a tankless heater at every fixture that uses hot water, you can cut your water heater bill in half compared to a conventional water heater. A family can save about $100 a year with an Energy Star tankless heater.
Tankless heaters do cost more than conventional ones, but consumers can end up saving money because the tankless heaters last longer and are cheaper to operate. Most of the tankless heaters last about 20 years. In addition, it is much easier to replace their parts, which can also add life to the heater. By contrast, conventional heaters last only about 10 to 15 years.
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