Tankless water heaters heat the water as soon as the tap is turned on.
Tank water heaters heat the water in advance in a large storage tank.
Tankless water heaters are more energy efficient, but tank water heaters are more economical and easier to install.
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Tankless vs.
The heating source consists of two heat exchangers located in the center of the water heater.
Tankless water heaters are sometimes called on-demand, instant, or instantaneous water heaters.
Bothtypes of water heatersare tankless.
40-, 50, 55-, or 80-gallon tank.
The heating source is located at the bottom of the tank.
The water is heated much like a pot of water is heated on a stove.
The water is kept constantly hot.
When hot water is used, new cold water enters the tank and the heating source automatically activates.
When the water has reached the set temperature, the heating source turns off.
Performance
Tankless water heaters generally have a flow rate of 2 to 5 GPM.
For gas tankless water heaters, a 5 GPM unit is needed to raise the water temperature by 70oF.
Electric tankless water heaters are slower, at about 2 GPM for the same temperature rise.
Tank water heaters put out a lot of hot water at a fast rate.
A tankless water heater moves the water slowly through its heat exchanger to heat it.
This means that hot water is kept at-ready when no one is using watereven during long periods.
Tank water heaters are internally insulated.
it’s possible for you to also wrap inexpensive water heater insulation over the tank.
Like a coat for your water heater, it adds up to R-10 insulating values.
Turn down your water heater to between 120F and 140F.
Not only does this save energy but it also reduces the chance of scalding.
Tank water heaters are largely self-maintaining.
Best for Maintenance
Tankless and tank water heaters require roughly the same amount of maintenance.
Lifespan
A tankless water heater can last up to 20 years, if well-maintained.
A tankwater heater will lastfrom eight to 12 years, depending on the level of maintenance.
It’s probably time toreplace your tanks water heaterif leaks have developed from the tank.
Installation
A licensed plumber and/or electrician should install a tankless water heater.
Nearly every plumber can install a tank water heater.
Best for Installation
A tank water heater is easier for installation than a tankless water heater.
Cost
A tankless water heater costs from $1,200 to $4,250 or more to install.
Converting from a tank water heater to a tankless water heater will cost more.
Thebest tankless water heaterheats only as much water as is needed: no more, no less.
A tank water heater costs from $975 to $2,400 to install.
Tank water heaters are prevalent and are found in a wide range of prices.
Appearance
Tankless water heaters are relatively small, flat, and wall-mounted.
Tank water heaters have a characteristic tall, cylindrical appearance.
The tank is about 60 inches high and between 20 and 24 inches in diameter.
Best for Appearance
Tankless water heaters are slimmer and more compact than tank water heaters.
Tankless vs.
Tank water heaters are economical to purchase and install.
They do use more energy than tankless heaters but they can reliably deliver hot water in large quantities.
But it may be worth switching if long-term energy efficiency is a concern.
Sizing a New Water Heater.
Do-It-Yourself Savings Project: Lower Water Heating Temperature.
