A traditional water heater keeps 30–50 gallons of water, and preheats it ahead of time. When someone in your home uses hot water, it comes preheated. The tank is then is refilled and reheated.
Conventional water heaters are initially cheaper than tankless options. They usually cost far less at purchase. Installation is also easier, which means that problems with the unit are simpler to fix, and the unit itself is easy to replace.
However, a traditional water heater has its drawbacks. Since it’s heating a set amount of water, regardless of your needs, your utility bill will be higher monthly. Traditional water heaters are also larger than tankless units, which limits where they can be installed; they can’t be installed outdoors, for example. With a traditional heater, there’s also the chance that you can run out of hot water. A conventional water heater also has a shorter life expectancy than a tankless heater, which means you’ll have to replace it more often.
Tankless heaters store no water, and use your home’s power (gas or electricity) to heat water as needed. As such, they don’t take up much space, and end up saving you lots on your utility bills. Tankless electric water heaters and tankless gas water heaters alike take up far less space than a conventional heater; they can be mounted outside if need be. Tankless heaters also last up to twice as long as their conventional counterparts.
The convenience and longevity of the tankless heater comes with its own drawbacks. Tankless water heaters are initially more expensive than conventional heaters, and are more complex to install, resulting in further initial expenses.
When purchasing either type of water heater, you have to gauge your current budget against the benefits and drawbacks of each. If you have the money to spend right now, or if you have a large family, the tankless heater may be for you. However, if you don’t have enough for a tankless heater, or you don’t want to spend too much on installation and replacement, then you may want to stick with the conventional option.