If you are looking to upgrade your water heater, especially if you don’t use a ton of hot water, you might want to consider a solution many people have already taken – moving to tank-less or instant water systems. These systems tend to cost more up front but are far more efficient and use far less energy than normal tank water heaters. How does the technology work, you ask? What is it that makes them so efficient and why where they not an option before? Let’s take a look inside the instant hot water heater and see what it is that makes them able to offer such value.

Traditional Tank Heaters

First you have to understand how traditional tank based heating systems work. These systems work by piping water into a large collection tank where it is stored and heated. Then when you need hot water it flows out of the tank through the pipes and to where you need it. However in order to have instant hot water the tank has to be constantly heated to keep the water warm, even when you are not using the water, otherwise the water would cool through natural heat loss. This requires a lot of space, and energy to maintain even when you don’t need hot water, and it means a long wait time as you have to wait for the whole tank to heat up again to get more hot water if you drain it. This is why you get cold showers after everyone else in the house has had a shower before you.

On Demand Heaters

The major difference is that these water heating systems have no tank. Recent advances have made it possible to super heat coils in the water heater very quickly. This activates by water pouring into the system when you use the tap. The water passes through these coils heating to the set temperature and then flows out to where you need it. There is very little wait time and because the reheat is instant there is no need for a large tank of water. With this technology, the lack of tank and no need to constantly be heating this type of water heater the most energy efficient on the market.

Types of Tank-less

There are four types of tank-less water heaters divided into two categories; power and placement. Power is what is used to heat the coils, either electric or gas. Gas powered heaters are usually more powerful in that they can heat quicker so you get a better flow and water capacity before you out pace how fast it can heat the water. Electrics tend to be easier and cheaper to install and use though since you don’t need a gas line, or have to pay gas and electricity. Placement is either point of use, or whole house instant water heaters. Because they are so much smaller than regular heating systems and only used on demand they can be put close to point of use for hot water, hence the name. These types are usually electric and useful when you need simultaneous hot water lines. Whole house heating systems are usually gas and designed to heat large areas, though because of the travel time through the pipes can cause a lag. 

Enjoyed this article? Join 40,000+ subscribers to the ZME Science newsletter. Subscribe now!