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How Does Tankless Heater Work?

Jennifer Hansen
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by Jennifer Hansen

Tankless water heaters are coming into mainstream from overseas, where they have been used as a green resource in both Europe and Japan for years. The U.S., with a new and necessary emphasis on environmentally friendly living within the past decade, has now started providing them in households across the country.

Not to be outdone by the environment, another attractive aspect of the tankless water heater is the money it can save over time, though you might not be sure how. They come with a list of pros and cons, but those who are pondering whether or not to install one should be asking themselves the most important question of all: how do they work?

In order to decide if a tankless heater is right for you, your home, and your family, you’ll want to brush up on what makes it such a revolutionary and versatile appliance, and how it can improve your hot water supply and your checkbook.

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How Does a Standard Tank Heater Work?

In order to understand the functioning of a tankless water heater, it’s helpful to know how a tank heater works also. In a standard tank system, water is kept in a state of perpetual heating. By maintaining temperature, hot water will always be available, even if it’s not the most energy efficient way of providing water.

Standard tank heating systems were the norm for U.S. consumers until recently when manufacturers realized that there was a more environmental way of heating water, and consumers realized there was a cheaper way to access hot water month-to-month.

How Does a Tankless Water Heater Work?

Tankless systems heat water in a completely different way that doesn’t cause as much standby heat loss, which is by providing hot water as needed. The water heats when it needs to, but doesn’t keep the heat stored unnecessarily.

You might be asking yourself how the water is provided so quickly if the water in the tank is not already hot. There is a part of the tankless heater, called a heat exchanger, that raises the temperature quickly and powerfully when necessary.

Heat is transferred from one device to another to quickly heat the water. Heat exchangers are also used in many household appliances like your refrigerator.

When the water needs to be heated, the incoming flow will signal the heat exchanger and quickly heat the water. This way, you’re none the wiser that the water stored in the tank is not always warm, and most importantly, you won’t have to wait for the water to heat up, which will save time, water, and energy.

What Kind of Tankless Heaters Are There?

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There are two types of tankless water heaters on the market: point-of-use heaters and whole-house heaters. These might sound self-explanatory, but to explain, they are two very different systems of water heating, with differing functionalities.

Point-of-Use Heaters:

Point-of-use heaters are small and compact and are better to be stationed in a closet or a cupboard. They are used for only one or two points that generate hot water, like your kitchen sink.

They are also electric as opposed to powered by natural gas or propane. They can also be used for smaller areas necessary to heat water, like an outdoor shower.

The positive aspects of the point-of-use heater include less water waste because it won’t take as long to heat the water, and the ability to be stored close to the water source. These systems are not ideal for bigger homes, where there will be more water usage.

However, for small households or apartments, point-of-use heaters can be a convenient and energy efficient way to heat water.

Whole-House Heaters:

If you live in a spacious home and have a significant budget, a whole-house tankless water heater is likely the route to take if you want to have instant access to hot water.

Because whole-house heaters are larger, they can provide heated water to multiple outlets in a house without having to work too hard, and can heat water at different points in the home simultaneously.

They are usually powered by natural gas or propane. This means that they have more powerful capabilities than the electric point-of-use heaters.

Calculating Your Flow Rate and Temperature Needs:

Before deciding on a tankless water heater and which one would be suitable for your household, it’s best to know how they will function based on your water needs and your flow rate, which is the total amount of water you will need heated at one time.

You will also need to calculate the temperature rise, which is the difference in the groundwater temperature of your water and the desired temperature.

These calculations will need to be based on various factors like what temperature you generally want your shower or sink water to be, and how much of it will be needed. These preferences will then need to be added to the capabilities and age of the mechanisms that expel the water, generally: the shower, bathroom and kitchen sinks.

The most important calculation to make when deciding on which heater is necessary is based on how many water fixtures will be running at once as tankless water heaters do not have an endless supply of hot water.

To Go Tankless or Not to Go Tankless:

The best tankless heaters, as well as the decision to go tankless at all is up to the individual and their water needs. They are not for everyone, but they can provide longevity, quality, and savings over time.

Because there are different ways of using them , i.e. the point-of-use or the whole-house models, going tankless can be easier than you think, and catered to your desires and needs.

It goes without saying that tankless water heaters waste less water and less energy, and that can be worth more than a price tag. No matter the cause, environment, budget, or personal preference, it’s worth knowing how your water system works.

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About Jennifer Hansen
Jennifer Hansen
Jennifer is a mother of 2 and has always been a careful shopper, determined to make the best buying decisions for her family. She loves researching the marketplace to find the right products for her household. She leads a small but mighty team of writers in bringing you WaterFilterSpot.
Jennifer Hansen
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