What is a Tankless Hot Water Heater? -Benefits, Costs & More

What Is A Tankless Hot Water Heater - Benefits, Costs and More

Are you tired of your traditional water heater? You know the big round traditional tank in your garage or home? It not only takes up room but also makes quite a bit of noise, and what a mess if it starts to leak. Oh, and are you tired of waiting in line for a cold shower in the morning because there is no hot water left? What is the solution for this – A Tankless Hot Water Heater. What is a Tankless Hot Water Heater? – Its Benefits and More explores tankless water heaters and discover why one might be an excellent option for you. We will talk about the benefits, what to look for when purchasing one, installation, and maintenance.

What Is A Tankless Hot Water Heater

What Is A Tankless Hot Water Heater?

A Tankless Hot Water Heater is a water heating device that, when activated, provides a constant flow of hot water coming from the hot water tap. Tankless Water Heaters are also known as “instantaneous” or “on-demand” because they heat water only when you need it.

Heating Process

When you turn on a faucet, shower, or appliance like a washing machine, cold water is brought through a pipe into the tankless water heater. Water is heated as it flows through the heat exchanger. Then the water flows through the tank and into the faucet, shower, or appliance you turned on; this process happens very quickly. Again, no water is stored in tankless water heaters, unlike a conventional water heater that keeps hot water in the tank and is continuously being heated.

What Are The Benefits of a Tankless Hot Water Heater?

There are many benefits of having a tankless hot water heater:


The best thing about tankless hot water heaters is they only activate when there’s a need for more hot water. Because the water is heated as needed, it saves on energy and money on your utility bills. Also, by heating water only when needed, tankless water heaters do not experience standby heat loss. Standby heat loss occurs in tank heaters when heat escapes and the water needs constant reheating.

Tankless water heaters use about a third less energy than a tank-style heater to heat the equivalent amount of water for showers, dishwashing, or other tasks. Being they don’t waste as much energy heating water that isn’t being used, this feature is perfect in colder climates where energy costs are already high.

Tankless hot water heaters can also be an excellent choice for smaller households because tankless models use only approximately 30 – 170 kWh per month, depending on the number of occupants and how much hot water is used. In comparison, storage tank water heaters use up to 300 kWh per month. You can save more money on your monthly utility bills with tankless models, especially if you have low hot water usage in your household.

Constant Supply

What Is A Tankless Hot Water Heater? Its Benefits and More - Shower

Another benefit that makes tankless water heaters a good choice is that if you live in a larger home or one with multiple people using hot water at once, you won’t have to worry about not having enough hot water for all the demand. A storage-type heater can only hold so much, and when it runs out, you will have to wait until it heats up again, which can take anywhere between 30 minutes and an hour.


The compact size also makes installation much easier than conventional water heaters. There is no need to worry about running pipes from the heating unit to the location of the needs. Almost any area can be used with a tankless model because it doesn’t have to be mounted to a permanent wall or structure. For instance, it can be mounted on a cabinet next to your kitchen sink or a wall inside the garage.


Tankless water heaters don’t burst. There is no tank, so there’s no need to worry about pressure buildup. Some tankless water heaters are natural gas-powered, so there is technically a risk of a carbon monoxide leak, but this can usually be avoided as long as you schedule regular maintenance.

Because tankless water heaters don’t store either cold water or hot water, the risk of flooding is tremendously reduced (although damaged pipes still pose a potential threat).

Life Expectancy

While traditional storage heaters can last anywhere from 8-15 years, tankless water heaters, when installed properly and maintained, generally last 15-20 years due to their simple design and lack of moving parts.

Less Noise

Generally, tankless hot water heaters are much quieter when they heat water than their counterpart. A traditional system will make loud banging sounds as the water is heated. Even though tankless water heaters will still make some noise with the water rushing through the unit, it won’t be as loud as one with a tank involved. The noise of a tankless hot water heater has been compared to the noise an electric can opener or a computer fan makes.

As you can see, tankless hot water heaters have many benefits, such as saving space, money, and energy. They also help the environment by reducing your carbon footprint, which can be an advantage or disadvantage depending on how you look at it.

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What Are The Cons of A Tankless Hot Water Heater?

Though tankless hot water heaters have many benefits, they also have some cons.

  1. Generally speaking, a tankless unit’s upfront cost and installation are more expensive than a tank model.

2. A tankless heater may have inconsistent water temperature when multiple outlets are in use.

3. It can be challenging to achieve a lukewarm temperature with a tankless water heater.

4. There is a risk of having no access to hot water during a power outage with a tankless heater.

What To Look For When Shopping For A Tankless Hot Water Heater

When it comes to tankless hot water heaters, there are many options out on the market. A few features you should consider in a tankless water heater are:

Type of Fuel

Knowing if you need an electric, gas, or propane model.

Generally speaking, natural gas tankless water heaters have been more energy efficient than their traditional counterparts, but the efficiency usually only lasts for a while before it starts declining. There are electric models with 98+% efficiencies, which means they’re more cost effective, last longer, and don’t require as much maintenance. In addition, gas prices change drastically from month to month, making them unpredictable, whereas electricity costs vary less often, so its value remains constant even when the fuel marketplace is unstable

Energy Factor Rating

An important feature is a tankless model that comes with a high energy factor rating. The more energy efficient a tank is, the better.

Vented vs Ventless

You may want to look for a model that doesn’t require a vent since that can save you some installation costs.


With any major purchase, you want to inquire about the warranty. What does the warranty cover and not cover? How long is the warranty good for? What can invalidate the warranty? It’s always good to know upfront what will be required to make a claim on the warranty. Also, if there is a place to register the tank with the manufacturer, be sure to do so.

Gallons Per Minute

You want to determine how many gallons per minute (GPM) you will require. Generally speaking, the higher GPM you get, the more expensive it will be.

The table below posted by Learnmetrics.com shows the recommended size of tankless water heater for the number of people in the household. As they state, These figures are for reference only. Several important factors like inflow water temperature and acute hot water needs determine the exact size of the tankless water heater you need.

Number Of Family Members:Gas Tankless Heater Size (GPM)Electric Tankless Heater Size (kW)
What size tankless water heater do I need for a family of 2?6-8 GPM10-18 kW
What size tankless water heater do I need for a family of 3?7-9 GPM15-23 kW
What size tankless water heater do I need for a family of 4?8-10 GPM20-28 kW
What size tankless water heater do I need for a family of 5?9-11 GPM25-34 kW
What size tankless water heater do I need for a family of 6?11+ GPM34+ kW

Multiple Tanks

If you have a large home or one that has many occupants, an option you might want to look at is installing multiple tanks. This will ensure that enough hot water will be available for all the showers, appliances, and taps.


The installation process is relatively easy for tankless hot water heaters. However, installing a tankless heater is not a job for inexperienced do-it-yourselfers. It’s always best to call a professional who has experience installing either a gas tankless water heater or an electric tankless water heater.

The typical cost of installation varies from place to place. And although installation costs may be higher with a tankless system, over time, a tankless heater may save you more money than a traditional water heater.

What To Look For In An Installer

When looking for a contractor to install your water heater, there are a few things you should do:

  • Be sure they have a license.
  • Request a quote in writing. This way, there shouldn’t be any discrepancy with the cost. If there are additional charges, they should be agreed upon before any work is done.
  • Be sure they will be responsible for pulling any needed permits.
  • Ask for references so you can call and see if the job was done to the customer’s liking. However, do be aware that the references you are given will probably not include dissatisfied customers.
  • Check with the Better Business Bureau to see if there have been any disputes with the contractor and if they were resolved.

What Kind of Maintenance Does a Tankless Hot Water Heater Require?

Tankless water heaters require little maintenance. One part of maintenance is descaling the water heater, and this is done by removing limescale and other mineral deposits from the burner system inside the tankless water heater. If you have hard water or your family uses a lot of hot water, you can expect to do this once a year.

With proper maintenance and operation, tankless water heaters can last anywhere from 15 to 20 years. In comparison, a standard tank water heater typically has a working life of 10 years or less.


In What is a Tankless Hot Water Heater? – Its Benefits and More we found a tankless hot water heater is an excellent option for homeowners who want to save money and reduce their carbon footprint. They take up less space than traditional heaters, so they can be installed in places where tanks won’t fit. Plus, there’s no need to worry about running out of hot water with these systems. And don’t forget that installation and maintenance are just as important as choosing the right system – without proper care and attention from an experienced technician, it could cost you time and money down the line.

What is your experience with water heaters? Please comment below.

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