A tankless water heater is a more energy efficient option to a traditional storage tank water heater.

It is also known as an “on-demand,” “instantaneous,” “instant,” or “waterless” water heater.

A tankless water heater may provide all of your home’s hot water heater demands, from taps and showers to soaking tubs, dishwashers, laundry, and more, mounted on the wall in your garage, utility room, or outdoors.

With a tankless water heater, you may have hot water whenever you need it, wherever you need it, for as long you need it, provided you install a unit that is the right size.

In actuality, these are the two biggest advantages of tankless water heaters: 1) You won’t have to spend energy constantly keeping a lot of water hot, and 2) You can produce an endless supply of hot water, so you won’t have to worry about running out in the middle of a lengthy shower or trying to fill a bathtub to the brim.

What Is The Model Of A Tankless Water Heater?

Tankless units come in three different varieties at the moment: non-condensing, condensing, and hybrid condensing.

The fundamental idea behind all three is the same, even if they each work in a little bit different ways.

A heat exchanger coil transfers heat to incoming cold water flowing through the coil when a tap is opened, producing hot water for your faucet.

A gas burner ignites when the tap is opened.

(Electric tankless heaters that utilize elements rather than a gas burner are also available, although they are less efficient for use throughout the house.)

The devices consume a large amount of gas—typically between 150,000 and 200,000 BTUs—to heat the water to an appropriate temperature, which in most houses necessitates upgrading a gas line.

By adding a second heat exchanger to make use of extra exhaust heat, a condensing tankless water heater goes one step further.

Your water will be further heated, boosting efficiency while lowering running costs.

For “short draws,” or hot water demands that don’t utilize a lot of hot water, such hand washing, a hybrid tankless water heater has a tiny reservoir of 2 or more gallons.

Its total efficiency is increased by keeping this little reservoir full of hot water, which avoids the need for the appliance to completely fire up.

It is important to remember that tankless units do not really produce “instant hot water” since hot water must still travel from the unit to the tap.

Why Select A Water Heater Without A Tank?

Unlimited Hot Water

If you already possess a normal tank water heater and are wanting to replace it because it is outdated, ineffective, or leaking, a tankless water heater is an excellent option.

Others move to tankless systems because they wish to consume unlimited hot water or just cut their yearly water heating costs.

Tankless water heaters have been used for more than 20 years in Europe and Asia, but they have just recently been more widely accepted and used in the United States.

Less Energy-Intensive

A tankless water heater can save you space in your garage or utility room, last 20 to 30 years because it is less likely to rust and leak, increase the value of your home when you sell it, and is 40 to 50% more efficient than today’s standard tanks.

These are just a few of the benefits of using a tankless water heater.

A tankless water heater excels in both of these areas, whether your main priority is reducing your water heating costs or the environment.

For installing a tankless water heater, some utility providers even provide incentives.

Superior/Longer-Lasting Goods

The new federal laws governing water heaters that came into effect in 2015 are another crucial aspect to take into account.

From 2015 on, you will need to install a water heater with a minimum 82% efficiency if you currently have a gas water heater that holds more than 55 gallons of water.

Only tankless water heaters and the more uncommon, less thoroughly tested condensing tank water heaters will have this rating.

What Are Some Tankless Heater Benefits And Disadvantages?

#1. Advantages

  • Endless hot water: Because a tankless unit heats on demand, hot water will never run out. This is particularly helpful for houses with big families or homes with greater hot water needs — for instance, homes with a soaking tub or spa system are frequently suitable candidates for a tankless system. This is because tankless systems heat water on demand rather than storing it in a tank. We highly suggest that you give some serious thought to installing a tankless water heater in your home if you are replacing a bigger tank or contemplating increasing the capacity of your current tank from 40 or 50 gallons to 66 or 80 gallons.
  • Saves space: Tankless water heaters have a significantly reduced footprint, which enables homeowners to reclaim otherwise wasted space in their homes or garages.
  • Efficient use of energy: The standard gas tanks that are presently on the market work at an efficiency of 62-67%, whereas tankless water heaters operate at an efficiency of 82-96%.
  • Longer lasting: Tankless water heaters often come with longer warranties, and they may last up to twice as long as conventional water tanks. Because of this, you will need to repair your tankless unit just one-half as frequently as you would normally need to replace your tank.
  • Property resale value: In certain situations, homeowners may be able to recoup the cost of a tankless installation by increasing the selling value of their home.

#2. Disadvantages

  • Cost of retrofitting: The good news is that your subsequent tankless installation will entail none of these retrofit charges, which will result in a large reduction in the expense involved.
  • Longer wait time at the faucet: Many homeowners believe that installing a tankless water heater would reduce the amount of time it takes for water to heat up at a faucet. This is not accurate; in most circumstances, a tankless water heater would need around 15 more seconds to get hot water to the faucet than a conventional water heater would.
  • Lower running expenses are not guaranteed: Some homes may consume a lot more hot water on a regular basis since they can access limitless hot water. Because of this higher use, the savings on power expenses that resulted from the installation of an efficient tankless water heater may be nullified.
  • Tankless units need electricity: Because tankless water heaters require electricity, they are unable to supply hot water in the event that the power is interrupted.

#3. A Tankless Water Heater Choice

What is flow rate, and what questions should I be asking?

Tankless water heaters are compared using their per minute flow rate, as opposed to typical hot water tanks, which are evaluated using their gallon capacity, recovery rate, and first hour rating.

Most major brands’ typical flow rates fall between 4 and 12 gallons per minute (GPM).

Take into account these typical hot water demands and the necessary flow rates for each:

Dishwasher 0.5 – 1.0 GPM
Bathroom sink 0.5 – 1.5 GPM
Kitchen sink 1.5 – 2.0 GPM
Utility sink 1.5 – 2.0 GPM
Washing Machine 2.0 – 2.5 GPM
Shower 1.5 – 2.5 GPM
Bath tub 2.5 – .0 GPM
Jacuzzi/Hot tub 4.0 – 5.0 GPM

To establish the maximum flow rate necessary, take into account how many of these demands you could have at once.

We advise 6-7 GPM for a house with a single bathroom, 8–9 GPM for a house with two bathrooms, and 9–11 GPM for a house with three or more bathrooms.

Our experience has shown that smaller 4-5 GPM units work well for studio flats, small residences with one bathroom, and other application-specific requirements.

There are more alternatives, like as connecting many tankless units in series, for extremely big houses.

What is temperature increase, and how does it affect the maximum GPM I choose?

Depending on where you reside, the temperature of the water entering your house varies.

The typical winter water temperature for residents in the northern United States is 40–50 F.

The typical wintertime water temperature for residents of the southern United States is between 50 and 65 °F.

Where should my tankless water heater be placed?

When switching to a tankless water heater, many homeowners choose to move it.

Because there are indoor and outdoor units available, think about where you want to place your water heater.

Installation costs are often lower for outdoor installations.

What qualities ought to an Efficiency Factor (EF) have?

The tankless water heater will be less expensive to run the higher the EF.

Heat transmission from the energy source to your hot water is measured in efficiency.

The most effective tankless water heaters have an EF of.92 to.96, or 92-96% efficiency.

Which brand ought I choose?

When picking the brand of your tankless water heater, dependability, accessibility to local service providers, and warranty are crucial factors to take into account.

If your water heater requires servicing, be sure there are installers in your region who are authorized to work on the equipment.

How To Install And Care For A Tankless Water Heater

The two most crucial factors to take into account when selecting a tankless water heater are:

#1. Fuel Type

You may install a gas tankless water heater if you presently have a gas tank water heater (natural gas or propane).

The gas connection from your meter to your heater will likely need to be upgraded, however, since tankless heaters often need a dedicated line to handle their high needs of up to 200,000 BTU.

If you already use an electric water heater, you will need to connect an existing gas connection to your water heater setup or apply for gas or propane service to your house.

Switching to gas tankless is a terrific option and a great chance to take advantage of these rebates, which some utility providers give as considerable refunds for doing so.

For the majority of whole-home water heating requirements, we do not advise using electric tankless water heaters due to their subpar feedback, unfavorable temperature, and inadequate flow capacities.

#2. Location

It’s crucial to choose the ideal location for your tankless water heater to save space and have the lowest installation expenses.

Discuss with your installer the ideal location for a tankless water heater in your house.

Also take into account the fact that the device will need dedicated electricity.

Remember that the device won’t deliver hot water if the power goes off.

However, if you wish, installers may build a battery backup system.

Before starting work in your house, your installer should discuss the current plumbing rules and permit charges with you in order to estimate the overall cost of installing a tankless water heater.

Make sure you comprehend the criteria to ensure a secure installation of your water heater.

Additionally, ask your installation to explain how to maintain a tankless water heater on a regular basis.

Despite the minimal cost of maintenance, certain manufacturers do advise descaling, the frequency of which will depend on the caliber of the water in your area.

Your tank’s lifespan will be increased as a result of this.

The owner’s handbook in your vehicle might provide you with further advice.

What Rebate Options Are Available For Water Heaters Without Tanks?

For assistance in lowering the initial cost of buying and installing a tankless water heater, certain utility providers provide incentives.

To learn about incentives offered in your community, contact your utility provider or check out our page on rebates and incentives.

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Written by Bob Matsuoka
Bob Matsuoka is a blogger and founder of RVing Beginner blog. He has been blogging for over five years, writing about his own family’s RV adventures, tips for people who are interested in buying an RV or taking their family on an adventure by RV.