How To Install A Tankless Hot Water Heater

Gary Johnson
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Installation Costs

Installing a tankless water heater is an investment. That is why it’s important to ensure you are saving money with each hot water cycle. The two most important items in this department are the efficiency and installation costs.

Tankless water heaters are more efficient than tank water heaters. They use about 2,000 BTU to heat 1 gallon of water, whereas tank water heaters use 3,000 to 4,000 BTU to raise the temperature a gallon of water.

In addition, the heater has a rated efficiency of 80%, which means that 80% of the energy that goes in comes out as hot water. All of these benefits add up to significant cost savings.

You can save a lot of money on utility bills because tankless water heaters use much less energy than tank heaters. The natural gas or propane gas that runs through the tankless heater needs a way to be vented outside of the house. In order to complete this process, you should hire a professional to do the installation.

In addition to the installation costs, there are other factors to be considered, such as maintenance requirements, replacement costs, additional taxes and government fees, and more.

While the initial investment on a tankless water heater is a bit more expensive, you will save money by using less energy and less natural gas or propane.

Installation Considerations

The tankless water heaters can be installed by anyone, however, you need to follow some standard rules incorporated in its proper installation. Installation may require some wiring and other considerations. If your water heater is more than 10-years-old, it might be time to replace it with a new tankless water heater according to the energy Star scale.

There are some things you must check before purchasing and installing a tankless water heater. First, decide clearly if the installation of tankless heater is also going to need electrical wiring changes or not. If it is possible avoid doing electrical wiring check with all, if you’re not sure about this.

Check the quantities of water outlets and the existing plumbing in your place before deciding to install a tankless water heater. You should consult an expert plumber to figure out the best way to install a tankless water heater in your home.

The installation of a tankless water heater will take a few hours normally and you won’t face any major problems as long as you’re careful. It is better to consider hiring an expert plumber to do the job otherwise there might be some leaks, if you skip the process of hiring an expert plumber.

Installation Safety Guidelines

Make certain you've turned the power off to the water supply before you begin working. Electrical shock is the least of your worries since water and electricity are never a good combination.You want to make sure the water is turned off at the main control valve. This valve is not always easily located. In some cases, it is under the sink, but in most cases, it is in the basement.

Make certain you know where the shut off valve is at no matter how long you have lived in your home. Locate and mark it now. This will minimize a lot of problems if you have a plumbing problem sometime in the future.

Make certain looking under the sink will not void your plumbing repair warranty. Some sink manufacturers will void the warranty if you cut the plastic cloth from the back of the sink cabinet. The warranty may also be void if there was a previous leak.

You might want to realize that these plumbing repairs take time and can be a money drain. Contractors expect to be paid after the job is completed. Their time on the job when a leak is found or when a new plumbing system is installed should be considered an investment in your home.

In some cases, this means you pay upfront for the plumbing repair and then the contractor will submit the bill to your insurance. This should be left to the insurance and you should not have to pay in advance nor do you want your money tied up in the big plumbing contract.

Steps on How to Install a Tankless Hot Water Heater

  • Evaluate your needs.
  • Research the best type of tankless water heater for your needs. Tankless heaters come in natural gas, propane, and electric. They also come in gas, solar hybrid, and gas plus electric hybrid.
  • Figure out the best places to install and purchase the system.
  • Attend the class for the type of water heater you choose.
  • Plan for the clearances needed for the installation.
  • Get the permit.
  • Afford the equipment installation.
  • Be sure there is a source of electricity for the heater.
  • Seal the cold heating elements with T-8 threads and unions.
  • Take the needed extra precaution when working with natural gas.
  • Run the copper tubing in the wall.
  • Attach the copper tubing to the manifold.
  • Install the pilot light.
  • Lay the hot water pipe.
  • Install the gas line.
  • Install the gas line connection.
  • Attach the water line from the heater to the water heater.
  • Install the heating element.
  • Install the insulation to the water heater.
  • Install the drain thermostat.
  • Hook up the gas supply.
  • Verify that everything works properly.

Hot Water Maintenance

It takes a lot of effort and money to get hot water to your home. The more consistent and efficient your hot water system, the better your plumbing will run and the longer it will last. The following tips are some of the best ways you can maintain your hot water heater to reduce water temperature loss, repair costs, and future upgrades.

Keep It Clean, Regularly

Most hot water heaters have corrosion. If you don’t give it a regular cleaning, that corrosion can build-up and eventually cause short circuits.

My favorite way to clean the tank is to lug it out from its hard-to-reach location, then pour about a half gallon of vinegar into it. I use a scrub brush or dish soap on a rag to scrub all sides of it.

Next, I take a hose and spray it out from the inside and out, checking to make sure the holes are free and clear of anything.

Finally, I pour just a little bit of bleach into the tank, let it sit for an hour or two, and then rinse it out with a hose and hot water pump.

Use A Water Heater Protector


Tankless hot water heaters are really useful appliances to have. Tankless water heaters are normally indoor appliances that don’t use hoses, require no more space than small appliances like a dish washer and can be installed by anybody.

The small size and fact that they produce hot water on demand makes them great for dorms, apartments and condos where space is an issue. These units are perfect for both residential and commercial applications.

It is important to know what you want from your tankless water heater. If you need hot water instantly, then you will need a unit that is capable of producing hot water on demand. Many types of water heaters can turn on but take a few minutes to get hot water.

If this doesn’t work well for your needs, consider a tankless water heater that produces a continuous flow of hot water. If you want hot water, then you should be able to turn on a bathroom or kitchen faucet and get hot water.

A few people want backup hot water, but at the risk of losing hot water if there is a break in the water line. If you don’t want backup water, then you may be able to get skip heating altogether.