An Electric Tankless Water Heater

How to Install an Electric Tankless Water Heater Yourself in 12 Steps

For those of you who have decided to go with an electric tankless water heater, kudos to you! You’re one step closer to paying less for your electricity bill and having hot water endless, on-demand.

Selecting an electric tankless unit is one thing; installing it is another, especially since you may have to hire licensed professional help.

If you’re the DIY-king and have the skills and the patience for installing an electric tankless water heater, you should keep reading to find out the tricks and tips for proper installation.

What are the requirements for your electric tankless water heater?

You cannot just go ahead and install an electric tankless water heater, especially since not all homes are ready to handle an entire house electric tankless water heater. The high amp draw of the system is the main reason for it.

  • The power requirements

For instance, some electric tankless water heaters need three different dedicated 50A double pole breakers, with at least 300A leading service. Just to give you an idea, keep in mind that an average home only has a capacity of 200A.

Therefore, you may have to upgrade the old electrical service panel with bigger wires and more significant breakers. Sometimes, you may even have to run an entirely new one, which adds a couple of thousands of dollars to the initial investment.

You can also find units that only need 2x50A double pole breakers and 150 leading services. In the case of point-of-use electric tankless water heaters, no worries about the amperage requirements. Even if most units need 240V power, some tiny POU units may run on 120V.

Should you seek help when identifying your home’s electrical service? Go outside your house and take a look at the electrical breaker box. A label in the electrical panel may come in handy, too, and your electrician may provide you the info.

  • Water pressure requirements

Most electric tankless water heaters need pressure going from 30 and 150psi. If the incoming water pressure is higher than 150psi, you have to install a reducing valve upstream of your heater.

  • The permits you need

If you’re the homeowner, there should be no problems installing the unit on your own. Nevertheless, most states require you to receive a permit for safety reasons. It’s a similar situation when you replace an old unit.

Expect a visit from the plumbing inspector as he/she has to check the installation, making sure that everything will work safe and smooth.

Where’s the ideal place in a house for the electric tankless water heater?

Even if electric tankless water heaters don’t take much place and are relatively easy to mount, you still need to think about where you’re going to fit the water heater. Should you install a whole-house unit, you should mount it close to the appliances using it the most. This way, you will have warm and hot water faster than you think.

Don’t forget that you also need access to the main cold water line. In the case of use systems, you should install them really close to the point of usage, so that the water gets to the outlet fast enough.

One of the best parts about the electric tankless water heaters is that they don’t need venting nor a tank to worry about. A small bathroom and under the sink are great places to install an electric tankless water heater.

Electric tankless water heaters require vertical installation, whereas the water and the power supply connections are downward oriented. You should have minor clearance for servicing.

You shouldn’t install the electric tankless water heater in places where freezing temperatures may appear. Don’t fix it in a place where it can be splashed with water or other liquids, either.

Should you not consider the mentions above, you may void the product warranty.

What tools and supplies are essential for installation?

If you’re a DIY-fan, you probably have all the tools you need for installing an electric tankless water heater.

Nevertheless, it’ better that you check our list of tools too:

  • Flathead screwdriver
  • Drill&drill bits
  • Needle nose pliers
  • Philips head screwdriver
  • Pipe cutter
  • Pencil
  • Adjustable wrench
  • Tapes measure

Here’s the list of supplies you should prepare for mounting the electric unit:

  • Shut-off valves
  • Mounting screws and anchors (they typically come with the heater
  • Pressure reducing valve
  • Teflon tape
  • Temperature and pressure relief valve (T&P)
  • Pipe insulation
  • Wire&ground
  • Double pole circuit breakers
  • Sandpaper
  • Recirculation pump&crows-over valve

At times, you may need some tools and supplies for welding or soldering.

What are the steps to take when installing an electric tankless water heater?

We should start by reminding you that the following steps are general, as each model may come with specific steps to take.

Improper installation may void the warranty, so stay safe by hiring a licensed electrician if you don’t have the skills for the job.

Here are the steps:

   1. start with turning off all involved circuit breakers

   2. Shut the primary water supply off

   3. Drain and cut the connection with the old water heater (when you have one)

   4. Put the screws securing the front cover of your unit. Remove the front cover and place it aside carefully

   5. Mount the unit to the wall. You should have all the screws and anchors you need in the package

   6. Set the cold and hot water connection. It’s going to be more comfortable when using stainless steel flex pipe (3/4″), along with Teflon tape. Copper or PEX tubing may also work, but they have to be made for high-temperature applications. Install a shut-off valve before and after the unit and a pressure reduction valve, if necessary. It’s not required, but it’s a good idea to also install a temperature and pressure relief on the hot waterside.

   7. Set the electrical connections with the water heater on one side, whereas the electric panel is on the other side. Look in the user manual for the proper wire and circuit breaker number and size

   8. Go over the electrical connections once again, making sure that you didn’t combine any wire sets the wrong way.

   9. Put the front cover back again

   10. Turn on the circuit breakers

   11. Turn on the water heater and set it according to your likings. Now it’s time to set the water temperature as high as you want.

   12. Open the hot water outlet, waiting for the temperature to stabilize. Go over the heat, adjusting it if necessary.

The final tip

Installing electric tankless water isn’t very difficult, especially if you have the skills for it. However, never do it without the user manual or when worrying about voiding the warranty.

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