When To Use Dielectric Union? Tips for DIY Plumbers

Dielectric unions are responsible for the prevention of accelerated corrosion and deterioration in the piping system. It is normal for minerals deposition to occur with piping system, and that can occur as a result of hard water but leaving it will only lead to corrosion and rust, which can lead to leaking.

The best way to prevent corrosion from happening very fast is through the use of dielectric union. The use of dielectric union is common in commercial and residential applications, and it helps to do great work to ensure the piping system remains in proper condition for a longer period.

In a most piping systems, plumbing codes require the use of a dielectric plumbing fittings whenever you are joining steel piping to copper or some other metals.


When Are Dielectric Fittings Required ?


You need to know the right time [ when to use a dielectric union ] for you to make use of dielectric, and if you do not, below are some right situations for you to make use of dielectric fitting.

If you are working with galvanized steel pipe, tank nipples and you have to connect them to copper, and it is important that you use a dielectric union to make the connection. The hot and cold-water pipes must have this dielectric union fitting for proper operation.

Not all stainless steel can work well with brass, and it takes a professional plumber to get their way with such plumbing work. Using the wrong fitting will lead to corrosion which is the reason the use of dielectric union is the best option.


Dielectric Union Purpose


Just in case you are still confused about the use or the operation of a dielectric union, you should understand better from this information. Copper dielectric union is a special fitting that is good for the connection of dissimilar metals.

If you are connecting a copper wire to a galvanized iron pipe, using a dielectric union to hold the two metals together is the right thing to do.

The reason for using dielectric union is that dissimilar metals get to corrode whenever they come in contact with each other. Little quantity of acid in water can trigger electrolyte reaction, which then later leads to corrosion and rust for the pipes.

While the dielectric union is important to prolong corrosion time, the elastomeric rubber gasket seals the connection to prevent any tube connection to tighten the nut on the dielectric union. You should choose the right union fitting as there are many such as 1” dielectric union, sharkbite dielectric union, and threaded dielectric union, to mention a few.


Dielectric union copper to galvanized

It is not appropriate for you to connect galvanized pipes to copper pipes directly. The only successful way you can do that or replace a galvanized pipe with a copper pipe is with the use of plumbing dielectric union.

The primary reason for this is to prevent corrosion in the long run. If you are one of those that ask the question about do i need a dielectric union for brass to galvanized? Yes you do. Brass is known to be an alloy of copper and nickel.

The effectiveness might be unknown to you. But for any plumbing work to be perfect which has to do with joining metal pipes together, you need dielectric union.


Are Unions Necessary ?

Without a doubt, they are essential and indispensable whenever you are doing any plumbing work that requires joining two metals together. Using dielectric union galvanized to copper is never a bad idea to prevent corrosion if you are using the copper with any other metal.


Do new water heaters need dielectric unions ?

Using a dielectric union for new water heater depends on the kind of connection you have with the piping system. If the tank nipples or the pipes you are using are galvanized steel and you have to connect them to a copper pipe, you sure need a watts dielectric union to make the connection.

Both the cold and hot water pipes must have this fitting as it is the necessary requirement to achieve proper plumbing work.


Dielectric Union Installation


If you are doing the installation yourself without the assistance or help of an expert, you need to follow the step I’m about to share with you below.

First step

You should wrap several layers of the pipe sealing tape over the threads of the steel pipe and go on with installing the end of the threaded electric union body to the steel pipe. Now, you should turn the union clockwise to tighten. All can be done using a quality wrench.

Step two

Slide the union nut over the end of the copper pipe while you ensure the open threaded end is facing out. Pick the orange color plastic insulator and pass it over the copper pipe.

Step three

Now you can go on with installing the copper solder adapter onto the copper pipe and join the solder to the copper pipe using a propane torch. Ensure you place the plastic insulator as far away from the torch to avoid it melting the insulator. Then allow the pipe to cool.

Fourth step

Slide the rubber gasket between the union nut and the union body and then assemble them together. Turn the nut clockwise and check to ensure there is a tightness so that no water escapes.

Final Words

If you have piping work to do and you are confused or curious about When to use dielectric union, we have given you the right information on this page to help you with such a task. We hope you have a successful operation with the dielectric union.