Are dielectric unions necessary?
If all of your water piping and connections from the copper to other fixtures or devices are copper or brass (or plastic) you’re fine without adding dielectric unions. Use a dielectric fitting between copper an steel as described in this article, both to comply with plumbing codes and to avoid corrosion and leaks.
What does a dielectric union do?
Dielectric Unions are used in commercial and residential applications to prevent accelerated corrosion and deterioration in the piping system due to galvanic and stray current. It is installed between pipes made from dissimilar metal. We offer dielectric unions in a range of configurations, sizes, and materials.
Can you use a brass fitting instead of a dielectric union?
What is Brass Fitting? Brass fittings and nipples are also commonly used as a great alternative to dielectric unions for water distribution systems. When galvanized water is exposed to certain water qualities, rust is produced and to prevent that from corroding, brass fittings can be used.
What is dielectric union fitting?
A dielectric union is a special adapter or fitting utilized in the piping systems of various metals to isolate the connection of the dissimilar metals. For instance, when linking a copper pipeline to a galvanized iron pipe, a dielectric union is set up between the two to hold the two different metal pipelines together.
Do dielectric unions leak?
As you can see from the picture above, while these unions have a great intent to keep the water heater connection lines from rusting, that is not always the case. We find many dielectric unions that have started to rust which will eventually lead to a water leak if not remedied.
Is it OK to mix brass and galvanized fittings?
To safely connect copper and galvanized steel, you have two options. Since brass doesn’t react with either the copper or the zinc, one method is to make sure you have a threaded female end on both the copper and the steel pipes, and then connect the two by simply inserting a short threaded brass nipple between them.
Do you need a dielectric union between galvanized and brass?
Joints between copper or copper-alloy tubing and galvanized steel pipe shall be made with a brass ñtting or dielectric fitting or a dielectric union conforming to ASSE 1079.
Do you need a dielectric union between stainless and copper?
When connecting copper to carbon steel or galvanized steel, flanges or dielectric unions should be used to electrically insulate each material. When connecting copper to stainless steel, a brass or bronze fitting between the two metals provides sufficient electrical separation in most environments.
Why do dielectric unions fail?
Often the issue is that these fittings are not perfectly installed and some small contact is made. Additionally, if you use a union with a short sleeve, then that can be an issue as well. It is good to be able to visibly see the sleeve above the union nut at the end of the installation.
Do I need a dielectric union for brass to galvanized?
What causes pinholes in copper water pipes?
The primary cause of pinhole leaks is the composition of the water flowing through your plumbing system. Hard water—high amounts of dissolved calcium and magnesium—or water that is too basic (low pH) or too acidic (high pH), can all contribute to copper pipe corrosion.