Threaded Dielectric Union Options at EPCO
We offer dielectric unions in several connection styles to fit a wide range of
industrial sectors and applications. All models feature zinc-coated cast steel and brass construction for corrosion resistance.
Style Options
- Female Iron Pipe (FIP) - Sweat (SWT): Threaded female fitting with a soldered copper end
- Male Iron Pipe (MIP) - Sweat (SWT): Male threaded pipe end with a soldered copper end
Size Range
When Are Dielectric Unions Required?
Dielectric unions are required when dissimilar metals are joined in a piping system, like copper and steel. Without them, galvanic corrosion can occur at the connection point, leading to leaks and system failures. These fittings are commonly used in hot water systems, HVAC piping, and other applications where steel pipe and copper tubing must be connected.
Dielectric Union FAQs
How do dielectric unions work?
A dielectric union uses a non-conductive barrier, often a plastic or rubber gasket, between two different metals. This barrier prevents electrical current from passing through the joint, which stops galvanic corrosion from forming at the connection.
Are dielectric unions required on water heaters?
Yes. When a water heater with steel connections is installed onto copper plumbing, a dielectric union is typically required by plumbing codes to prevent galvanic corrosion.
What metals need a dielectric union?
Dielectric unions are needed when copper is joined with galvanized steel, black steel, or iron pipe. These combinations are most prone to galvanic corrosion when installed without a protective barrier.
Why do dielectric unions fail?
Failure usually results from improper installation. Over-tightening, misalignment, or damaged insulating gaskets can compromise the non-conductive barrier, which reduces effectiveness and allows corrosion to occur.
How long does a dielectric union last?
With proper installation, a dielectric union can last decades. Service life often matches the life of the piping system, provided the union is correctly installed and maintained.
Contact Us to Learn How EPCO Can Be Your Source for Threaded Dielectric Unions
Contact us to learn how we can supply you with EPCO dielectric unions with fast order turnaround. Need other
hose and fitting products? We maintain an extensive in-stock selection of
pipe fitting valves,
tubing, and more. EPCO is your one-stop source for threaded dielectric unions and other industrial supplies.
