What are dielectric couplings?

What are dielectric couplings?

A dielectric fitting is a type of industrial material that isolates monitoring instruments against the effects of electrical current. One of its main purposes is to connect two types of pipe, such as iron and copper. Dielectric fittings disrupt the flow of cathodic current while allowing the fluid to flow.

Why do you need a dielectric union?

Dielectric unions are used to separate two dissimilar metal pipes (such as copper pipes and galvanized steel). Purpose of dielectric unions is to prevent galvanic corrosion, which is caused by electrolysis.

How do I install dielectric?

First step: Wrap several layers of pipe sealing tape over the threads of the steel pipe. Install the threaded end of dielectric union body to the steel pipe. Turn the union clockwise and tighten with a pipe wrench. Second step: Slide the union nut over the end of copper pipe with open threaded end facing out.

Do dielectric unions leak?

A dielectric union is a plumbing fitting that is meant to join two dissimilar metal pipes so they don’t experience a galvanic reaction and begin to rust. We find many dielectric unions that have started to rust which will eventually lead to a water leak if not remedied.

What is a dielectric fitting made of?

Dielectric unions are use to join pipes made from dissimilar metals to avoid electrolysis which leads to corrosion and pipe failure. This union is made from galvanized steel and lead-free brass. Plumbing codes in all states require the use of dielectric unions when connecting dissimilar metals.

Do you tape dielectric unions?

Dielectric unions are COMPLETELY worthless. Teflon tape is intended to “disappear” when the joint is made and just fill any voids in the thread. The actual threads are in metal to metal contact so electrolysis can still occur.

Why do dielectric unions fail?

every single union fails miserably by either leaking, clogging up completely, rusting to pieces with no water contact outside pipe or depositing rust in water.

Do new water heaters need dielectric unions?

Dielectric Unions If either the tank nipples or the pipes are galvanized steel, however, and you are connecting them to copper, you must use a fitting called a dielectric union to make the connection. Both the hot and cold water pipes must have this fitting — it’s a code requirement.