- 1). Consult the most recent home inspection report to determine the metal of your plumbing pipes. Typically, they will be copper or galvanized steel, though other types may appear in older homes or different geographic areas.
- 2). Look at the pipes under the sink, if a home inspection report is not available. Copper pipes will have a reddish-orange or brown appearance. Steel pipes will be gray. Some pipes may still retain the manufactures labeling.
- 3). Purchase a faucet with tailpieces composed of the same metal as your plumbing. The box the faucet comes in or the accompany literature should tell you the exact metal comprising your faucet. If you are not sure, ask a sales representative or purchase a faucet that does supply this information.
- 4). Purchase a dielectric union, if you are not able to purchase a faucet with the same metal as your faucet. The dielectric union will prevent the transfer of electric current between the two metals and keep the faucet from corroding.
- 5). Contact a plumber to install the dielectric union. The union consists of a copper piece of pipe separated from a steel coupling by a rubber gasket. The installation of a dielectric union is labor intensive and requires expertise to install properly, ensuring prevention of electrolytic conversion.
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