Copper and galvanized steel pipes pipes do not mix. When you join them in such a way that they are touching each other, they develop a tiny electric charge that corrodes the combined, and the result would be a leaking water line. So as to protect against this, plumbers join copper pipes into galvanized steel ones using dielectric unions, which are fittings using nonmetallic washers that maintain the pipes split. You need to use dielectric unions to join an electric water heater into a method of copper pipes if the heater includes preinstalled galvanized nipples.
Separate a 3/4-inch dielectric marriage into its part halves by unscrewing the central nut. 1 half is constructed of galvanized steel and has female threads; another half is copper or brass and contains a slip joint. Between the halves is just a plastic or rubber washer.
Wrap pipes tape around the threads of this cold-water the hot-water socket nipple attached to the top of your electrical water heater. The cold-water inlet is usually identified by a blue sticker on the surface of the heater; the hot socket by a red sticker. Screw about the galvanized half of this dielectric marriage and tighten it, using a rhythm.
Slide the marriage nut on the 3/4-inch copper pipe that you’re going to connect to the heater using its threads facing the end of the pipe. Spread soldering flux on the exterior of the pipe and also on the inside of the brass half of this marriage, using the brush that’s supplied using the flux. Slip the marriage on the pipe. Solder the marriage on the copper pipe, using lead-free a propane torch.
Bring the copper and galvanized pipes together following the matching has cooled. Insert the washer between them and screw the marriage nut into the threads on the galvanized half of this fitting. Tighten the nut using a pipe wrench or a large pair of adjustable pliers.
Combine another water heater vent into the water heater at the same way.