Whether installing an electric or gas unit, a water heater requires hot and cold water lines and a drain for the temperature and pressure relief valve. The plumbing for this project requires copper tubing, fittings, a torch and soldering supplies.
When installing a new water heater, turn off the water at the main shutoff location, and shutoff the gas or electricity to the area. If replacing an old water heater, drain the hot water from the faucet. Once the water runs cool, turn the water shutoff valve. Once the tank drains, disconnect the water lines and the electrical or gas connection.
To install a water heater, remove it from the box, and place it on a platform made of concrete blocks. If the new water heater is the same height as the old one, make the connections in the same manner as the old one. If the water lines need to be installed, locate the closest water supply line. With the water shut off, cut the copper water pipe, attach the appropriate fittings, and solder the connecting joints. Install a shutoff valve at the end of the cold water line and a union on the hot water pipe.
Water heaters have a safety device, the temperature and pressure relief valve, that opens to relieve pressure in the unit. In cold climates, it is recommended to let it discharge into a floor drain, but some localities require that it drains outside.