The expansion tank connects onto the cold water supply line near above your water heater. You can install an expansion tank using push fit fittings. They slide onto the pipe, no soldering needed. If you decide to solder, de burr and clean pipes and fittings. Apply soldering paste andemble. Heat the fitting and solder..Install a new gas water heater in your home and save energy and money. When installing your water heater, make sure to follow specific information, warnings, safety notices and local codes. These instructions aren’t intended for mobile home units. Consult a professional if in doubt..Let the water heater tank fill with water turn on a water faucet in a remote bathroom or the kitchen when water comes out of the faucet, the tank is filled the water will be cold . Restore power to the water heater circuit, for an electric heater..The Rheem product range extends to gas water heaters, If you’re installing a new water heater or replacing Our water heater installation pricing .