Turn off power to the water heater at the breaker or shut off gas supply at the gas valve
Turn off the cold water supply to the heater
Open a hot water faucet to relieve pressure
Drain the tank through the drain valve into an appropriate drain or hose
Disconnect the water supply lines
Disconnect the gas line or electrical wiring
Disconnect the venting if it is a gas water heater
Remove the old water heater
Place the new water heater in position
Level the new water heater
Connect the water supply lines
Connect the gas line or electrical wiring
Connect the venting if required
Open the cold water supply and fill the tank
Check for leaks at all connections
Purge air from the hot water lines by opening faucets
Restore power or relight the pilot according to the manufacturer instructions
Set the thermostat to the desired temperature
Verify proper operation of the water heater