Shut off water at the main entry of the house or the water heater or the water meter. Turn off the gas supply at the water heater. Cut inlet Cold and outlet Hot on the top of the water heater. Disconnect vent line, remove T&P line, and drain down old water heater and remove. Set and install per code new heater in place and level, install appropriately sized aluminum drain pan and connect as necessary, reconnect to existing piping using lead free fittings within 5ft of existing pipe, new gas whip, new 1/4 turn gas shutoff, thermal expansion tank, vent line modification with in 3ft, install full port lead free ball valve, add or replace thermal expansion tank and pressurize pressure to match regulated pressure entering home, note psi on tank as well as install date, pressurize system, test and clean up work area, register warranty, take away old unit.( Pressure reducing valve must be working correctly to validate any warranty ). Rheem Pro-G40. Thank you for choosing te certified