Help replacing old Atwood Water Heater with New Atwood

Due to closed system and higher normal temp t-stats weeping can occur when air gap is not present.

Air gap allows for swelling of water when heated and absorbs increase in pressure

Turn off water supply
Open faucet hotside to relieve pressure
Open T&P Relief Valve with lever,,,,,,,,,,when water stops flowing out let it snap closed
Turn on water supply close faucet