Water heater serial number lookup
How old is my water heater? This water heater serial number lookup answers that from the serial on the rating label. On a tank water heater the rating label is on the side of the tank, usually above the gas valve or the lower element cover. On a tankless unit it is on the side or bottom of the cabinet.
Where do I find the serial number?
Look for the rating label on the side of the tank, usually near the gas valve or the lower access cover. On a tankless unit, check the side or bottom of the cabinet.