Giant water heaters carry the build date inside the serial number.
Giant does not put the date in the serial number. Look for the production date printed on the rating plate itself.
A standard tank water heater usually lasts 8 to 12 years. Some make it to 15 with soft water and a replaced anode rod; some fail at 7.
How long does a tank water heater last? · Should I replace my water heater? · DC Dept. of Energy & Environment, InterNACHI
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