U.S. Craftmaster water heaters carry the build date inside the serial number. We know one serial format for this brand; the decoder tries each one and shows every reading that fits.
The first two digits are the year and the next two are the week of that year. An S in front is a factory code and is ignored.
9728102084 reads as week 28 of 1997.
Two sources agree InterNACHI water heater dating chart, InspectAPedia, Building Intelligence Center
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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The age you just looked up is the kind of fact that gets lost. A written record of serial numbers, install dates, repairs and who did the work saves the next owner, inspector or insurer from guessing.
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Galvanized, polybutylene, cast iron and the sewer line: what fails, what it costs, what insurance won't cover and how to decide.
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