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Reliance Water Heater Age Lookup

Reliance water heaters - built by State Industries in the A.O. Smith family - cover gas, electric, and power-vent models, each with a date code in the serial number. Enter yours to reveal the exact build date and how old your Reliance unit is. No account needed.

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Reliance Water Heater

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Finding Your Reliance Serial Number

Check these four spots on your Reliance water heater

Reliance water heater serial number locations

Common Locations

1
Side panel
near the bottom
2
Front panel
access / service door
3
Behind covers
removable access panels
4
Jacket label
upper side or top of tank

What to Look For

  • White or metallic manufacturer sticker
  • Labeled "Serial No." or "S/N"
  • Typically 8–12 characters long
  • Usually near the model number

Can't find it? Try removing access panels or checking behind the temperature dial.

Reliance Serial Number Examples

Reliance
C0512345670833A032628
Pre-2008: first letter = month (A=Jan ... J=Sep, skips I, M=Dec) + 2-digit year. 2008 and newer: YYWW (2-digit year + 2-digit week). Reliance decodes like State.

Don't worry if yours looks different - Reliance has multiple formats and our system can decode most variations.

About Reliance Water Heaters

Reliance water heaters are built by State Industries, part of A.O. Smith, and sold through home improvement retailers rather than plumbing wholesalers. The tank inside is a State tank. The badge marks the sales channel, not a different factory.

The line is ordinary residential gas and electric, mostly 30 to 50 gallons, glass lined with an anode rod. The detail worth reading is in the model number: the leading digits give the warranty tier, so a 6 50 model is the six year version of the same 50 gallon tank that a 10 50 model covers for ten. Those tiers can differ in insulation thickness and anode count, so they are not interchangeable units, and a Reliance lookup has to match the full model number rather than just the capacity.

Serials follow the State formats, most commonly a two digit year and the production week, so 1024123456 is week 24 of 2010, with older letter based codes on units built before mid 2004. When a Reliance part number comes up empty, the equivalent State model usually finds it.

Where to find the serial

Reliance water heaters are part of the A.O. Smith family and sold heavily at Lowe's, Menards, and through plumbing wholesalers. The rating plate is on the upper third of the tank, and the serial uses the standard A.O. Smith YYWW format.

What the serial actually looks like

1814C098765
Year 18 (2018), week 14, so early April 2018. Reliance follows the same YYWW serial format as A.O. Smith, State, and the other plants in the family.

Why the age is worth knowing

Reliance residential tanks carry 6, 9, or 12-year tank warranties depending on the line. Reliance is positioned as the value brand in the A.O. Smith family, and the 6-year units are the most common in service today. After year 8-10 these typically need replacement, often because the dip tube or anode rod has failed.

Quick answers for this brand

Is Reliance the same as A.O. Smith?

Reliance is one of the brands under the A.O. Smith Corporation umbrella, sharing manufacturing plants and the same component suppliers. The Reliance brand specifically targets value and big-box channels, while A.O. Smith branded units are sold through plumbing wholesalers. Tank construction and serial format are identical.

Where are Reliance water heaters made?

Reliance tanks come from the A.O. Smith plants in Ashland City, Tennessee and McBee, South Carolina, depending on the model. Both plants run the same lines that produce A.O. Smith, State, American, and several house brands. The serial encoding is consistent across all of them.

Why does my Reliance say 6-year warranty but the tank is leaking after 7?

The 6-year warranty is the manufacturer's coverage on the steel tank against corrosion failures. Once it expires, you're on your own. Replacement is almost always more economical than tank repair - the labor to drain, disconnect, and re-pipe is the same whether the tank is 1 day or 10 years old, so a fresh unit makes sense.