State's warranty structure positions the brand as the value tier vs AO Smith Signature. The 6-year ProLine tank warranty is shorter than AO Smith Signature Select (9-year) and significantly shorter than Signature Premier (12-year) — but the product itself is identical from AO Smith manufacturing.
| Product | Tank | Parts | Labor |
|---|---|---|---|
| ProLine atmospheric | 6 years | 6 years | 1 year |
| ProLine XE high-efficiency | 8 years | 8 years | 1 year |
| ProLine Power Vent | 6 years | 6 years | 1 year |
| Premier Hybrid heat pump | 10 years | 10 years | 1 year |
| Patriot Hybrid (legacy) | 10 years | 10 years | 1 year |
| Sandblaster commercial | 3 years | 3 years | 1 year |
| Commercial application (any residential model) | 3 years | 3 years | 1 year |
Warranty lookup
You need the model number and serial number from the data plate (top of unit or side). Then:
- Online: statewaterheaters.com / warranty section (operates under AO Smith corporate)
- Phone: 1-800-365-0024 — State customer service
- Through your installer: State-authorized installers can lookup and file claims via AO Smith distribution
Registration
Register within 30 days of installation via statewaterheaters.com. Without registration, warranty defaults to manufacture date — potentially losing 6-12 months coverage. Registration is faster than the AO Smith Signature equivalent because State uses a simpler tier structure.
Filing a claim
- Photograph the data plate (model + serial)
- Document the failure (leak photo, error code, symptom)
- Call 1-800-365-0024 or have your installer call
- State (via AO Smith) dispatches parts to a State-authorized installer
- Labor covered only in year 1
What voids the warranty
- No anode rod replacement in hard water — heaviest scale at claim time can deny tank failures
- Non-licensed installer in jurisdictions requiring permits
- Improper venting on Power Vent units
- Inadequate condensate drainage on Premier Hybrid heat pump installs
- Wrong fuel (NG operated on LP without conversion kit)
- Commercial use of residential-warranted model
State warranty vs AO Smith Signature
| State ProLine | AO Smith Signature Select | AO Smith Signature Premier | |
|---|---|---|---|
| Tank warranty | 6 years | 9 years | 12 years |
| Typical price (50-gal gas) | $749-949 | $849-1,049 | $949-1,249 |
For warranty-focused buyers, the AO Smith Signature tiers offer real value over State despite higher price. For pure value buyers, State delivers identical product at lower cost — accept the shorter warranty as the tradeoff.
Premier Hybrid 10-year warranty
The Premier Hybrid 10-year tank warranty matches AO Smith Voltex — there's no warranty penalty for choosing State over AO Smith Signature on the heat pump line. For heat pump buyers, State is the value play with no warranty downside.
Bottom line
Register inside 30 days, keep your installer invoice, replace the anode rod on schedule. For tank water heaters, State's 6-year ProLine warranty is the value tradeoff; for Premier Hybrid heat pump, the 10-year warranty is competitive with any major brand.