Water heater warranties run 6 to 15 years depending on the unit and tier — but the on-paper warranty length is only part of the story. What's covered, what's NOT covered, how to register, and what voids the warranty matter just as much. This page is the brand-agnostic overview; see the brand-specific warranty hubs below for the precise terms.
Typical warranty coverage by type
| Type / tier | Tank / Heat Exchanger | Parts | Labor |
|---|---|---|---|
| Tank — entry tier (Rheem Performance, AO Smith Signature) | 6 years | 6 years | 1 year |
| Tank — mid tier (Rheem Performance Plus, AO Smith Signature Select) | 9 years | 9 years | 1 year |
| Tank — premium (Rheem Performance Platinum, AO Smith Signature Premier) | 10-12 years | 10-12 years | 1 year |
| Bradford White (all tiers) | 6 years (10-yr upgrade kit available) | 6 years | 1 year |
| Heat pump / hybrid | 6-10 years | 6-10 years | 1 year |
| Gas tankless | 12-15 years | 5 years | 1 year |
| Combi boiler | 10-15 years | 5 years | 1 year |
| Electric tankless | 5-10 years | 1-3 years | 1 year |
| Commercial install (any) | 3-5 years | 1-3 years | 1 year |
Three separate clocks
"Heat exchanger" or "tank" coverage is the longest — it covers the structural component. "Parts" covers internals (gas valve, control board, elements, thermostats). "Labor" is typically only the first year. After year 1, you pay labor even when the part is covered.
Example: a year-8 Rinnai Sensei heat exchanger fails (covered under 15-year warranty). Rinnai ships the part free to a Rinnai-trained installer; you pay the $400 labor.
Registration
Most water heater warranties require registration within 30 days of installation. Skipping registration usually means warranty starts from the manufacture date instead of install date — losing you potentially 6-12 months of coverage.
How to register:
- Manufacturer's website (rheem.com, hotwater.com for AO Smith, bradfordwhite.com, rinnai.us, navieninc.com)
- App-based for connected units (Rheem EcoNet, Rinnai ControlR, Navien NaviLink)
- Mail-in card from the installer packet (still works, slower)
You need: model number, serial number, install date, installer name and license, your contact info.
What voids the warranty
This is where most warranty claims are denied. Items that void coverage:
- No annual maintenance documented in hard-water regions — heat exchanger or tank failure with heavy scale = denied claim. Keep dated photos of maintenance
- Unpermitted installation — some states require permits for water heater work. Skipping the permit can void coverage
- Non-licensed installer in jurisdictions requiring licensure
- Improper venting — mixed manufacturers, undersized, exceeded length
- Wrong fuel — NG unit operated on LP without conversion kit, or vice versa
- Unauthorized modifications — bypassing safety devices, removing the anode rod entirely
- Non-OEM parts during warranty period
- DIY repair during warranty period — only manufacturer-authorized installers can perform warranty work
- Wrong application — residential unit installed commercially, or vice versa
Filing a warranty claim
- Document the failure — symptom, error code if displayed, photo of the data plate (model + serial), date
- Check warranty status via the manufacturer's online lookup or by calling support with the serial number
- Contact the installer FIRST if you used a manufacturer-authorized installer. They handle the claim through their distributor channel — faster than going through the manufacturer directly
- If installer is unavailable, call the manufacturer's customer service line
- Manufacturer authorizes a parts replacement (or full unit if structural failure)
- Parts ship to a manufacturer-authorized installer (NOT to the homeowner)
- Labor is your cost after year 1
Extended warranties — worth it?
Home warranty companies (American Home Shield, Choice Home Warranty, 2-10) sell extended water heater coverage at $30-80/year. Some installers offer extended labor warranties (3-5 years instead of 1) for $200-500 upfront.
Manufacturer's parts warranty is generally good enough for years 1-5. Extended labor coverage is worth considering if:
- You're keeping the unit 10+ years
- The unit is tankless or heat pump (more complex parts, higher labor)
- You don't have a regular plumber you trust
Home warranty company plans are typically NOT worth it — they have low coverage caps, restrict installer choice, and often deny claims.
Brand-specific warranty hubs
Related guides
- Maintenance — required to keep warranty valid
- Installation — permitting
- Replacement — when warranty is no longer worth defending
Bottom line
Register inside 30 days, keep maintenance documentation, use authorized installers for any work inside the warranty period, and the warranty will pay out as written. Most warranty denials are maintenance-related — the inspector sees scale and denies the claim. Don't skip the annual flush or descale.