Takagi's residential warranty matches Rinnai Sensei and Navien NPE-A2 on the flagship condensing models (15-year heat exchanger). Non-condensing and commercial variants get shorter coverage, consistent with industry norms.
| Product | Heat Exchanger | Parts | Labor |
|---|---|---|---|
| T-H3 condensing | 15 years | 5 years | 1 year |
| T-D2 condensing | 15 years | 5 years | 1 year |
| T-K non-condensing | 10 years | 5 years | 1 year |
| T-KJr compact | 10 years | 5 years | 1 year |
| T-T commercial | 10 years | 5 years | 1 year |
| Commercial use (any model) | 5 years | 3 years | 1 year |
Warranty lookup
Need the model and serial number from the data plate. Then:
- Online: takagi.com / warranty section
- Phone: 1-877-882-5244 — Takagi customer service
- Through your installer: Takagi-trained installers submit claims via the AO Smith distributor channel
Registration
Register within 30 days of installation via takagi.com. Without registration, warranty defaults to manufacture date — potentially losing 6-12 months of coverage.
Filing a claim
- Note the error code if displayed
- Photograph the data plate
- Call 1-877-882-5244 or have your Takagi-trained installer call
- Takagi dispatches parts via AO Smith distribution to the installer
- Labor coverage applies only in year 1
What voids the warranty
- No annual descaling in hard water (over 11 grains per gallon)
- Non-licensed installer in jurisdictions requiring permits
- Improper venting (mixed manufacturers, wrong material, exceeded length)
- Wrong fuel (NG operated on LP or vice versa without conversion kit)
- Commercial use of residential model
Compared to other brands
Takagi's 15-year T-H3/T-D2 condensing warranty matches Rinnai Sensei, Navien NPE-A2, and Bosch Greentherm. Better than Noritz NRC (12-year) and Rheem RTGH (12-year). The AO Smith distribution back-end means parts availability is generally good across US markets.
Bottom line
Register inside 30 days, save installer invoice and descaling receipts, use Takagi-trained installers for warranty work. The 15-year T-H3/T-D2 warranty is industry-leading and worth defending with documented maintenance.