Takagi PCB — Failure Modes & Replacement

Takagi Water Heater Warranty

Takagi residential and commercial warranty terms — 15-year T-H3/T-D2 heat exchanger, 10-ye...

Takagi Tankless Troubleshooting

Symptom-based troubleshooting for Takagi T-H3, T-D2, T-K, T-KJr, and T-T commercial.

Takagi Error Codes

Every Takagi numeric error code, what it means, diagnostic sequence. Codes 111, 112, 121,...

Takagi Manuals & Spec Sheets

Where to find Takagi installation manuals, owner manuals, parts diagrams.

Takagi Customer Service

How to reach Takagi customer service for warranty, error code help, parts, installer locat...

Takagi Installation Guide

Install requirements for Takagi T-H3, T-D2, T-K, T-KJr, T-T commercial cascade.

Takagi Maintenance Schedule

Annual maintenance tasks for Takagi T-H3, T-D2, T-K, T-KJr, T-T.

Takagi Flush & Descale Guide

Step-by-step Takagi descaling — vinegar or commercial descaler, isolation valves, pump set...

Takagi Age Lookup

How to decode a Takagi serial number to find the manufacture date.

Takagi Recirculation Guide

Takagi units don't include built-in recirculation. How to add external Grundfos or Taco pu...

Takagi Temperature Setting

Default temperature, safe range, child-safety, dishwasher requirements on Takagi.

How to Reset a Takagi Tankless

Soft reset, hard reset on Takagi tankless and T-T commercial cascade. When to use each.

Takagi Code 111

Code 111 is "no ignition" on Takagi. Diagnostic sequence.

Takagi Code 112

Code 112 is flame failure mid-operation. Burner lit but flame dropped out.

Takagi Code 121

Code 121 is heat exchanger overheat. Almost always scaled heat exchanger.

Takagi Code 311

Code 311 is outlet thermistor (temperature sensor) fault.

Takagi Code 651

Code 651 is combustion fan motor or RPM sensor fault.

Takagi Code 991

Code 991 is exhaust restriction. Vent blocked by ice, debris, or birds.

Takagi Parts

Takagi parts directory: heat exchanger, flame rod, igniter, gas valve, PCB, flow sensor. D...

Takagi T-H3 Condensing

The T-H3 series is Takagi's flagship condensing tankless line. Models, sizing, comparisons...

Takagi T-D2 Condensing

The T-D2 line is Takagi's newer-generation condensing tankless, replacing the older T-M se...

Takagi T-K Non-Condensing

The T-K series is Takagi's non-condensing tankless line. Lower cost than condensing; requi...

Takagi T-KJr Compact

The T-KJr (junior) line is Takagi's most affordable tankless — compact 1-2 bath units.

Takagi T-T Commercial

The T-T commercial line — single units or cascade up to 6 units for light-to-medium commer...

Takagi Dealers

Takagi sells through the AO Smith distributor network, Lowe's, and Amazon.

Takagi Reviews

Field reviews of Takagi T-H3, T-D2, T-K, T-KJr, T-T.

Takagi vs Competitors

Takagi compared to Rinnai, Navien, Noritz, Rheem, Bosch.