Takagi T-KJr2-OS-NG Outdoor Compact Tankless Water Heater
Takagi T-KJr2-OS-NG Outdoor Compact Tankless Water Heater Review
The Takagi T-KJr2-OS-NG is an outdoor compact tankless water heater. "T-KJr2" identifies the Junior 2nd generation; "OS-NG" means outdoor sealed natural gas.
Specs: 140,000 BTU natural gas input, UEF 0.83 (non-condensing), 6.6 GPM at a 35°F rise, copper heat exchanger with stainless secondary, sealed direct-vent exterior mounting. 10-year warranty on heat exchanger.
The outdoor variant of the Junior 2 compact tankless is sized for 1-2 bath warm-climate homes with exterior wall mount location. Smaller gas line requirements than 199K BTU class — typically 1/2" gas line is sufficient at moderate distances.
About $1,100 unit, $2,300 installed. Right buyer: warm-climate small home with exterior mount location preferring compact unit versus full-size 199K BTU tankless.
- Outdoor mounting — eliminates indoor venting cost ($500–1,500 savings) and frees mechanical room space
- UEF 0.82 — above federal minimum EF 0.62; solid efficiency for a non-condensing gas unit
- 10-year warranty — solid above-average coverage for this class
- Requires dedicated 140K BTU gas supply line — undersized gas piping is the leading cause of flow-rate shortfalls