Takagi T-KJr2-IN-NG
Amazon customer rating as of
Tankless Geek editorial score: 4.2/5
The Takagi T-KJr2-IN-NG is the smallest, most affordable unit in Takagi's lineup — a compact 140,000 BTU/h non-condensing indoor gas tankless rated up to 6.6 GPM with a 0.81 UEF. It's built around a commercial-grade copper heat exchanger for good heat transfer and corrosion resistance, includes freeze protection, an overheat cutoff, inlet/outlet thermistors, and a flame sensor, and direct-vents through a 4-inch stainless pipe out a side wall or the roof. Takagi positions it for light residential use — a small apartment or home — and radiant-heating applications, where it can typically run a shower and a sink at once.
Realistically it's a one-to-two-fixture heater: it delivers its 6.6 GPM only at a small rise, about 3.9 GPM at a 60 °F rise, and closer to 3.2 GPM in deep winter. As a non-condensing unit it's inexpensive and simple, with no condensate drain, but less efficient than a condensing model. Its ~4.3-star rating reflects solid satisfaction with reliability and value. The important caveat, shared across the brand: Takagi was discontinued as of December 31, 2025 — units still ship from stock, warranties (10-year heat exchanger) are honored, and parts remain for now, but long-term support will wind down. For a small home wanting dependable, budget-friendly gas hot water today, it's a proven pick with that future caveat in mind.
Key Features
Best Use Cases
Our Verdict
Takagi's smallest and cheapest tankless — a dependable one-to-two-fixture gas unit for a small home, apartment, or radiant loop. Non-condensing and modest, but proven and well-protected. The catch is the brand's end-of-2025 discontinuation: fine on remaining stock with warranties honored, but factor in tapering long-term parts support.
Technical Specifications
| Input | Up to 140,000 BTU/h (natural gas) |
|---|---|
| Max flow | Up to 6.6 GPM (≈3.9 GPM at 60 °F rise) |
| Efficiency | 0.81 UEF, non-condensing |
| Heat exchanger | Commercial-grade copper |
| Venting | 4" stainless, direct vent (sidewall or roof) |
| Warranty | 10-yr HX / 5-yr parts |
Specifications verified against the linked source documents. See Sources below.
How much hot water you'll actually get
Usable flow drops as incoming water gets colder. Figures are calculated from rated output (140,000 BTU × 0.81 UEF) and labeled as such — not bench-tested by us.
| Temperature rise | Typical scenario | Usable flow |
|---|---|---|
| 35 °F | Warm climate (75 °F in → 110 °F) | 6.5 GPM |
| 45 °F | Mild climate (65 °F in → 110 °F) | 5 GPM |
| 60 °F | Cool climate (50 °F in → 110 °F) | 3.8 GPM |
| 70 °F | Cold climate (40 °F in → 110 °F) | 3.2 GPM |
Usable flow at a 110 °F target: BTU × UEF ÷ (ΔF × 500), capped at the 6.6 GPM maximum (non-condensing, 0.81 UEF). Matches Takagi's ≈3.9 GPM at a 60 °F rise.
Pros
Cons
Buy it if…
- Small homes and apartments needing 1–2 fixtures
- Radiant-heating and light-residential applications
- Budget buyers wanting a proven copper-heat-exchanger unit
- Warm/mild climates where 6.6 GPM at a small rise suffices
Skip it if…
- Whole-home use with several simultaneous fixtures
- Cold climates needing high winter flow (drops to ~3.2 GPM)
- Buyers who need assured long-term factory parts support
Installation Requirements
Professional vs DIY
Gas and stainless venting make a licensed installer the safe route.
Takagi as a brand is being discontinued (Dec 31, 2025) — verify long-term parts and warranty support first.
Gas and electrical work should be done by a licensed professional, and most installs require a permit and must meet local building codes — DIY work can void the manufacturer warranty. Always confirm the unit's own manual for exact clearances, venting, and sizing.
What owners report
Themes summarized from retailer customer feedback (4.3/5 Amazon customer rating, 156 ratings, as of 2026-08-23). These are owner opinions, not our own bench testing.
Owners value its dependable operation and the commercial-grade copper heat exchanger in a compact, easy-to-place unit.
Reviewers are clear it suits one to two fixtures — a shower and a sink — rather than whole-home demand.
As Takagi's entry model, it's frequently praised for delivering the brand's reliability at a budget price.
Takagi's end-of-2025 discontinuation means warranties are honored and parts remain for now, but long-term support will taper.
Takagi T-KJr2-IN-NG FAQ
How many fixtures can the T-KJr2 run?+
Realistically one to two — typically a shower and a sink together. It's Takagi's smallest unit, best for light residential and radiant use, not whole-home demand.
Is Takagi still supported?+
The brand was discontinued as of December 31, 2025. Units still ship from stock, the 10-year heat-exchanger warranty is honored, and parts remain available while supplies last — but plan for support to wind down.
Is it condensing?+
No — it's non-condensing at 0.81 UEF. Simpler and cheaper with no condensate drain, but less efficient than a condensing unit and it needs 4-inch stainless venting.
Can it be used for radiant heat?+
Yes — Takagi lists it as suitable for radiant-heating applications as well as light residential domestic hot water.
Product sources
Specifications verified 2026-08-23. Manufacturer documents are treated as the primary source for model specifications. Retailer pages are used only for customer ratings and owner-feedback themes.
- Takagi T-KJr2-IN-NG — SupplyHouse specs (accessed 2026-08-23)
- T-KJr2-IN-NG — eComfort (0.81 UEF, 3.9 GPM @ 60°F) (accessed 2026-08-23)
- Takagi warranty & brand support (accessed 2026-08-23)
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