TAKAGI T-H3J-OS-N 1**
0.95 UEF DOE CCD · 2026-09-19Grade B: where this UEF sits among the 397 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
A gas tankless unit, high draw pattern (a larger household, or one where showers and laundry overlap).
If you are verifying the TAKAGI T-H3J-OS-N 1**, here is its annual energy figure. This gas tankless unit uses 178 therms of natural gas a year at the high draw pattern, the standard daily hot-water usage DOE tests against. That is 4 therms below the 182 therms median for its class of 397 models.
Energy use per year
178 therms a year
Computed by this site from the registry's UEF and the federal test's daily hot-water draw for this draw pattern. What it costs depends on the natural gas rate where you live.
That is below the median of 182 therms for the 397 models registered in the same heater type and draw pattern; it ranks 45 of 397, lowest energy first.
Solid line: this model (178 therms). Dashed line: the class median.
Min 173 therms Median 182 therms Max 209 therms
What it costs to run where you live
What the registry files
- UEF (Uniform Energy Factor) how much hot water you get for each unit of energy the heater uses
- 0.95 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tankless unit at the high draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- High DOE CCD · 2026-09-19
- Maximum Gallons Per Minute how many gallons a minute it can heat while running continuously
- 4.7 gal/min DOE CCD · 2026-09-19
- On the market since (ENERGY STAR) the date the manufacturer told ENERGY STAR the model went on sale
- 2012-08-01 ENERGY STAR · 2026-09-19
- Connected / demand response (ENERGY STAR) whether the unit can take signals from your utility to shift when it heats, and by which standard (such as CTA-2045)
- No ENERGY STAR · 2026-09-19
What it costs to install
$2,358–$3,405 installed
Not a quote — a modeled range of what installers have charged for this class of unit; your price will vary with labor rates, access, and local code requirements.
Escalation indexes: equipment (BLS PPI) latest available: August 2026; labor (BLS ECI) latest available: April 2026 to June 2026.
NLR REMDB (BLS PPI/ECI escalated) · 2026-04-01Safety record
No CPSC recall names this model.
Checked against the CPSC recall database. CPSC does not publish a model-level match for this product category, so this list is curated by hand from the manufacturer's recall filings.
CPSC · 2026-09-24Does it fit your space?
Enter your own numbers below — this compares them to what ENERGY STAR publishes for this model, it does not tell you what to buy.
- Dimensions (ENERGY STAR)
- the unit's filed height, width, depth or tank diameter, in inches
- Input voltage and maximum current (ENERGY STAR)
- the circuit voltage the unit is certified on and the most current it draws
- Vent type and size (ENERGY STAR)
- how a gas unit is vented, the vent's diameter and the height of its vent connector
What these figures mean
How this compares
The closest models in the same class — same fuel, type and draw pattern.
Keep going
How every figure on this page is calculated
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Find what replaces your water heater
Enter the model number off your old unit and see what is on file today, with the yearly cost difference.
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Find a water heater that fits
Three questions — fuel, hot water need, install space — narrow every model on file to the ones that fit.
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What a water heater costs to run
Prices a unit's efficiency against your own utility's filed tariff for your ZIP code.
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How to size a tankless water heater by GPM
Answered from what models in this size actually file.
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Water heaters
Every model on file with the Department of Energy, by heater type.
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All gas tankless water heaters
Gas-fired instantaneous units, sized by flow rate rather than tank gallons.
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Every TAKAGI model on file
What this brand files, by heater type.
UEF 0.95 · Grade B Price it on your ZIP
The 178 therms figure comes from this site, not the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw for the high draw pattern. For this model the UEF is 0.95, and the source is the DOE CCD, retrieved 2026-09-19. The figure holds only at that test draw. Energy use at any other household's draw is not available here. Among the 397 models registered as a gas tankless unit at the high draw pattern, this one ranks 45th lowest in energy use. That puts it in the lowest quarter of its class, 4 therms below the 182 therms median. The methodology page explains how the annual cost is calculated from these inputs.
The high draw pattern describes a larger household, or one where showers and laundry overlap. The 178 therms figure was modeled for a home like that. The registry lists a maximum flow rate in gallons per minute of 4.7 for this model. The temperature rise behind that rating is not available in this data. A home whose fixtures, running at the same time, call for more than 4.7 gallons per minute would exceed the listed rating. For a smaller home, the 178 therms figure does not describe its own use, as noted above. To compare other units, use the water heater selector by fuel, space and size. To check another unit in the same class, find a same-class replacement by model number.
The page does not state a running cost in the text. The cost of 178 therms of natural gas a year depends on your state's average residential gas price. For that reason the page computes it from your ZIP, and the cost calculator on your own ZIP shows the result. The same applies to the 4 therms gap below the class median. What that gap is worth depends on your rate and is not given here. The installed price appears in its own block, with its source and date. It is a modeled installed-cost range, not a quote, and this text does not restate its figures. At the high draw pattern, the 178 therms figure and the 45th rank of 397 are the values this text can verify.
DOE CCD · 2026-09-19