TAKAGI TK-310U-E 2**
0.81 UEF DOE CCD · 2026-09-19Grade G: 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 checking the TAKAGI TK-310U-E 2**, it uses 209 therms of natural gas a year at the federal test's daily hot-water draw. That figure belongs to the high draw pattern, the standard daily hot-water usage DOE tests against. It sits 27 therms above the 182 therms median of 397 gas tankless models, ranking 323rd lowest in energy use.
Energy use per year
209 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 above the median of 182 therms for the 397 models registered in the same heater type and draw pattern; it ranks 323 of 397, lowest energy first.
Solid line: this model (209 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
- 0.81 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
- 4.8 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,698–$2,632 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 · 2026-09-24What 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 0.81 · Grade G Price it on your ZIP
This site computes the 209 therms figure; the registry does not publish it. The calculation 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 pattern. This model's registered UEF is 0.81. The registry data comes from the DOE Compliance Certification Database, retrieved 2026-09-19. The figure holds only at that federal test draw. A household that uses more or less hot water than the test assumes will see a different yearly figure than 209 therms. How far any single home departs from the test draw is not available in the data. The steps behind the figure are set out in how this site calculates annual energy and cost.
The high draw pattern stands for a larger household, or one where showers and laundry overlap. The registry lists this model's maximum flow rate in gallons per minute as 4.8. Whether that flow covers several fixtures running at once in a given home is not available in the data. On energy use, its rank of 323rd out of 397 places it in the highest quarter of its class. A reader who wants lower annual gas use at the same draw pattern would look at models below the class median. That group of models is listed by rank, not by name, on this page. Plumbers and sellers checking alternatives can find a same-class replacement by model number.
The text of this page states no running cost. The cost of 209 therms of natural gas a year depends on the reader's state average residential gas price. For that reason, the page computes it from the reader's ZIP rather than stating one figure for everyone. The 27 therms gap above the class median applies at any gas price. At the same rate and the same test draw, this model costs more to run than a median model in its class. What any one household actually pays is not known from the registry. The installed price range appears in its own block, with its source and date, as a modeled installed-cost range rather than a quote. To apply your own rate, use the cost calculator for your ZIP.
DOE CCD · 2026-09-19