STATE TK-510CX3 1**
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 STATE TK-510CX3 1**, here is its annual energy use. This gas tankless unit uses 209 therms of natural gas a year at the high draw pattern, the standard daily hot-water usage DOE tests against. That is 27 therms above its class median of 182 therms, ranking 323rd lowest energy use of 397.
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
- 5 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
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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 STATE model on file
What this brand files, by heater type.
UEF 0.81 · Grade G Price it on your ZIP
The 209 therms figure is calculated by this site. It is not taken from the registry. It combines the unit's UEF, the ratio of hot water delivered to energy used, which is 0.81. The second input is the DOE test's daily hot-water draw for the high draw pattern. The UEF comes from DOE CCD, retrieved 2026-09-19. The figure holds only at the federal test's daily draw. This data does not give energy use at other draw volumes. Each step is explained in how the annual energy and cost figures are calculated. This model is compared with the 397 models registered as gas tankless units at the high draw pattern. It ranks 323rd lowest energy use, which puts it in the highest quarter of its class for energy use.
The high draw pattern describes a larger household, or one where showers and laundry overlap. This model lists a maximum flow rate in gallons per minute of 5. The registry data does not say whether that rate covers a given home's fixtures running at the same time. For a household that matches the high draw pattern, the 27 therms gap to the class median applies as stated above. You can compare it with other models through a same-class replacement search by model number. For a smaller household, the 209 therms figure does not apply, because it belongs to the high draw pattern only. A figure for this model at another draw pattern is not available here. The selector by fuel, space and size lists other registered options.
This text does not give a running cost. It depends on your state's average residential natural gas price, so the page calculates it from your ZIP. The calculation uses this model's 209 therms a year at the high draw pattern, priced at your state's rate. The cost calculator for your own ZIP shows the result. This model uses 27 therms more gas a year than the class median of 182 therms. At any single gas rate, its running cost is therefore higher than the median model's at that same rate. The installed-price block on this page is a modeled range with its own source and date, not a quote. Energy use for other climates, rates or draw volumes is not available in this data.
DOE CCD · 2026-09-19