RELIANCE WATER HEATERS T-H3M-DV-N 1**
0.9 UEF DOE CCD · 2026-09-19Grade D: where this UEF sits among the 80 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
A gas tankless unit, medium draw pattern (a typical three- or four-person household, about 55 gallons on a busy morning).
If you are checking its energy figure: RELIANCE WATER HEATERS T-H3M-DV-N 1** uses 123 therms of natural gas a year at the medium draw pattern. The draw pattern, the standard daily hot-water usage DOE tests against, is the condition for that figure. That is 12 therms below the class median of 135 therms among 80 models.
Energy use per year
123 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 135 therms for the 80 models registered in the same heater type and draw pattern; it ranks 10 of 80, lowest energy first.
Solid line: this model (123 therms). Dashed line: the class median.
Min 114 therms Median 135 therms Max 137 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
- 0.9 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tankless unit at the medium draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- Medium DOE CCD · 2026-09-19
- Maximum Gallons Per Minute how many gallons a minute it can heat while running continuously
- 3.3 gal/min DOE CCD · 2026-09-19
What it costs to install
$2,122–$3,129 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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Find a water heater that fits
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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 RELIANCE WATER HEATERS model on file
What this brand files, by heater type.
UEF 0.9 · Grade D Price it on your ZIP
The registry lists a UEF, the ratio of hot water delivered to energy used, of 0.9 for this unit. The registry does not list annual energy. This site computed 123 therms of natural gas from that UEF and the daily hot-water draw DOE uses for the medium draw pattern, which describes a typical household on a busy morning. The source is DOE CCD, retrieved 2026-09-19. Among the 80 models registered as a gas tankless unit at this draw pattern, this unit ranks 10th lowest for energy use. That places it in the lowest quarter of its class, with 12 therms less than the class median of 135 therms.
This figure suits a household whose hot-water use resembles the medium draw pattern, because 123 therms is tied to that daily draw and to no other. The unit's maximum flow rate in gallons per minute is 3.3. The data on this page does not state the incoming water temperature that flow depends on. Households with heavier or lighter daily use should not read 123 therms as their own consumption. Figures for other draw patterns are not available for this model here. To compare by fuel, space and size, use the water heater selector by fuel, space and size, or find a same-class replacement by model number.
Running cost depends on your own gas rate, so it is not written in this text. To estimate it, multiply 123 therms by your state's average residential gas price per therm. The cost calculator for your ZIP does this for you, and the page on how the annual cost is calculated sets out the method. The gap of 12 therms from the class median of 135 therms converts to a cost difference the same way, at whatever price applies to you. This page has no data on your household's actual consumption, only the test-based figure. The installed price range appears in its own block on this page, with its source and date.
DOE CCD · 2026-09-19