Rheem XG40T06EC36U1
0.58 UEF DOE CCD · 2026-09-19Grade G: where this UEF sits among the 288 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
A gas tank, medium draw pattern (a typical three- or four-person household, about 55 gallons on a busy morning).
If you are verifying the Rheem XG40T06EC36U1, a gas tank water heater, it uses 191 therms of natural gas a year. That figure applies to the medium draw pattern, the standard daily hot-water usage DOE tests against. It sits 6 therms above the 185 therms median of the 288 gas tank models tested at that pattern.
Energy use per year
191 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 185 therms for the 288 models registered in the same heater type and draw pattern; it ranks 231 of 288, lowest energy first.
Solid line: this model (191 therms). Dashed line: the class median.
Min 148 therms Median 185 therms Max 194 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
- 0.58 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tank at the medium draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- Medium DOE CCD · 2026-09-19
- First Hour Rating how many gallons of hot water the unit can deliver in one hour, starting from a full tank
- 68 gal DOE CCD · 2026-09-19
- Rated Storage Volume the tank size in gallons
- 38 gal DOE CCD · 2026-09-19
What it costs to install
$1,293–$1,862 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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Is a 40-gallon water heater enough?
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 tank water heaters
Gas-fired storage tanks, every size and draw pattern on file.
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Every Rheem model on file
What this brand files, by heater type.
UEF 0.58 · Grade G Price it on your ZIP
The 191 therms figure is computed by this site. The registry does not publish it. It combines the model's UEF, the ratio of hot water delivered to energy used, of 0.58 with the daily hot-water draw that the DOE test sets for the medium draw pattern. That pattern stands for a typical household with a busy morning. The UEF comes from the DOE Compliance Certification Database (CCD), retrieved 2026-09-19. If your household draws more hot water than the test assumes, actual gas use will be higher than 191 therms. If it draws less, use will be lower. This page does not know your household's actual draw, so that difference is unknown. The method behind the annual energy and cost figures sets out each step.
Within its class, the Rheem XG40T06EC36U1 ranks 231st for lowest energy use among 288 gas tank models at the medium draw pattern. The gap to the class median is the 6 therms a year stated above. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 68 gallons. The rated volume is 38 gallons. These figures fit a household whose peak hour stays within the medium draw pattern. A household that often needs more than 68 gallons in one hour falls outside what this rating covers. The registry records no data on how the unit performs above that level. To compare models in the same class, use the same-class replacement search by model number.
The text of this page states no running cost for the 191 therms a year. That cost depends on the average residential gas price in your state, and prices vary from state to state. The page works it out from your ZIP in its own block. The cost calculator for your own ZIP runs the same calculation. The 6 therms a year above the class median also has a cost that changes with your gas price. Only your rate can show how large that cost is. The installed price range appears in a separate block with its own source and date. It is a modeled installed-cost range, not a quote. None of these figures cover how long the unit lasts, because the registry does not record that.
DOE CCD · 2026-09-19