RELIANCE WATER HEATERS GCF-40 1**
0.64 UEF DOE CCD · 2026-09-19Grade E: 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).
The RELIANCE WATER HEATERS GCF-40 1** gas tank water heater uses 173 therms of natural gas a year. That figure applies at the medium draw pattern, the standard daily hot-water usage DOE tests against. If you are checking it, it sits 12 therms below its class median of 185 therms. It ranks 44th lowest of 288 models.
Energy use per year
173 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 185 therms for the 288 models registered in the same heater type and draw pattern; it ranks 44 of 288, lowest energy first.
Solid line: this model (173 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
- 0.64 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
- 70 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
$1,643–$2,763 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
-
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.
-
Find a water heater that fits
Three questions — fuel, hot water need, install space — narrow every model on file to the ones that fit.
-
What a water heater costs to run
Prices a unit's efficiency against your own utility's filed tariff for your ZIP code.
-
Is a 40-gallon water heater enough?
Answered from what models in this size actually file.
-
Water heaters
Every model on file with the Department of Energy, by heater type.
-
All gas tank water heaters
Gas-fired storage tanks, every size and draw pattern on file.
-
Every RELIANCE WATER HEATERS model on file
What this brand files, by heater type.
UEF 0.64 · Grade E Price it on your ZIP
This site computed the 173 therms figure; it is not a value printed in the registry. It uses this model's UEF, the ratio of hot water delivered to energy used, which is 0.64. That UEF is combined with the DOE test's daily hot-water draw for the medium draw pattern. The source is DOE's certification database (CCD), retrieved 2026-09-19. The medium pattern stands for a typical household with a busy morning peak. The figure is valid only at that daily draw. Energy use at heavier or lighter daily use is not available in this data. The steps behind the number are set out in how the annual cost is calculated.
The class used here is the 288 models registered as a gas tank at the medium draw pattern. Their median annual energy use is 185 therms. This model sits 12 therms below that median and ranks 44th lowest in energy use. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 70 gallons. Its rated volume is 38 gallons. These figures describe a home whose daily use matches the medium pattern. A home that needs more than 70 gallons in its first hour falls outside what this rating covers. To compare other models in the same class, use find a same-class replacement by model number.
No running cost is stated in this text. The cost of 173 therms of natural gas depends on your state's average residential gas price. For that reason, the page computes it from your ZIP instead of giving a single national figure. You can enter your own ZIP in the cost calculator on the reader's own ZIP. The installed price range appears in its own block with its source and date. It is a modeled installed-cost range, not a quote. If the medium draw pattern or a gas tank does not match the home, the selector by fuel, space and size lists models for other fuels, spaces and sizes.
DOE CCD · 2026-09-19