DoesTheMath

JOHN WOOD GCF-50 1**

0.69 UEF DOE CCD · 2026-09-19
F

Grade F: where this UEF sits among the 414 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set

A gas tank, high draw pattern (a larger household, or one where showers and laundry overlap).

You are checking the JOHN WOOD GCF-50 1**, a gas tank water heater. It uses 245 therms of natural gas a year at the high draw pattern, the standard daily hot-water usage DOE tests against. That is 15 therms below the 260 therms median for the 414 gas tank models registered at the same draw pattern.


Energy use per year

245 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 260 therms for the 414 models registered in the same heater type and draw pattern; it ranks 130 of 414, lowest energy first.

This model: 245 therms

Solid line: this model (245 therms). Dashed line: the class median.

Min 188 therms Median 260 therms Max 277 therms

DOE CCD · 2026-09-19

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What it costs to run where you live

Enter your ZIP to see what this unit costs to run a year at your state’s average natural gas price.


What the registry files

UEF (Uniform Energy Factor) how much hot water you get for each unit of energy the heater uses
0.69 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tank at the high draw pattern.
Draw Pattern the standard daily usage profile DOE tests the unit against
High 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
84 gal DOE CCD · 2026-09-19
Rated Storage Volume the tank size in gallons
48 gal DOE CCD · 2026-09-19

What it costs to install

$2,082–$3,883 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) · 2026-04-01

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Safety 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 · 2026-09-24

What these figures mean

The 245 therms figure is not a registry field. This site calculated it from the registry's UEF, the ratio of hot water delivered to energy used. It also used the DOE test's daily hot-water draw for the high draw pattern. For this model the UEF is 0.69, from DOE CCD data retrieved 2026-09-19. Among the 414 gas tank models at the high draw pattern, it ranks 130th lowest in energy use. That puts it in the second-lowest quarter of its class for energy use. Each step of the calculation is set out in the method behind the annual energy and cost figures. A plumber or seller can check these values against the registry entry for GCF-50 1**.

The high draw pattern represents a larger household, or one where showers and laundry overlap. This model's first hour rating, the gallons of hot water available in the first hour from a full tank, is 84 gallons. Its rated volume is 48 gallons. A home with lighter daily use does not match the test condition, so its yearly energy use will differ from 245 therms. The registry data does not show how large that difference would be. The rating also does not cover a home that needs more than 84 gallons in the first hour. To compare other units registered at the same draw pattern, use the same-class replacement search by model number.

The running cost is not given in this text. It depends on your state's average residential gas price, so the page calculates it from your ZIP. The 15 therms gap below the class median can only be priced at that same rate. The water heater cost calculator for your ZIP shows the yearly cost of 245 therms of natural gas. The installed price range has its own block on this page, with its source and date. That range is a modeled installed cost, not a quote. This model's energy use under draw patterns other than high is not available.

DOE CCD · 2026-09-19

How this compares

The closest models in the same class — same fuel, type and draw pattern.


Keep going

UEF 0.69 · Grade F Price it on your ZIP