JOHN WOOD GPDX-50L 3**
0.73 UEF DOE CCD · 2026-09-19Grade E: 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).
If you are checking the JOHN WOOD GPDX-50L 3**, this gas tank water heater uses 232 therms of natural gas a year. That figure belongs to the high draw pattern, the standard daily hot-water usage DOE tests against. It sits 28 therms below the 260 therms median of the 414 gas tank models registered at that draw pattern.
Energy use per year
232 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 33 of 414, lowest energy first.
Solid line: this model (232 therms). Dashed line: the class median.
Min 188 therms Median 260 therms Max 277 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
- 0.73 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
- 118 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
$2,316–$4,484 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 50-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 JOHN WOOD model on file
What this brand files, by heater type.
UEF 0.73 · Grade E Price it on your ZIP
The 232 therms figure comes from this site's calculation. It is not a value printed in the registry. The calculation combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw for the high draw pattern. For this model the UEF is 0.73. The inputs come from the DOE Compliance Certification Database, retrieved 2026-09-19. At that test draw, the model ranks 33rd lowest in energy use of 414 gas tank models at the high draw pattern. That places it in the lowest quarter of its class. The figure holds only at the test draw. A household that uses more or less hot water will use a different amount of gas. The steps are set out on the page explaining how the annual cost is calculated.
The high draw pattern describes 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 118 gallons. Its rated volume is 48 gallons. A plumber or seller can compare these two values with the unit being removed. The 232 therms figure does not describe a smaller household using less hot water. Annual use at a lower daily draw is not available in the data. A home whose peak hour needs more than 118 gallons falls outside what this rating covers. To compare against other gas tank models at the high draw pattern, use the same-class replacement search by model number.
The running cost is not stated in this text. It depends on the average residential gas price in your state, so the page computes it from your ZIP. For the same reason, the 28 therms gap to the class median is not converted into a cost difference here. That difference exists only at a given gas price. You can run the figure in the cost calculator for your 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. The registry does not record how this model performs in a real home. That information is not available on this page.
DOE CCD · 2026-09-19