Ruud PROG29-31U RH EC1
0.6 UEF DOE CCD · 2026-09-19Grade F: 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).
Checking the Ruud PROG29-31U RH EC1? This gas tank uses 185 therms of natural gas a year at the medium draw pattern, the standard daily hot-water usage DOE tests against. That equals the 185 therms median of the 288 gas tank models registered at the same draw pattern, a difference of 0 therms.
Energy use per year
185 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 equal to the median of 185 therms for the 288 models registered in the same heater type and draw pattern; it ranks 89 of 288, lowest energy first.
Solid line: this model (185 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
- 0.6 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
- 58 gal DOE CCD · 2026-09-19
- Rated Storage Volume the tank size in gallons
- 28 gal DOE CCD · 2026-09-19
What it costs to install
Not published: Installed cost range
This model's rated tank size lies outside the range NLR REMDB's cost model was fitted on, and the range is not stretched past it.
The annual energy figure on this page does not depend on this range and is unaffected.
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 · 2026-09-24What 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 30-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 Ruud model on file
What this brand files, by heater type.
UEF 0.6 · Grade F Price it on your ZIP
The 185 therms figure is computed by this site, not taken from the registry. It 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 medium draw pattern. For this model the UEF is 0.6, as listed in the DOE CCD registry retrieved on 2026-09-19. The annual figure holds only at that test draw. A household that uses more hot water than the test assumes will burn more gas. One that uses less will burn less, and this page has no figure for either case. The steps behind the number are set out in how the annual energy and cost are calculated.
Within its class, the model ranks 89th lowest energy use of 288 gas tank models at the medium draw pattern. That rank places it in the second-lowest quarter of the class, even though its energy use sits at the class median stated above. The data does not say how many models share the median figure. The medium draw pattern stands for a typical household on a busy morning. The model's first hour rating, the gallons of hot water available in the first hour from a full tank, is 58 gallons. It comes from a tank with a rated volume of 28 gallons. A household whose busiest hour needs more than 58 gallons falls outside that rating. For other sizes and fuels, use the water heater selector by fuel, space and size.
This page gives no running cost in the text. The cost of 185 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 naming one figure. The cost calculator for your own ZIP applies that rate to this model's annual energy. Its result carries the same condition as the energy figure: it holds at the medium draw pattern's test draw. An installed price range is not published for the PROG29-31U RH EC1. Its ratings lie outside the range the cost database's model was fitted on, and the range is not stretched past it. To compare this unit with others in its class, find a same-class replacement by model number.
DOE CCD · 2026-09-19