ARISTON GSN30T2-3-*
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).
If you are checking the ARISTON GSN30T2-3-*, a gas tank water heater, it uses 185 therms of natural gas a year. That figure applies at the medium draw pattern, the standard daily hot-water usage DOE tests against. It equals the class median of 185 therms, a difference of 0 therms, among the 288 gas tank models at that draw pattern.
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
- 69 gal DOE CCD · 2026-09-19
- Rated Storage Volume the tank size in gallons
- 29 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 ARISTON 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 calculated by this site. The registry does not publish it. 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 medium draw pattern. For the GSN30T2-3-*, the UEF is 0.6. The rating comes from the DOE Compliance Certification Database (CCD), retrieved 2026-09-19. Among the 288 gas tank models at this draw pattern, the unit ranks 89th lowest in energy use. That puts it in the second-lowest quarter of its class, and at the median given above. The figure holds only at the test's daily draw. Energy use at any other daily volume is not available in this data.
The medium draw pattern stands for a typical household's daily use, including a busy morning. This model has a rated volume of 29 gallons. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 69 gallons. The 185 therms figure describes a home whose daily use is close to the medium test. It does not cover a home that needs more than 69 gallons within one hour. If you need a different fuel, space or size, use the water heater selector by fuel, space and size. To compare this unit with models in the same class, use the same-class replacement search by model number.
Running cost is not stated in this text because it depends on your state's average residential gas price. The page calculates it from your ZIP by applying that price to the 185 therms of natural gas at the medium draw pattern. You can run the same calculation with the water heater cost calculator for your ZIP. The steps are set out in how the annual running cost is calculated. An installed price range for the GSN30T2-3-* is not published. This model's ratings fall outside the range the cost database's model was fitted on. The site does not extend that model past its fitted range, so the installed price for this unit is unknown here.
DOE CCD · 2026-09-19