ARISTON ENS40LUB*
0.92 UEF DOE CCD · 2026-09-19Grade G: where this UEF sits among the 163 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
An electric tank, low draw pattern (a one- or two-person household).
If you are checking this unit's energy figure, the ARISTON ENS40LUB*, an electric tank, uses 2,439 kWh of electricity a year at the low draw pattern, the standard daily hot-water usage DOE tests against, which here means a one- or two-person household. That is 0 kWh from the class median of 2,439 kWh.
Energy use per year
2,439 kWh 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 electricity rate where you live.
That is equal to the median of 2,439 kWh for the 163 models registered in the same heater type and draw pattern; it ranks 19 of 163, lowest energy first.
Solid line: this model (2,439 kWh). Dashed line: the class median.
Min 724 kWh Median 2,439 kWh Max 2,550 kWh
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
- 0.92 DOE CCD · 2026-09-19 Compared only with other models registered as an electric tank at the low draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- Low 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
- 50 gal DOE CCD · 2026-09-19
- Rated Storage Volume the tank size in gallons
- 36 gal DOE CCD · 2026-09-19
What it costs to install
$1,591–$1,802 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 40-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 electric resistance tank water heaters
Electric tanks that file a UEF below 2.0 — heated by elements, not a heat pump.
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Every ARISTON model on file
What this brand files, by heater type.
UEF 0.92 · Grade G Price it on your ZIP
The figure of 2,439 kWh is computed by this site, not published by the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, of 0.92 with the daily hot-water draw the DOE test assigns to the low draw pattern. The source is DOE CCD, retrieved 2026-09-19. The value applies only to that test draw and to electricity as the fuel. Use in a home differs with the hot water actually drawn there, and this page has no data on that. The methodology page explains how the annual figure is calculated.
Among the 163 models registered as an electric tank at the low draw pattern, this model's rank is 19th lowest energy use of 163. That places it in the lowest quarter of its class. Its difference from the class median of 2,439 kWh is 0 kWh, so it sits equal to the median. The data here does not show how many models share this value. The figure suits a one- or two-person household, because that is the draw the test applied. The first hour rating, the gallons of hot water available in the first hour from a full tank, is 50 gallons, and the rated volume is 36 gallons. A household with a different draw is not covered by the 2,439 kWh figure. The water heater selector filters by fuel, space and size.
The running cost is not stated in the text, because it depends on the electricity tariff the reader pays. The 2,439 kWh figure is fixed by the test conditions, but the cost is that quantity applied to a local rate. The cost calculator uses the tariff for your own ZIP with this model's figure. The installed price range appears in its own block on this page, with its source and date, as a modeled installed-cost range and not a quote. For a replacement in the same class as the ENS40LUB*, the replacement finder works from a model number. This page reports only the registry and DOE figures, the energy value dated 2026-09-19.
DOE CCD · 2026-09-19