Lennox WHES040S45TD240S****
0.93 UEF DOE CCD · 2026-09-19Grade G: where this UEF sits among the 426 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
An electric tank, medium draw pattern (a typical three- or four-person household, about 55 gallons on a busy morning).
If you are checking this Lennox WHES040S45TD240S****, it uses 3,493 kWh of electricity a year at the medium draw pattern, the standard daily hot-water usage DOE tests against. That is 38 kWh below the 3,531 kWh median of the 426 electric tank models at that draw pattern, ranking 153rd lowest in energy use.
Energy use per year
3,493 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 below the median of 3,531 kWh for the 426 models registered in the same heater type and draw pattern; it ranks 153 of 426, lowest energy first.
Solid line: this model (3,493 kWh). Dashed line: the class median.
Min 773 kWh Median 3,531 kWh Max 3,569 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
- 0.93 DOE CCD · 2026-09-19 Compared only with other models registered as an electric 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
- 54 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
$1,597–$2,019 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 Lennox model on file
What this brand files, by heater type.
UEF 0.93 · Grade G Price it on your ZIP
The 3,493 kWh figure is computed by this site, not by 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 0.93, taken from DOE CCD data retrieved 2026-09-19. The result holds only at that test draw. A household using more or less hot water will use a different amount of electricity. Within its class, the unit sits 38 kWh below the 3,531 kWh median. That places it in the second-lowest quarter of the 426 electric tank models for energy use. Annual energy at other draw patterns is not available for this model.
This model has a rated volume of 36 gallons. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 54 gallons. Its test figures fit a household whose daily use matches the medium draw pattern, which DOE sets for a typical household. Some households need more than 54 gallons in the first hour from a full tank. For them, the rating shows this unit may not cover that demand. How this unit performs at a higher draw is not available in the data here. To compare other electric tank models at the medium draw pattern, use the same-class replacement search by model number. To look across fuels and tank sizes, try the water heater selector by fuel, space and size.
The running cost is not stated in this text because it depends on your own utility's electricity tariff. The energy part of the yearly cost is the 3,493 kWh figure multiplied by the rate you pay per kWh, at the medium draw pattern. The page works this out from your ZIP in the running cost calculator for your own ZIP. The steps behind that result are set out in how the annual cost is calculated. At any single rate, this unit's energy charge is lower than a median model's by 38 kWh times that rate, at the test draw only. The installed price appears in its own block with its source and date. That block shows a modeled installed-cost range, not a quote.
DOE CCD · 2026-09-19