Lennox WHHP040T45MD240S****
3.55 UEF DOE CCD · 2026-09-19Grade B: 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 the Lennox WHHP040T45MD240S****, this site calculates its use at 915 kWh of electricity a year. That figure applies to the medium draw pattern, the standard daily hot-water usage DOE tests against. It is 2,616 kWh below the 3,531 kWh median for electric tank models tested at that pattern.
Energy use per year
915 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 60 of 426, lowest energy first.
Solid line: this model (915 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
- 3.55 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
- 65 gal DOE CCD · 2026-09-19
- Rated Storage Volume the tank size in gallons
- 37 gal DOE CCD · 2026-09-19
- On the market since (ENERGY STAR) the date the manufacturer told ENERGY STAR the model went on sale
- 2025-12-01 ENERGY STAR · 2026-09-19
- Connected / demand response (ENERGY STAR) whether the unit can take signals from your utility to shift when it heats, and by which standard (such as CTA-2045)
- Yes (CTA-2045-B) ENERGY STAR · 2026-09-19
- Refrigerant and GWP (ENERGY STAR) the refrigerant a heat pump unit uses and its global warming potential, a leak's climate effect relative to carbon dioxide (CO2 = 1)
- R-513A, GWP 630 ENERGY STAR · 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 · 2026-09-24Does it fit your space?
Enter your own numbers below — this compares them to what ENERGY STAR publishes for this model, it does not tell you what to buy.
- Compressor operating range (ENERGY STAR)
- the air temperatures around the unit in which its heat pump runs; outside this range the heat pump stops
- Dimensions (ENERGY STAR)
- the unit's filed height, width, depth or tank diameter, in inches
- Input voltage and maximum current (ENERGY STAR)
- the circuit voltage the unit is certified on and the most current it draws
What 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.
-
What size heat pump water heater do I need?
Answered from what models in this size actually file.
-
Water heaters
Every model on file with the Department of Energy, by heater type.
-
All heat pump water heaters
Electric tanks that file a UEF of 2.0 or more — the registry has no separate heat pump type, so this site draws the line there.
-
Every Lennox model on file
What this brand files, by heater type.
UEF 3.55 · Grade B Price it on your ZIP
The DOE CCD registry does not publish the 915 kWh figure. This site calculates it from the registry's UEF, the ratio of hot water delivered to energy used, and from the DOE test's daily hot-water draw for the medium draw pattern. The registry lists a UEF of 3.55 for this model. The registry data was retrieved on 2026-09-19. A household that draws more or less hot water than the test assumes will use a different amount of electricity. The registry also lists a first hour rating, the gallons of hot water available in the first hour from a full tank. For this model it is 65 gallons from a rated volume of 37 gallons. The method behind the annual energy and cost figures sets out each step of the calculation.
The registry lists 426 models as electric tanks tested at the medium draw pattern. Among them, this model ranks 60th lowest for energy use. Its 915 kWh a year compares with a class median of 3,531 kWh. The comparison holds only inside that class. Models tested at another draw pattern are not ranked against it here. The figure is most useful for checking a household whose daily hot-water use is close to the medium pattern. Where demand in the busiest hour exceeds the 65 gallon first hour rating, this rating does not show whether the unit will keep up. To check other units in the same class, use the same-class replacement search by model number. For a different fuel, space or size, the water heater selector by fuel, space and size filters the registry.
This page states no running cost for the Lennox WHHP040T45MD240S****. The cost of 915 kWh a year depends on the reader's own utility electricity tariff. The page does not have that tariff. The running cost calculator for your own ZIP applies your local rate to this model's annual energy figure. An installed price range is also not available for this model. The reason is that its ratings lie outside the range the cost database's model was fitted on. This site does not stretch that range past its fitted limits, so no installed price is shown. A plumber or seller quoting this unit needs a price source other than this page. The energy figure and the 60th rank among 426 models are the only comparisons this page can confirm.
DOE CCD · 2026-09-19