MRCOOL MEWH40S82S1
MRCOOL MEWH40S82S1 is in the DOE listing as of Oct 19, 2026.
- Electric storage water heater
- 1 listed model
ENERGY STAR certification does not cover this type of water heater.
Its figures are also listed under A. O. Smith ENS-40 1**.
Certified figures
- Storage volume
- 37gallons
- UEF
- 0.92Uniform energy factor
- First-hour rating
- 55gallonsHot water in the first hour
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| Model number | Storage volume (gal) | UEF | First-hour rating (gal) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|---|
| MTWH04540E | 37 | 0.92 | 55 | 98% | Medium |
UEF is the uniform energy factor. A dash means the model has no such figure.
It holds 37 gallons in the test, 3 gallons less than its 40-gallon sold size. Over one hour from a full tank, it gave 55 gallons in the test (its first-hour rating). Its tank holds 37 gallons, so reheating adds 18 gallons during the first hour. Among 477 electric storage models, 204 have a higher first-hour rating. Its first-hour rating matches the median for electric storage models.
In tests, 92% of the energy it uses ends up as hot water (UEF 0.92). In the test, daily hot water use was set to medium (its draw pattern). Of 297 electric storage models with the same draw pattern, 81 have a higher UEF. For its type and draw pattern, its UEF sits at the median. Of the energy spent to reheat water, 98% goes into it (its recovery efficiency).
Its test figures match those of 14 other basic models. Besides this brand, 7 brands list one or more of them. For the full group, see the A. O. Smith ENS-40 1** page.
Also listed as
They carry every figure in the table above.
- A. O. Smith ENS-40 1**
- American ENS-40 1**
- Lochinvar ENS-40 1**
- Midea D40-45FH
- Midea D40-45FJ
- Midea MEWH40S82S1
- Midea MEWH40T82S1
- MRCOOL MEWH40T82S1
- MRCOOL MTWH04540E
- MRCOOL MTWH04540ET
- RELIANCE WATER HEATERS ENS-40 1**
- State ENS-40 1**
2 more basic models carry these figures.
- Every MRCOOL basic model
- Every 40-gallon electric storage water heater
- Every electric storage water heater
Not covered
- Advertised figures. We have none on file for this model.