A. O. Smith CAHP-80 vs Rheem PRO H80 T2 RH310UM
Two of the 240-volt heat pump water heaters in our best 240-volt heat pump water heaters comparison, lined up spec by spec. Every figure comes from the manufacturer pages linked below, and the scores use the same published formula as the full ranking.
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Best for: Official UEF 3.88, first-hour rating 95 gallons, 81 gallons certified storage, ENERGY STAR connected-capable
Check price at AmazonBest for: Official UEF 3.5, first-hour rating 87 gallons, 72 gallons certified storage, ENERGY STAR connected-capable
Check price at AmazonSpec-by-spec comparison
Green marks the better published figure. "Not listed" means the manufacturer doesn't publish it.
| Spec | A. O. Smith CAHP-80 | Rheem PRO H80 T2 RH310UM | Weight |
|---|---|---|---|
| Uniform energy factorOfficial ENERGY STAR uniform energy factor. Higher means more hot water delivered per unit of electricity. Missing values take the category minimum. | 3.88 | 3.5 | 36% |
| First-hour ratingOfficial ENERGY STAR first-hour rating in gallons. Missing values take the category minimum. | 95 gallons | 87 gallons | 28% |
| Certified storage volumeOfficial ENERGY STAR certified storage volume in gallons, which can differ from the marketed tank size. A larger tank is not automatically the right unit for a small household. Missing values take the category minimum. | 81 gallons | 72 gallons | 18% |
| Connected capableYes when the official ENERGY STAR record lists the model as connected-capable. Unstated counts as no. | Yes | Yes | 18% |
| Uniform energy factor (ENERGY STAR UEF) | 3.88 | 3.5 | info |
| First-hour rating (ENERGY STAR) | 95 gallons | 87 gallons | info |
| Certified storage volume (ENERGY STAR) | 81 gallons | 72 gallons | info |
| Annual energy use (ENERGY STAR) | 1279 kWh/year | 1303 kWh/year | info |
| Annual energy use per gallon (computed) | 15.8 kWh/year per gallon, computed as certified annual energy use ÷ certified storage volume | 18.1 kWh/year per gallon, computed as certified annual energy use ÷ certified storage volume | info |
| Connected capable (ENERGY STAR) | Yes | Yes | info |
| Heat pump type (ENERGY STAR) | 240 Volt Integrated HPWH | 240 Volt Integrated HPWH | info |
| Input voltage (ENERGY STAR) | 240 V | 240 V | info |
| Maximum current (ENERGY STAR) | 22.0 A | 21.0 A | info |
| Lower compressor cut-off temperature (ENERGY STAR) | 37.0 °F | 37.0 °F | info |
| Draw pattern (ENERGY STAR) | High-Usage | High-Usage | info |
| Recovery efficiency (ENERGY STAR) | 428% | 398% | info |
| Sound pressure level (ENERGY STAR) | Not listed | Not listed | info |
| Tank height (ENERGY STAR) | 69 in | 74.2 in | info |
| Tank diameter (ENERGY STAR) | 27 in | 24.3 in | info |
| Refrigerant (ENERGY STAR) | R-134a | R-134a | info |
| Certified model number | CAHP-80 2** | PRO H80 T2 RH310UM | info |
| Official brand name on the ENERGY STAR record | A. O. Smith | Rheem | info |
| HeatPick score | 7.9/10 | 6.0/10 | 100% |
Where each one comes out ahead
A. O. Smith CAHP-80
Better published figure on: Uniform energy factor, First-hour rating, Certified storage volume.
What we like
- High official first-hour rating (95 gallons)
- Largest official certified storage volume in this comparison (81 gallons)
- ENERGY STAR lists this model as connected-capable
Watch out for
- No additional scored gaps in the official record we used
Rheem PRO H80 T2 RH310UM
No scored spec where it is strictly ahead; its case rests on the strengths below.
What we like
- ENERGY STAR lists this model as connected-capable
Watch out for
- Official uniform energy factor of 3.5 is at the low end of this set
Verdict
Two official ~80-gallon-class 240-volt heat pump water heaters. The Rheem PRO H80 T2 RH310UM record lists 72 gallons of certified storage, an 87-gallon first-hour rating and a 3.50 UEF, and marks the model as connected-capable. The A. O. Smith CAHP-80 record lists 81 gallons of certified storage, a 95-gallon first-hour rating and a 3.88 UEF, and also marks the model as connected-capable.
- A. O. Smith CAHP-80: ENERGY STAR Product Finder: CAHP-80
- A. O. Smith CAHP-80: ENERGY STAR certified water heaters dataset
- Rheem PRO H80 T2 RH310UM: ENERGY STAR Product Finder: PRO H80 T2 RH310UM
- Rheem PRO H80 T2 RH310UM: ENERGY STAR certified water heaters dataset