Giant water heaters
5 basic models and 11 listed models.
Certified figures by basic model
| Basic model | Type | Storage volume (gal) | UEF | Flow at a 67°F rise (gal/min) | First-hour rating (gal) | Recovery efficiency | Model numbers |
|---|---|---|---|---|---|---|---|
| HPACO-45 1**+AXST-50LBTTP 1** | Heat pump | 48 | 3.55 | — | 72 | 428% | GTHPCO-45 1**+GTXST-50LBTTP 1* |
| HPACO-45 1**+AXST-50S 1** | Heat pump | 46 | 3.52 | — | 70 | 429% | GTHPCO-45 1**+GTXST-50S 1*, GTHPCO-45 1**+GTXST-50S 1**, GTHPCO-45 1**+GTXST-50STTP 1*, GTHPCO-45 1**+GTXST-50STTP 1**, GTHPCO-45 1**+GTXST-50T 1**, GTHPCO-45 1**+GTXST-50TTTP 1** |
| HPACO-45 1**+AXST-66 1** | Heat pump | 60 | 3.70 | — | 82 | 435% | GTHPCO-45 1**+GTXST-66 1**, GTHPCO-45 1**+GTXST-66TTP 1** |
| HPACO-45 1**+AXST-80 1** | Heat pump | 73 | 3.80 | — | 95 | 423% | GTHPCO-45 1**+GTXST-80 1**, GTHPCO-45 1**+GTXST-80TTP 1** |
| UTM-199X3-P 1*1 | Gas tankless | — | 0.95 | 6.0 | — | 96% | UTM-199X3-P 1*1 |
A range means the models under one basic model differ. A dash means the model has no such figure.
Per unit of energy, its heat into water, or UEF, reaches 3.80. That UEF is over 1 because heat pumps move heat from air into water. That UEF belongs to the HPACO-45 1**+AXST-80 1**, a heat pump model. This brand has an ENERGY STAR certified model number in each of its basic models.
Its basic models are heat pump and gas tankless water heaters. Its heat pump basic models come to 4 of its 5. The HPACO-45 1**+AXST-80 1** holds this brand's highest first-hour rating: 95 gallons. Those 95 gallons include water the tank heats while the hour runs. This brand's highest tankless flow belongs to the UTM-199X3-P 1*1. In the test, that flow warms by 67°F at 6.0 gallons per minute.
This brand's 11 model numbers rank it below 44 of the 117 brands on this site. Each of 7 other brands shares at least one basic model number with this brand. The brand that lists the most of them is A. O. Smith, at 4.
Basic models shared with other brands
| Brand | Shared basic models |
|---|---|
| A. O. Smith | 4 |
| American | 4 |
| GSW WATER HEATERS | 4 |
| John Wood | 4 |
| Lochinvar | 4 |
| RELIANCE WATER HEATERS | 4 |
| State | 4 |