DoesTheMath

GIANT HPACO-45 1**+AXST-50S 1**

3.52 UEF DOE CCD · 2026-09-19
B

Grade 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 this model, GIANT HPACO-45 1**+AXST-50S 1** uses 923 kWh of electricity a year at the medium draw pattern, the standard daily hot-water usage DOE tests against. That is 2,608 kWh below the class median of 3,531 kWh across 426 electric tank models. It ranks 70th lowest.

Energy use per year

923 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 70 of 426, lowest energy first.

This model: 923 kWh

Solid line: this model (923 kWh). Dashed line: the class median.

Min 773 kWh Median 3,531 kWh Max 3,569 kWh

DOE CCD · 2026-09-19

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What it costs to run where you live

Enter your ZIP to see what this unit costs to run a year on your own utility’s electricity rate.

What the registry files

UEF (Uniform Energy Factor) how much hot water you get for each unit of energy the heater uses
3.52 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
70 gal DOE CCD · 2026-09-19
Rated Storage Volume the tank size in gallons
46 gal DOE CCD · 2026-09-19
On the market since (ENERGY STAR) the date the manufacturer told ENERGY STAR the model went on sale
2026-02-13 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-A,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-744 (CO2), GWP 1 ENERGY STAR · 2026-09-19

What it costs to install

$3,030–$4,180 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) · 2026-04-01

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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 · 2026-09-24

Every water heater recall on file since 2015

Does 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
  • Ambient temperatureEnter your numbers1°F min
  • Physical footprintEnter your numbers18" ⌀
  • Electrical supplyEnter your numbers240V, 20.2A max
 ENERGY STAR · 2026-09-19

What these figures mean

The figure of 923 kWh is not read from the registry directly. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, which is 3.52 for this model, and from the DOE test's daily hot-water draw for the medium draw pattern. The source is DOE CCD, retrieved 2026-09-19. Against the class median of 3,531 kWh, this model sits 2,608 kWh lower. Its 70th lowest energy use of 426 places it in the lowest quarter of its class. The calculation method explains how the annual figure and the annual cost are derived.

The energy figure applies to households whose hot-water use matches the medium draw pattern, a typical household on a busy morning. The registry lists a rated volume of 46 gallons and a first hour rating, the gallons of hot water available in the first hour from a full tank, of 70 gallons. Those two values describe capacity, not energy use. A household whose daily use differs from the test draw should not read 923 kWh as its own consumption, because the figure is a standard-test value and not a measurement of any home. The water heater selector filters by fuel, space and size.

The running cost is not stated in this text because it depends on your own utility electricity tariff, which the registry does not contain. It follows from 923 kWh at your rate, and the cost calculator does that arithmetic from your ZIP. The gap of 2,608 kWh from the class median is an energy difference at the test draw, and its value in money depends on the same rate. The rank of 70th lowest covers only the 426 electric tank models registered at the medium draw pattern. To look at other models in the same class, find a same-class replacement by model number. Real-world consumption in any one home is unknown from this data.

DOE CCD · 2026-09-19

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

UEF 3.52 · Grade B Price it on your ZIP

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