DoesTheMath

GIANT HPACO-45 1**+AXST-66 1**

3.7 UEF DOE CCD · 2026-09-19
C

Grade C: where this UEF sits among the 194 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set

An electric tank, high draw pattern (a larger household, or one where showers and laundry overlap).

Checking the GIANT HPACO-45 1**+AXST-66 1**? It uses 1,341 kWh of electricity a year at the high draw pattern, the standard daily hot-water usage DOE tests against. That is 35 kWh above the 1,306 kWh class median, ranking 101st lowest of 194 electric tank models.

Energy use per year

1,341 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 above the median of 1,306 kWh for the 194 models registered in the same heater type and draw pattern; it ranks 101 of 194, lowest energy first.

This model: 1,341 kWh

Solid line: this model (1,341 kWh). Dashed line: the class median.

Min 1,002 kWh Median 1,306 kWh Max 5,334 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
3.7 DOE CCD · 2026-09-19 Compared only with other models registered as an electric tank at the high draw pattern.
Draw Pattern the standard daily usage profile DOE tests the unit against
High 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
82 gal DOE CCD · 2026-09-19
Rated Storage Volume the tank size in gallons
60 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

$3,505–$4,492 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 1,341 kWh a year is computed by this site, not published by the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, of 3.7 with the DOE test's daily hot-water draw for the high draw pattern. It describes electricity use at that draw only. Among the 194 models registered as an electric tank at the high draw pattern, the class median is 1,306 kWh. This model is 35 kWh above that median and ranks 101st lowest energy use of 194. The comparison holds only for models at the same draw pattern. The source is the DOE CCD, retrieved 2026-09-19.

The high draw pattern stands for a larger household, or one where showers and laundry overlap. The 1,341 kWh figure fits that use. A household that draws less hot water is not described by the test draw, so its own energy use would differ from 1,341 kWh. The registry lists a rated volume of 60 gallons and a first hour rating, the gallons of hot water available in the first hour from a full tank, of 82 gallons. The registry data cannot show whether 82 gallons covers your busiest hour at home, because that depends on your own peak use. To filter by fuel, space and size, use the water heater selector.

The running cost is not stated here because it depends on your own utility electricity tariff. The calculation multiplies the annual energy, 1,341 kWh, by your price per kWh. The cost calculator does this from your ZIP, and the page on how the annual cost is calculated sets out the method. The installed price range appears in its own block on the page, with its source and date, as a modeled range and not a quote. It is not repeated here. Actual use in a home is not available from the registry. Only the test-condition figure of 1,341 kWh at the high draw pattern is.

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 3.7 · Grade C Price it on your ZIP

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