Heat-pump details
Heat-pump water heater electrical ratings: volts, amps and kilowatts as listed
By Isabella ReedPublished October 27, 2026Data as of October 27, 2026
Every one of the 441 integrated 240-volt heat-pump model numbers lists a maximum current between 12 and 27 A, and 81% of them list 21, 22 or 24 A. The 68 plug-in 120-volt models sit far lower, from 4.5 to 15 A.
What the listing gives
For each heat-pump model the ENERGY STAR list carries three electrical fields: the supply voltage, the maximum current in amps and an input power in kilowatts. They come from the partner’s certification, not from the DOE efficiency test, and the listing does not say how each was measured. This page reports them as listed and compares them only between heat pumps.
By subtype
| Subtype | Model numbers | Voltage | Max current, A | Median current | Input, kW |
|---|---|---|---|---|---|
| 240 V integrated | 441 | 240 V (441) | 12–27 | 22 | 2.3–5.5 |
| 120 V plug-in | 68 | 120 V (68) | 4.5–15 | 12 | 0.9–1.3 |
| Split system | 100 | 240 V (90), 230 V (6), 120 V (4) | 6–20.2 | 20.2 | 0.6–4.5 |
The integrated 240-volt units cluster tightly. Besides the current figures above, the most common listed input powers are 4.5 kW on 289 model numbers, 5.5 kW on 83 model numbers and 2.3 kW on 35 model numbers. All 73 integrated 240-volt rating sets list a single current for every model number in the set.
Bigger tanks, same current
Among the 240-volt integrated units, the listed current barely moves with tank size: under 50 gal, a median of 21 A across 180 model numbers; 50 to 69 gal, a median of 22 A across 127 model numbers; 70 gal and up, a median of 22 A across 134 model numbers. The figure follows the heater’s design family more than its rated volume, which the partner breakdown makes plain.
By listing partner
The four partners with the most 240-volt integrated model numbers list: Rheem Sales Company (169 model numbers): two values from 12 to 21 A, most often 21; A.O. Smith (114 model numbers): 22 A on all; GD Midea (27 model numbers): 24 A on all; Vaughn Thermal (19 model numbers): 23 A on all. A partner usually keeps one current across a whole line, so two sizes of one line rarely differ here.
Plug-in units: current against output
The plug-in 120-volt units come in four current classes. The lowest class, 4.5 A, holds only the smallest tanks, up to 46 gal of rated volume. Higher classes reach the larger tanks and the higher first-hour ratings, as the table shows.
| Max current | Rating sets | Model numbers | Rated volume, gal | First-hour rating, gal |
|---|---|---|---|---|
| 4.5 A | 2 | 20 | 36–46 | 45–55 |
| 7.5 A | 4 | 4 | 40–80 | 46–94 |
| 12 A | 2 | 20 | 59–72 | 63–84 |
| 15 A | 4 | 24 | 46–82 | 51–93 |
The draw pattern follows the first-hour rating, so the larger plug-in units are tested at the high pattern and the smaller ones at the medium or low pattern. Their UEFs therefore compare only within a pattern (see draw patterns).
Split systems
Most of the 100 split-system model numbers list 240 V; the exceptions are Eco-Logical OMNI-50HP1-1A (120 V), SanCO2 GS5-45HPC HP + ECO-119GLBK (230 V), SanCO2 GS5-45HPC HP + ECO-43SSAQB (230 V) and SanCO2 GS5-45HPC HP + ECO-83SSAQB (230 V) and 6 more. Their listed currents run from 6 to 20.2 A, and the most common value is 20.2 A on 84 model numbers.
The extremes
The highest listed current is 27 A on Phnix KA06-80 (240 V integrated); the lowest is 4.5 A on Friedrich PROH40 T0 FD120-M (120 V plug-in).
Recovery efficiency
The same listings give a recovery efficiency for 599 heat-pump model numbers, from 233% to 499% with a median of 428%. Values above 100% are expected for a heat pump, which moves heat rather than making it. Listed values outside 150 to 700% were treated as entry errors and removed (see Test and data).
Connected-capable listings
The list also carries a yes-or-no field, “Connected Capable”, for an optional ENERGY STAR criterion. The listing records only whether the partner claims it, not which features a model offers. Of the heat-pump model numbers, 301 of 441 integrated 240-volt units carry the mark, 68 of 68 plug-in units and 87 of 100 split systems. No gas or solar model on the list is marked connected-capable.
What these figures are not
- They are not a circuit or breaker size. The circuit a heater needs is set by the manufacturer’s installation instructions and the local electrical code.
- They are not running costs. The rated annual electricity use in kWh, from the DOE test, is on each heat-pump page; this site never converts it into money.
- They do not show how often the backup element runs, which depends on use and conditions the listing does not cover.
The electrical figures of every model number appear in the model-number table of its model-line page.
Sources
- U.S. EPA, ENERGY STAR Certified Water Heaters (data.energystar.gov, dataset pbpq-swnu), certified models as of October 27, 2026.