Heat Pump Water Heater Circuit
Heat Pump Water Heater Amps Chart
Nameplate watts, amps, the manufacturer-required breaker, and the derived conductor and ground for every major heat pump water heater line, with a standard resistance tank as the baseline.
Amps, Breaker & Wire by Model Line
| Brand | Model line | Gallons | Circuit class | Nameplate watts | Nameplate amps | Breaker | Conductor | Ground |
|---|---|---|---|---|---|---|---|---|
| Baseline | Standard 4,500W 240V electric resistance tank | - | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| Rheem | ProTerra Plug-in Heat Pump (Dedicated Circuit) | 40, 50 | 120V plug-in | Not printed | - | 15A | #14 Cu | #14 Cu |
| Rheem | ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) | 40, 50, 65, 80 | 120V plug-in | Not printed | 3.67 A (avg) | 15A | #14 Cu | #14 Cu |
| GE Profile | GeoSpring 120V Plug-in (FlexCapacity) | 40, 50 | 120V plug-in | Not printed | - | 15A | #14 Cu | #14 Cu |
| Rheem | Performance Platinum ProTerra Hybrid (30A) | 40, 50, 65, 80 | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| Rheem | Performance Platinum ProTerra Hybrid (Low-Amp, 15A) | 40, 50, 65, 80 | 240V dedicated | 2,250 W | 9.38 A | 15A | #14 Cu | #14 Cu |
| A.O. Smith | Voltex AL (Anti-Leak) Hybrid | 50, 66, 80 | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| A.O. Smith | Voltex Hybrid (HPTU, prior generation) | 50, 66, 80 | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| State | ProLine XE Voltex Hybrid | 50, 66, 80 | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| Bradford White | AeroTherm (RE Series) Hybrid | 50, 65, 80 | 240V dedicated | 4,500 W | 18.75 A | 30A | #10 Cu | #10 Cu |
| GE Profile | GeoSpring 240V (FlexCapacity) | 50 | 240V dedicated | Not printed | - | 30A | #10 Cu | #10 Cu |
Amps = watts / volts; a fixed storage water heater 120 gal or less is a continuous load (NEC 422.13), so the circuit is sized at 125%. The manufacturer nameplate governs the breaker (NEC 422.11(E)). “Not printed” means the manufacturer's sheet does not publish a wattage; those rows carry only the stated breaker and the conductor and ground derived from it, never an estimate. The (avg) figure is a manufacturer-stated average draw, not a nameplate maximum.
Frequently Asked Questions
What size breaker for a heat pump water heater?
The chart above lists the manufacturer-stated breaker per line. A mainstream 240V hybrid takes a 30A / 240V dedicated circuit on #10 copper, the same circuit as a standard 4,500W resistance tank (18.75A at 240V, 23.44A at the 125% continuous sizing, NEC 422.13). The 120V plug-in class takes a 15A / 120V circuit. Under NEC 422.11(E) the breaker must not exceed the rating marked on the appliance.
Why do some rows say the wattage is not printed?
Because the manufacturer's spec sheet does not print an element wattage for that line (GE does not publish one numerically, and the Rheem 120V dedicated plug-in has no resistance element). We never estimate a missing electrical value; those rows carry only the manufacturer-stated breaker and the conductor and ground derived from it. The rating plate on the unit lists the exact draw.
How is the amps column computed?
Amps = watts / volts, from the manufacturer-printed wattage. A fixed storage water heater 120 gallons or less is a continuous load (NEC 422.13), so the branch circuit and breaker are sized at 125% of that figure; the design-amps column shows the result. Where a line prints an average draw instead of a nameplate wattage (the shared-circuit HydroBoost model, about 3.67A), the chart marks it as an average.
Can any of these share a circuit?
Only 120V plug-in models the manufacturer lists for shared-circuit use. NEC 210.23(B)(2) limits fastened-in-place equipment to 50% of a 15A or 20A multi-outlet circuit; reduced by the 125% continuous factor that is 6A on a 15A circuit, 8A on a 20A circuit. Every 240V line on this chart requires a dedicated circuit.
Go Deeper
Heat Pump Water Heater Circuit Hub
Every model line with its breaker, wire, and shared-vs-dedicated verdict.
120V vs 240V
The two product classes side by side: circuit, wiring, and recovery.
Wire Size Calculator
The correct conductor per NEC 310.16 with derating and the 110.14(C) terminal cap.
Watts to Amps
Convert any nameplate wattage to amps at 120V or 240V.
What Size Breaker Do I Need
Breaker sizes for common loads, worked from the nameplate out.