Heat Pump Water Heater Circuit
Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit): Breaker & Wire Size
The circuit the Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) needs, transcribed from the manufacturer's own spec sheet, with the conductor and ground derived for the stated breaker.
Circuit Spec
| Voltage | 120V (120V plug-in) |
| Circuit | shared 120V circuit (HydroBoost) |
| Nameplate element wattage | Not printed by the manufacturer |
| Nameplate amps | Not derived (no printed wattage) |
| Average draw (manufacturer-stated) | 440 W (3.67 A) |
| Manufacturer-required breaker | 15 A |
| Conductor for that breaker | #14 Cu |
| Equipment ground | #14 Cu |
The breaker is the manufacturer-stated value; the conductor and ground derive from that breaker. Under NEC 422.11(E) the overcurrent device must not exceed the rating marked on the appliance, so the nameplate on your unit always governs.
Models & Capacities
Representative models in this line: PROPH50 T0 RH120-M, PROPH65 T0 RH120, PROPH80 T0 RH120. Capacities: 40, 50, 65, 80 gallons. The circuit spec above applies across the line as published by Rheem; confirm against the rating plate on the specific unit.
Can It Share a Circuit?
The rule: NEC 210.23(B)(2) limits utilization equipment fastened in place to 50% of a 15A or 20A multi-outlet circuit, and the 125% continuous sizing for a storage water heater (NEC 422.13) reduces that to 40% of the rating, 6A on a 15A circuit. A listed unit may be cord-and-plug connected under NEC 422.16(A). This shared-circuit question applies only to the 120V plug-in class.
Source
Circuit data transcribed from the manufacturer: Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) specification, accessed 2026-07-11.
The HydroBoost SHARED-circuit model is listed by Rheem to run on a 120V circuit that already feeds other outlets. It draws only ~440W (about 3.7A) because it has no resistance element and a mixing valve extends the hot water, keeping it under the NEC shared-circuit ceiling. It still needs its own 15A branch where a dedicated circuit is available or locally required.
Frequently Asked Questions
What size breaker does the Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) need?
Rheem specifies a 15A breaker on a shared 120V circuit (HydroBoost) for this line (models PROPH50 T0 RH120-M, PROPH65 T0 RH120, PROPH80 T0 RH120). Under NEC 422.11(E) the overcurrent device must not exceed the rating marked on the appliance, so the nameplate governs. The conductor for a 15A breaker is #14 copper with a #14 copper equipment ground.
How many amps does the Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) draw?
Rheem prints an average draw of about 440W for this line, which is 3.67A at 120V (amps = watts / volts). It has no resistance element, which is what keeps the draw that low. The rating plate on your unit governs.
Can the Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit) share a circuit?
Can share a circuit. 3.67 A <= 6 A (15 A x 50% / 1.25 = 6 A); listed by the manufacturer for shared-circuit use. The rule: NEC 210.23(B)(2) (50% fastened-in-place) with 422.13 (125% continuous). A listed unit may be cord-and-plug connected under NEC 422.16(A).
What wire size for the Rheem ProTerra Plug-in Heat Pump with HydroBoost (Shared Circuit)?
#14 copper conductors for the manufacturer-required 15A breaker, with a #14 copper equipment ground sized to the breaker per NEC Table 250.122.
Compute Your Unit's Exact Amps
Read the watts off the rating plate and enter them below to get the exact draw at 120V or 240V. The rating plate governs over any typical value.
Other Heat Pump Water Heater Circuits
Rheem ProTerra Plug-in Heat Pump (Dedicated Circuit)
120V plug-in, 15A breaker on #14 Cu.
GE Profile GeoSpring 120V Plug-in (FlexCapacity)
120V plug-in, 15A breaker on #14 Cu.
Rheem Performance Platinum ProTerra Hybrid (30A)
240V dedicated, 30A breaker on #10 Cu.
Rheem Performance Platinum ProTerra Hybrid (Low-Amp, 15A)
240V dedicated, 15A breaker on #14 Cu.
A.O. Smith Voltex AL (Anti-Leak) Hybrid
240V dedicated, 30A breaker on #10 Cu.
A.O. Smith Voltex Hybrid (HPTU, prior generation)
240V dedicated, 30A breaker on #10 Cu.
State ProLine XE Voltex Hybrid
240V dedicated, 30A breaker on #10 Cu.
Bradford White AeroTherm (RE Series) Hybrid
240V dedicated, 30A breaker on #10 Cu.
GE Profile GeoSpring 240V (FlexCapacity)
240V dedicated, 30A breaker on #10 Cu.
Amps Chart (All Lines)
Every line on one table: watts, amps, breaker, conductor, ground.
120V vs 240V
The two product classes side by side: circuit, wiring, and recovery.
Related Tools
Wire Size Calculator
The correct conductor per NEC 310.16 with derating and the 110.14(C) terminal cap.
What Size Breaker Do I Need
Breaker sizes for common loads, worked from the nameplate out.
Load Calculator (NEC 220)
Can the panel handle it? NEC 220.82 sizing and the 220.87 existing-load check.
Watts to Amps
Convert any nameplate wattage to amps at 120V or 240V.
Appliance Amps
Typical running amps for common household appliances and the circuit each needs.
EV Charger Calculator
Wire, breaker, and panel capacity for a Level 2 charger per NEC Article 625.