Heat Pump Water Heater Circuit
Rheem ProTerra Plug-in Heat Pump (Dedicated Circuit): Breaker & Wire Size
The circuit the Rheem ProTerra Plug-in Heat Pump (Dedicated 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 | dedicated 120V circuit |
| Nameplate element wattage | Not printed by the manufacturer |
| Nameplate amps | Not derived (no printed wattage) |
| 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: PROPH40 T0 RH120, PROPH50 T0 RH120. Capacities: 40, 50 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 combines two independent NEC requirements: 210.23(B)(2) caps equipment fastened in place at 50% of a 15A or 20A multi-outlet circuit, and because a storage water heater is a continuous load (NEC 422.13) the circuit must carry 125% of it (210.19(A)/210.20(A)), so the largest raw nameplate that fits is 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 (Dedicated Circuit) specification, accessed 2026-07-11.
Rheem's 120V plug-in DEDICATED model plugs into a standard 120V outlet (NEMA 5-15P) but the manufacturer requires that outlet to be on its OWN 15A circuit. It has no large resistance backup element, which is how a 120V unit works at all; recovery is slower than a 240V hybrid.
Frequently Asked Questions
What size breaker does the Rheem ProTerra Plug-in Heat Pump (Dedicated Circuit) need?
Rheem specifies a 15A breaker on a dedicated 120V circuit for this line (models PROPH40 T0 RH120, PROPH50 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 (Dedicated Circuit) draw?
Rheem does not print a wattage for this line, so no amp figure is derived here. The manufacturer-stated 15A breaker governs the circuit (NEC 422.11(E)); read the rating plate on the unit for its exact draw.
Can the Rheem ProTerra Plug-in Heat Pump (Dedicated Circuit) share a circuit?
Needs a dedicated circuit. The manufacturer requires a dedicated circuit; a general-purpose circuit tops out at 6 A (15 A x 50% / 1.25 = 6 A). The rule: NEC 210.23(B)(2) (fastened-in-place equipment 50% of the circuit) combined with the 422.13 continuous load carried at 125% per NEC 210.19(A)/210.20(A). 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 (Dedicated 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 with HydroBoost (Shared 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, 25A 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.
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