Heat Pump Water Heater Circuit
A.O. Smith Voltex AL (Anti-Leak) Hybrid: Breaker & Wire Size
The circuit the A.O. Smith Voltex AL (Anti-Leak) Hybrid needs, transcribed from the manufacturer's own spec sheet, with the conductor and ground derived for the stated breaker.
Circuit Spec
| Voltage | 240V (240V dedicated) |
| Circuit | dedicated 240V circuit |
| Nameplate element wattage | 4,500 W |
| Nameplate amps | 18.75 A |
| Design amps at 125% (NEC 422.13) | 23.44 A |
| Manufacturer-required breaker | 30 A |
| Conductor for that breaker | #10 Cu |
| Equipment ground | #10 Cu |
| Load-sized circuit (code minimum) | 25A on #10 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: HPTS-50, HPTS-66, HPTS-80. Capacities: 50, 66, 80 gallons. The circuit spec above applies across the line as published by A.O. Smith; confirm against the rating plate on the specific unit.
A Dedicated Circuit, Wired Like a Standard Tank
Every 240V hybrid is a dedicated-circuit appliance; A.O. Smith states a dedicated 30A / 240V circuit for this line, on #10 copper with a #10 ground. It uses the same 4,500W backup element as a standard 4,500W / 240V electric resistance tank, which draws 18.75A (23.44A at the 125% continuous sizing, NEC 422.13) on the same 30A / #10 circuit (25A is the NEC code minimum), so it wires identically to the tank it typically replaces.
Source
Circuit data transcribed from the manufacturer: A.O. Smith Voltex AL (Anti-Leak) Hybrid specification, accessed 2026-07-11.
A.O. Smith's Voltex AL spec sheet states 240 VAC and requires a 30-amp breaker (4.5 kW element), so it takes the standard 30A / 240V circuit on 10 AWG copper. There is no 120V plug-in Voltex; the whole Voltex line is 208/240V.
Frequently Asked Questions
What size breaker does the A.O. Smith Voltex AL (Anti-Leak) Hybrid need?
A.O. Smith specifies a 30A breaker on a dedicated 240V circuit for this line (models HPTS-50, HPTS-66, HPTS-80). 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 30A breaker is #10 copper with a #10 copper equipment ground.
How many amps does the A.O. Smith Voltex AL (Anti-Leak) Hybrid draw?
With its 4,500W element on, it draws 18.75A at 240V (amps = watts / volts). A fixed storage water heater 120 gallons or less is a continuous load under NEC 422.13, so the circuit is sized at 125%: 23.44A design. In heat-pump mode the draw is far lower; the circuit is sized for the element.
Does the A.O. Smith Voltex AL (Anti-Leak) Hybrid need a dedicated circuit?
Yes. A.O. Smith states a dedicated 30A / 240V circuit for this line, and every 240V hybrid is a dedicated-circuit appliance. For comparison, a standard 4,500W resistance tank draws 18.75A at 240V, 23.44A at the 125% continuous sizing (NEC 422.13).
What wire size for the A.O. Smith Voltex AL (Anti-Leak) Hybrid?
#10 copper conductors for the manufacturer-required 30A breaker, with a #10 copper equipment ground sized to the breaker per NEC Table 250.122. Sized from the load alone: 4,500W / 240V = 18.75A, x1.25 continuous = 23.44A (NEC 422.13), which lands on a 25A code-minimum breaker with #10 copper. The manufacturer's marked maximum governs the installed breaker (NEC 422.11(E)).
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.
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 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.
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