WireSizing
Wire gauge reference & calculator

Central Air Conditioner — Wire Size & Circuit Requirements

Central AC units typically draw 15-25 amps depending on size (2-5 ton). A 3-ton unit typically draws about 18-20 amps.

Wire Size
10 AWG
Breaker
30A double-pole
Voltage
240V
Typical Draw
20A

Wiring Specifications

Recommended wire10/2 with ground
Breaker30A double-pole
Voltage240V
Typical amperage20A
Circuit amperage30A
NEC referenceNEC 440
Max recommended distance50 feet (without voltage drop concerns)

Important Notes

AC units have high starting (LRA) currents that can be 3-5× running amps. The breaker and wire must handle the maximum circuit ampacity marked on the unit's nameplate. Check the MCA (Minimum Circuit Ampacity) and MOP (Maximum Overcurrent Protection) on the data plate.

Related

10 AWG specifications → Wire size for 30A circuits → Wire size calculator → All appliance guides →