What Size Wire for Mini Split AC? — Complete Wiring Guide
A Mini Split AC requires 14 AWG minimum (check MCA) with a 15-20A (check MOP) on a 240V or 120V dedicated circuit. Here is the complete NEC-compliant wiring guide.
Mini Split AC Wiring Details
Ductless mini-split systems vary widely in size and electrical requirements. A 9,000 BTU (0.75 ton) unit may run on 120V and need only a dedicated 15A circuit, while a 24,000+ BTU (2 ton) unit needs 240V. Like central AC, use the nameplate MCA for wire sizing and MOP for breaker sizing. A typical 12,000 BTU (1 ton) mini-split has MCA of 9-12A at 240V, requiring 14 AWG wire minimum (most electricians use 12 AWG) and a 15-20A breaker.
NEC Code Reference
The wiring requirements for a Mini Split AC are governed by NEC Article 440. Always check the appliance nameplate for specific electrical requirements — the manufacturer's specifications take precedence over general guidelines. Your local AHJ (Authority Having Jurisdiction) may have additional requirements beyond the NEC.
Pro Tip
Mini-split installation requires a dedicated circuit per outdoor unit — you cannot share with other loads. Many 115V mini-splits can be plugged into a dedicated outlet rather than hardwired, making installation simpler. For multi-zone systems with one outdoor unit serving multiple indoor heads, only one circuit to the outdoor unit is needed.
Disclaimer: This guide is for reference only. All electrical work must be performed by or verified by a licensed electrician. Local codes may differ from NEC.