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.