Ductless Systems: Solid vs Stranded Wire

There are many different options and advantages to using a ductless mini-split system. From new construction installation to a retrofit application, these systems can be a solution for your heating and air-conditioning needs. There is no duct work needed for these systems allowing them to be installed almost anywhere without any major installation issues.

When installing these systems, it is highly recommended to run 14/3 stranded wire. Running stranded wire can prevent wire breakage and communication issues. Solid wire can break if installed incorrectly and cause communication and power issues with your system. Stranded wire is a lot more flexible and pliable with several soft strands of copper wire versus one hard copper wire.

Troubleshooting solid copper wire can be tricky. A solid copper wire that is partially broken can still read continuity when checking it with a volt meter. A lot of time, effort, and energy can be spent on a job troubleshooting power and communication issues due to the installation of solid wire. Making it a rule to run stranded copper wire on all ductless systems can save a lot of time and aggravation.

Most of the 14/3 AWG stranded copper wire can be purchased at Mingledorff’s and several other HVAC suppliers. 

38MARB

 Outdoor Unit Single Zone Ductless System

 Sizes 06 to 36

Power and Communication Wiring: The main power is supplied to the

outdoor unit. The field supplied 14/3 power/communication wiring, from

the outdoor unit to the indoor unit, consists of four (4) wires and provides

the power for the indoor unit. Two wires are high voltage AC power, one

is communication wiring and the other is a ground wire.

CABLE SIZE REMARKS

Connection Cable 14AWG 3 wire + Ground 1Φ 208/230 V

(Stranded wire is recommended)