AC wiring question

[johno]

I'm installing a used Mini Split , ductless,AC unit in garage.

I know what the electrical demands are, ie amperage ,wire size, breakers etc.

What I don't know is

Does the wire go to the outside unit, and then run back to the inside unit, or are they two separate circuits, or something else I haven't thought of?

Thanks

 

[PoorOwner]

the main power just connect to the outside unit then there is a usually separate 4 wire cable that runs from the inside unit to outside unit (known as "communication cable" or "interconnect cable" ).
You don't need to be concerned what circuit or voltages for that 4 wire cable as long as you don't mix up the terminals. (they are assumed to be protected by the outdoor unit circuitry) But some jurisdiction will want you to put in a disconnect to cut off this communication cable because in all cases they carry some sort of voltage and they want to be sure the indoor unit can be shut off separately for servicing. In practice I don't think most people add that disconnect between the inside and outside unit.

 

[johno]

Thanks for the reply.

Is this interconnect cable carrying line voltage?
By which I mean 120V?

 

[brewchief]

Thanks for the reply.

Is this interconnect cable carrying line voltage?
By which I mean 120V?

Yes line voltage to run the indoor fan, probably 240v.

Every mini I have installed has called for a stranded wire instead of solid for the interconnect wire, it is very hard to find except from the companys that sell mini splits. Many wires that seem suitable are considered cord and can't be run through walls.

 

[PoorOwner]

As the interconnect cable, I have been using this with great success and passes all code.

http://www.homedepot.com/p/Southwir...e-58340803/205404476?keyword=mini+split+cable

for the inside I used regular MC cable connector as it does not need to be weatherproof. The outside connection I used arlington LTMC50.

Don't ever use romex as it is not rated to be exposed outside.

 

[johno]

Thanks again.

 

[Trey T]

They're the same circuit. The wall unit or ceiling cassette will require power and control wires to be fed from the condenser outside.

Mini-split wiring is pretty dummy-proof and well designed system.