What is the best way to wire the Mini Split?

[dnwong]

I need to get a A/C disconnect connected next to my mini-split for my finished garage. I have a sub panel inside the garage and need to pull a wire to the a/c disconnect which will need to go through appx 3' inside a 2x6 insulated wall, come out through the exterior sheathing and siding and drop down another 6' (inside a PVC conduit) on the outside of the a poured concrete wall.

What type of wiring should I use?
What kind of box or transition would be the best to come out of siding? Do I use a siding block?

I do not want to run the conduit inside the walls since its already drywalled and I did not want to cut it all out.

 

[matt_i]

I'm having trouble viewing the picture, I can't zoom in, I get the basic idea but its still fuzzy.

Personally I would pull THHN/WN conductors in PVC conduit due to the "wet location", which is going to require cutting out a section of drywall for access. However you don't need too cut out the entire thing. You could potentially cut 2 access holes, or even one if your arms are long enough.

I would install a conduit "LB" direct to the siding, simply bed the horizontal pipe in silicone sealant and then a bead around the outside when its pushed home. This will also aid pulling wires to the AC disconnect.

Wire sized to amps drawn by the AC unit. I would use a #12 awg up to 20A or a #10awg up to 30A.

 

[Norcal]

In regards to wire size, what does the data plate say? It should say the minimum circuit amperes, & the maximum overcurrent device.

 

[dnwong]

Here is a better pic!

 

[wyliesdiesels]

Post a pic of nameplate or comment with make and model....bonus points if u have a link to the unit...

 

[dnwong]

https://www.highseer.com/high-seer-...ductless-mini-split-heat-pump-wys0018-17.html

 

[wyliesdiesels]

OK which model do u have?

The white paper lists MCA ranges from 15-25....

 

[dnwong]

I have the 18K model which requires 20amp circuit. My concern is the type of wire, not the size of wire to complete the circuit.

 

[dnwong]

I'm having trouble viewing the picture, I can't zoom in, I get the basic idea but its still fuzzy.

Personally I would pull THHN/WN conductors in PVC conduit due to the "wet location", which is going to require cutting out a section of drywall for access. However you don't need too cut out the entire thing. You could potentially cut 2 access holes, or even one if your arms are long enough.

I would install a conduit "LB" direct to the siding, simply bed the horizontal pipe in silicone sealant and then a bead around the outside when its pushed home. This will also aid pulling wires to the AC disconnect.

Wire sized to amps drawn by the AC unit. I would use a #12 awg up to 20A or a #10awg up to 30A.

So, that means that wire will not be in a conduit when it enters the wall and when it enters the subpanel or are u suggesting that I route the conduit inside the wall all the way up to the subpanel?

 

[wyliesdiesels]

I have the 18K model which requires 20amp circuit. My concern is the type of wire, not the size of wire to complete the circuit.

Actually, AC circuits are sized a little different. For AC circuits you wire to the MCA and breaker at the max... This is just the reason I asked..

U only need 15a rated wire on a 20a breaker.

As for the wire, u could use #14 and bring it into a disconnect, then use a liquid tight whip from the disconnect to the unit...

So, that means that wire will not be in a conduit when it enters the wall and when it enters the subpanel or are u suggesting that I route the conduit inside the wall all the way up to the subpanel?

If you use individual conductors, such as THWN, they need to be in conduit. So u would have to run conduit from the panel all the way to the disconnect, which means going through the wall.

Is this panel surface mounted or flush mounted?

 

[Norcal]

Actually, AC circuits are sized a little different. For AC circuits you wire to the MCA and breaker at the max... This is just the reason I asked..

U only need 15a rated wire on a 20a breaker.

As for the wire, u could use #14 and bring it into a disconnect, then use a liquid tight whip from the disconnect to the unit...



If you use individual conductors, such as THWN, they need to be in conduit. So u would have to run conduit from the panel all the way to the disconnect, which means going through the wall.

Is this panel surface mounted or flush mounted?

For the OP's project, 14 AWG THWN is rated 20A.

 

[dnwong]

Actually, AC circuits are sized a little different. For AC circuits you wire to the MCA and breaker at the max... This is just the reason I asked..

U only need 15a rated wire on a 20a breaker.

As for the wire, u could use #14 and bring it into a disconnect, then use a liquid tight whip from the disconnect to the unit...



If you use individual conductors, such as THWN, they need to be in conduit. So u would have to run conduit from the panel all the way to the disconnect, which means going through the wall.

Is this panel surface mounted or flush mounted?

The panel is flush mounted which require that I open the walls. I was looking for a way not to do that. Also, looks like it would be difficult to putt an elbow in the walll to turn outwards.

Could I put a junction box right outside the wall on the siding and run romex to the junction box and then THWN from junction box to the a/c disconnect? Use Wire Nuts in the Junction box?

 

[wyliesdiesels]

For the OP's project, 14 AWG THWN is rated 20A.

correct

I shouldve phrased that differently though i did say to use #14 below that...

 

[brewchief]

14-2 or 12-2 UF cable could go from panel to disconnect, use a couple of LBs and some 3/4" pvc conduit on the outside.