subpanel for 2 mini splits

[PoorOwner]

2 Mini Split AC units are 9K BTU units, they are 240V, the min. circuit amplicity is 10 or 12A each and Max COP / Fuse is 15A each.

The AC units Rated input is around 800-1000W max so at 240V is only a few amps.

I was thinking instead of running 4 conductor THHN wires in conduit to the locations or maybe I could put in an outdoor rated subpanel.

so questions

1) I think the ones I saw is 60 amp and 4 space, however can you suggest (if) I can use a smaller feeding breaker like 30A on those load centers?

2) I have to run neutral even of I am not going to be using it?
2b) Do I need to run ground wire or can use EMT as the EGC in this?

 

[tyme2par4]

1: the 60 Amp rating is the max for the box. You can put whatever breakers in it that you want, as long as the feed is 60A or less.

2: I don't believe so, unless there's something in the code saying you do. Most minisplits are 3 wire feed.
-Note: I believe code does require a 120V outlet nearby, so if you don't already have one, you would run the neutral to use for that.

 

[wyliesdiesels]

Is there an outlet nearby for servicing

If not might as well get a slighly larger subpanel so you can have room for a single pole breaker for the outlet.

 

[PoorOwner]

Yes, there is an outlet if I open the door just plug in the garage outlet.
I think code needs it to be within 6' or so.. But I have never had any technician looked at me funny when I just hand them a 15amp extension cord.

Here is what I found in NEC regarding EMT as EGC. Regarding (B) though, my EMT isn't directly connected to the A/C, the whip can get a ground wire from grounded via EMT.

If you are thinking because I am being kind of cheap, it's only because I am planning to push 2 #10 THHN through EMT conduit, unfortunately 1/2" bender is all I use. The EMT is going to be 95% inside my garage except the 2 entry and exit LB penetrating the exterior wall.


358.60 Grounding. Grounding and bonding EMT shall be installed in accordance with 358.60(A) and (B).

(A) EMT shall be permitted as an equipment grounding conductor

(B) Where Air Conditioning or Refrigerating Equipment is installed outdoors, an equipment grounding conductor per 250.118(1) shall be provided within the raceway and shall be sized per 250.122.

 

[bigb56]

3 #10s STRANDED will fit easily into properly installed/assembled 1/2" EMT. Good luck if you try to run solids, especially through a 1/2" LB. The likelihood of conductor damage will be very high with solid #10 wire in a 1/2" LB.

You could also use a double disconnect although they cost more than a 2/4 3R panel.

The NEC requirement for a service receptacle is "within 25 feet and on the same level"

 

[wyliesdiesels]

Code forbids cords running through doors and windows

 

[Norcal]

Code forbids cords running through doors and windows

A receptacle in a garage like the OP's is not accessible for the required receptacle for servicing the HVAC equipment, which goes along with the post above.

 

[Toothaker]

A receptacle in a garage like the OP's is not accessible for the required receptacle for servicing the HVAC equipment, which goes along with the post above.

Interesting! I have a question. What is the purpose of the requirement? How is it different for a service tech to use an outdoor outlet as compared to an outlet which is nearby but indoor? Is it because the homeowner might not be home when the tech is servicing the unit and not available to unlock and open the door?

Note: I'm not arguing. And my house is compliant - there is a weather resistant, GFCI-protected outdoor outlet on each side of my outdoor HVAC equipment. Just curious.

Code forbids cords running through doors and windows

Wait, what? Is this code restriction for HVAC techs, or for everyone? That is, am I going against code when I vacuum out my vehicle in the driveway, using an outlet inside the garage? Again, not arguing, just want to know.

 

[PoorOwner]

Interesting! I have a question. What is the purpose of the requirement? How is it different for a service tech to use an outdoor outlet as compared to an outlet which is nearby but indoor? Is it because the homeowner might not be home when the tech is servicing the unit and not available to unlock and open the door?

Note: I'm not arguing. And my house is compliant - there is a weather resistant, GFCI-protected outdoor outlet on each side of my outdoor HVAC equipment. Just curious.



Wait, what? Is this code restriction for HVAC techs, or for everyone? That is, am I going against code when I vacuum out my vehicle in the driveway, using an outlet inside the garage? Again, not arguing, just want to know.

I have not owned any house that has an outlet near the central AC units on the outside. Some disconnects have a GFCI outlet on it for convenience to meet this code. But they are great for lights and power tools too

presumably it is for the tech to plug in vacuum pump and reclaiming machine etc.

 

[bigb56]

I have respect for the code but if a guy has a recep in the garage near the unit I would call it good. Were not talking rooftop and were not talking commercial here, and 90% of the service receps we install never get used.

 

[PoorOwner]

so with the 30A and 10AWG feeder seems good enough to handle those 2x 240V 15A breakers.

If I put in one more 15A 120V outdoor receptacle is that still ok? What neutral wire size would be needed?

 

[Norcal]

I have respect for the code but if a guy has a recep in the garage near the unit I would call it good. Were not talking rooftop and were not talking commercial here, and 90% of the service receps we install never get used.

It's not accessible if nobody is home, it needs to be on the exterior within 25'. Now that refrigerant recovery is required, they are needed before that & cordless tools being more common would have said not needed, but not being a service tech, never thought about a vacuum pump either.