Real world example of sizing help.

[Sparksy93]

I’m fairly new to sizing motors sizing HVAC equipment because I know it uses a little bit different rules than normal sizing circumstances.
So if someone could as concisely as possible show how they’d size both the wire size and overcurrent protection. As well as the fuseless disconnect, that would be helpful, this is a real world scenario which I find easier to understand rather than the vagueness of book problems.
The running amps for this outdoor minisplit unit is
14 amps compressor.
.37 fan motor.
It’s 240 volt. I would appreciate any and all tips on how to size it, I know me personally from layman electrical knowledge I would run a 12/2 circuit to it with a 20 amp double pole breaker. But I understand there may be some exceptions for HVAC equipment. Thanks!

 

[texie]

All A/C and refrigeration equipment with a hermetic compressor will have on the label a "minimum circuit ampacity" and you use that value to choose the conductors. It will also have a value for the maximum OCPD and you use that to pick your breaker size. And yes, it is OK to that the breaker listed on the label will often be much larger that the value otherwise permitted for the conductors.
You don't need to be concerned with all the other values on the data plate for installation purposes.

 

[Sparksy93]

I do not have access to the full nameplate yet as this is just some basic specs from HVAC guy that’s going to install it.
My circuit and breaker sound accurate then? Obviously 14 amps is below the 80% rule of a 20 amp breaker, and obviously 12ga wire in any chart will be equivalent and permissible to use a 20 amp breaker on it. Is there some trick to use smaller wire or am I correct with this analysis?

 

[Little Bill]

You need to have them give you the MCA (minimum circuit ampacity) that will give you the wire size. Also the MOCP or Max breaker or fuse.
You could end up with #12 wire on a 40A breaker but you need to know the nameplate specs. You can run larger wire that what the MCA says but to save on cost it is better to run what's listed on the plate.