A/C units

[Archieb1941]

Hey Guys
I’ve been trying to learn more about the correct wire size and breakers for A/C units. I found two examples yesterday. I think that if using UF wire I could use 12-2 and a double pole 20 for both?

 

[augie47]

Yes. (or a 25 amp breaker on the 2nd one)

 

[Dsg319]

Hey Guys
I’ve been trying to learn more about the correct wire size and breakers for A/C units. I found two examples yesterday. I think that if using UF wire I could use 12-2 and a double pole 20 for both?

Yep. I can only get the 2nd image to load (probably my phone). I don’t work with A/C much but from what I’ve learned about them it’s about as easy as it gets as they list min/max sizes of everything you need wire ampacity/OCPD. Only reason the conductors could vary from the listing from my point of view is ampacity adjustment and voltage drop that would effect wire size.

Might be pretty common to see larger than needed conductors though because they just match wire ampacity to the OCPD, but there’s motors involved and they have already done all the work for us.

 

[Buck Parrish]

25 on the second one. Otherwise you will get a nuisance trip occasionally.

 

[Archieb1941]

My second question would be if there was an existing 8-2 or 10-2 would I be able to use 25 or 20 amp fuses and then come out with a 12 tail to unit?

 

[Buck Parrish]

My second question would be if there was an existing 8-2 or 10-2 would I be able to use 25 or 20 amp fuses and then come out with a 12 tail to unit?

Yes, following the proper wiring methods, of course

 

[infinity]

My second question would be if there was an existing 8-2 or 10-2 would I be able to use 25 or 20 amp fuses and then come out with a 12 tail to unit?

Yes, also a 20 amp OCPD would work for either unit. If you used a raceway tail you could use #14 conductors.

 

[Archieb1941]

Yes, also a 20 amp OCPD would work for either unit. If you used a raceway tail you could use #14 conductors.

 

[Archieb1941]

Thank you very much for the help