wiring AC condensor

[CopperTone]

SO I have to wire an AC condenser tomorrow and wanted to be sure I was doing this correctly.

Name plate says " minimum circuit ampacity 27 amps minimun breaker size 40 amps"

So that means I am going to use a 2 pole 40 amp breaker with #12 wire to the disco and unit. #12 is good for 30 amp in the 90 degree c column in 310.16

That is right - right? just wanted to be sure.

thanks

 

[Dennis Alwon]

SO I have to wire an AC condenser tomorrow and wanted to be sure I was doing this correctly.

Name plate says " minimum circuit ampacity 27 amps minimun breaker size 40 amps"

So that means I am going to use a 2 pole 40 amp breaker with #12 wire to the disco and unit. #12 is good for 30 amp in the 90 degree c column in 310.16

That is right - right? just wanted to be sure.

thanks

You got the right idea but you are wrong with using the 90c column. Since your terminals are probably rated 75C you must limit the wire to 75C so #12 would not work. You need a #10

 

[augie47]

Dennis is correct, but I might add if you are using Romex, you would be restricted to the 60 deg column (334.80), still a #10 as Dennis states, but keep the 60 deg. in mind on Romex for future loads.

 

[LarryFine]

Name plate says " minimum circuit ampacity 27 amps minimun breaker size 40 amps"

It should say "minimum circuit ampacity" and "maximum over-current protection."

Size the wire for the former, and the breaker for the latter. #10 NM and 40a breaker.

 

[CopperTone]

it says exactly this on the nameplate
minimum circuit ampacity 27 amp
minimum breaker size 40amps
maximum breaker size 45 amps

I am using NM so 10/2 it is - thanks for the clarification guys

 

[LarryFine]

it says exactly this on the nameplate
minimum circuit ampacity 27 amp
minimum breaker size 40amps
maximum breaker size 45 amps

I am using NM so 10/2 it is - thanks for the clarification guys

Then you can use either a 40 or a 45a breaker, and the #10.

 

[elvis_931]

You cannot use romex. Most all condensors are located outside. You would have to run the romex in conduit to the condensor for physical protection. But code considers the inside of that conduit to be a wet location and romex is not rated for wet locations. You could run a UF cable in the conduit though.

 

[Dennis Alwon]

You cannot use romex. Most all condensors are located outside. You would have to run the romex in conduit to the condensor for physical protection. But code considers the inside of that conduit to be a wet location and romex is not rated for wet locations. You could run a UF cable in the conduit though.

Elvis. you can romex (nm cable). Every condensing unit I wired is done with nm cable simply because here is a disconnect we must hit first. From there we use carflex to the unit with individual conductors in it--- not nm cable.

So, if you do this then 60C must be used. In the case of the OP he may still use 10/2 nm to the disco---